HARVARD UNIVERSITY LIBRARY OFTHE GRAY HERBARIUM Digitized by the Internet Archive in 2017 with funding from BHL-SIL-FEDLINK https://archive.org/details/arnoldia68arno The Magazine of the Arnold Arboretum amoiaia The Magazine of the Arnold Arboretum VOLUME 68 • NUMBER 1 • 2010 CONTENTS Arnoldia (ISSN 0004-2633; USPS 866-100) is published quarterly by the Arnold Arboretum of Harvard University. Periodicals postage paid at Boston, Massachusetts. Subscriptions are $20.00 per calendar year domestic, $25.00 foreign, payable in advance. Remittances may be made in U.S. dollars, by check drawn on a U.S. bank; by international money order; or by Visa, Mastercard, or American Express. Send orders, remittances, requests to purchase back issues, change-of-address notices, and all other subscription-related communica- tions to Circulation Manager, Arnoldia, Arnold Arboretum, 125 Arborway, Boston, MA 02130- 3500. Telephone 617.524.1718; fax 617.524.1418; e-mail arnoldia@arnarb.harvard.edu Arnold Arboretum members receive a subscrip- tion to Arnoldia as a membership benefit. To become a member or receive more information, please call Wendy Krauss at 617.384.5766 or email wendy_krauss@harvard.edu Postmaster: Send address changes to Arnoldia Circulation Manager The Arnold Arboretum 125 Arborway Boston, MA 02130-3500 Nancy Rose, Editor Andy Winther, Designer Editorial Committee Phyllis Andersen Peter Del Tredici Michael S. Dosmann Kanchi N. Gandhi Copyright © 2010. The President and Fellows of Harvard College 71)f ARNOLD ARBORETUM of HARVARD UNIVERSITY 2 Magnolias at the Scott Arboretum of Swarthmore College Andrew Bunting 13 Excerpts from Wild Urban Plants of the Northeast: A Field Guide Peter Del Tredici 26 Conserving the Dawn Redwood: The Ex Situ Collection at the Dawes Arboretum Greg Payton 34 Index to Arnoldia Volume 67 44 A New Plant Introduction from the Arnold Arboretum: Ilex glabra 'Peggy's Cove’ John H. Alexander III Front cover: 'Verbanica', a cultivar of saucer magnolia {Magnolia x soulangiana], was introduced in France in 1873. Photo by Nancy Rose. Inside front cover: Urban wildflower or wicked weed? A new field guide. Wild Urban Plants of the Northeast, doesn't judge, but will aid city dwellers in identify- ing the plants around them. Photo of hedge bindweed [Calystegia sepium) by Peter Del Tredici. Inside back cover: Plant propagator John H. Alexander 111 stands behind the original plant of Ilex glabra 'Peggy's Cove', a new inkberry cultivar. Photo by Oren McBee. Back cover: Dawn redwood {Metasequoia glyptostro- boides] has a storied history but continues to face conservation challenges. This unusual multi-trunked specimen is from a 1948 seed accession at the Arnold Arboretum. Photo by Michael Dosmann. SCOTT ARKORETUM Magnolias at the Scott Arboretum of Swarthmore College Andrew Bunting F rom the inception in 1929 of the Scott Arboretum of Swarthmore College, the mission has remained the same — to col- lect and display outstanding ornamental plants, specifically trees, shruhs, and vines. Since 1931, one of our most prominent collections of plants — and one that has stood the test of time — has been the magnolia collection. Early on, new magnolia accessions were received from notable nurseries, organizations, and individu- als including Bobbink and Atkins, Rutherford, New Jersey; Andorra Nursery, Chestnut Hill, I’art of the ii]a,t;nolia collection at the Scott Arborettim. Magnolias at the Scott Arboretum 3 The original type specimen of Magnolia virginiana var. australis 'Henry Hicks' still thrives at the Scott Arboretum (above). This cultivar bears fragrant, creamy white flowers and cold-hardy evergreen foliage (right). Pennsylvania; the Arnold Arboretum; Hicks Nursery, Long Island, New York; and Highland Park, Rochester, New York. At the time, John Wister, first director of the Scott Arboretum, was developing the campus based on an evolutionary or phyloge- netic tree, so all genera in a plant family were planted together, and hence all species in a fam- ily resided together. The magnolia collection housed both species and cultivars alike. In 1931, Wister began to get regular deliver- ies of many plants, especially magnolias, from Henry Hicks of Hicks Nursery on Long Island, New York. On May 8th, 1934, Hicks brought Wister a gift of plants which included 61 acces- sions representing 3,143 individual plants. These included seven seedlings of the sweetbay magnolia {Magnolia viginiana], a native species which was then known as Magnolia glauca. Of these original seven, only one survived. It was 4 ArnoUIia 6H/} Early History of the Scott Arboretum I n 1 929, lohn Caspar Wister was appointed the first director of the Arthur Hoyt Scott Horticultural Foundation (now the Scott Arhoretum). Wister graduated in 1909 with a degree from the School of Landscape Architecture at Harvard University, and supplemented this education with courses taken at the New Jersey Agricultural College. After graduation, Wister worked in landscape archi- tecture offices in both Philadelphia and New York. From his youth, John Wister was an avid plant collector. As a small boy he had exposure to estate gardening at different Wister properties located in and around Germantown, Philadelphia. At age 14 he grew 40 cultivars of chrysanthemums. After Wister started his professional career his interest in a myriad of plant groups and genera began to grow. Throughout his lifetime he was an avid collector of both herbaceous and tree peonies. Wister admired a photograph in a garden catalog that showed the peony collection of Arthur Hoyt Scott (for whom the Arboretum is named) and Edith Wilder Scott and in 1913 he met the Scotts at their home in Oak Lane, Philadelphia. On July 10, 1917, at the age of 30, Wister enlisted as a private in World War 1. Wister was sent to France. On his leave time during the war Wister toured the gardens of Europe. While in France he collected several cultivars of tree peonies and sent the plants hack to Mr. and Mrs. Scott. Wister was honorably discharged in 1919. Arthur Hoyt Scott was a graduate of the class of 1895 from Swarthmore College. His father, E. Irvin Scott, founded Scott Paper Company which was located in Chester, just south of Swarthmore, Pennsylvania. Like Wister, Scott developed a passion for ornamental horticulture as a young man. In 1920 he became president of the Scott Paper Company, but his spare time was primarily occupied by his love of plants. Scott served as an officer of the American Peony Society and the American Iris Society. As early as 1915 Scott was sending gifts of plants to his alma mater, Swarthmore College. His first gift was 100 lilacs of many different varieties. In 1919 the Scotts moved from Philadelphia to a 100-acre farm in Rose Valley near Swarthmore. As Wister later wrote "Here for the first time he had ample room. He at once began to plant great collections of flowering trees and shrubs like Japanese cherries, crahapples, dogwoods, lilacs, mockoranges and azaleas." When Arthur Hoyt Scott wanted to study peonies he had to travel to Cornell University and when he wanted to see lilacs he had to go to Highland Park in Rochester, New York. Scott dreamed of having an arboretum at Swarthmore College where local gardeners could go and see attractive displays of his favorite plants. Scott had the support of Samuel Palmer, the head of the Botany Depart- ment, and Swarthmore College. Palmer, in turn, contacted Robert Pyle who had graduated from Swarthmore in 1897 and was serving on Swarthmore's board of managers. Pyle was head of the Conard-Pyle Company, one of the country's largest purveyors of mail-order roses. Magnolias at the Scott Arboretum 5 John C. Wister (second from right) at the dedication of the Scott Arboretum’s rose garden in 1958. VVister was director of the Scott Arboretum from 1929 to 1969. Arthur Hoyt Scott died in 1927, at the age of 51. Two years later Edith Wilder Scott and Arthur Hoyt Scott's sister, Margaret Moon, and her husband, Owen Moon, approached Swarthmore's president with the idea of starting a campus arhoretum. They recommended that John Wister become its first director, and so indeed he did. The early 1930s were the heydays of the Scott Horticultural Foundation. With Wister at the helm, the plant collections grew very quickly. Huge collections of Paeonia, Iris, Rhododendron, Syringa, Philadelphus, Primus, Malus, Cotoneaster, Chrysanthemum, Narcissus and Magnolia were being accessioned and planted. In 1931 the Foundation accessioned 783 plants; in 1932 there were 1162 acces- sions, and in 1933, 1110 accessions. To put this in perspective the Scott Arbo- retum currently accessions about 300 plants per year. ARCl IIVES t )r 1 HL SCOTT ARHORETUM OF SWART! IMORE COLLEC'.E 6 Arnoldiii 6HI1 planted in a poorly drained section ot the Magnolia Collection, and over the years this sweethay magnolia thrived (unlike most mag- nolias, this species performs well in wet soils). It was observed that while most specimens of Magnolia viriginiana in the Swarthmore area are deciduous, this particular specimen was reliably evergreen. In 1967 this clone was offi- cially registered and named Magnolia virgin- iana var. australis 'Henry Hicks'. The original type specimen remains m great shape today in the old Magnolia Collection. A Stream of Magnolias In addition to Magnolia virginiana, several accessions of Oyama magnolia {Magnolia sieholdii, previously M. parviflora], a shrubby Asian magnolia noted for its white flowers with striking crimson stamens, were added to the collection from several different sources. Other early additions included the star magnolia {Magnolia stellata), anise magnolia {Magno- lia salicifolia), umbrella magnolia {Magnolia tripetala], Kohus magnolia {Magnolia kobus], southern magnolia {Magnolia grandiflora], cucLimbertree magnolia {Magnolia acuminata], and the saucer magnolia (M. x soulangiana, syn. Magnolia x soulangeana). Magnolia x soulangiana resulted from a cross between Magnolia denudata and Magnolia lili- iflora in 1820 by Etienne Soulange-Bodin, who was the first director of the Royal Institute of Horticulture near Paris. For many gardeners across the United States, saucer magnolia is the quintessential magnolia species. This large shrub to medium-sized tree produces masses of large, showy flowers that emerge before the foliage. The flowers, which are often fragrant, appear in white and shades of pink and purple. In the early 1930s the Scott Arboretum received two different hatches of Magnolia x soulangiana cultivars. In 1933, Arthur D. Slavin at Highland Park in Rochester, New York, sent 'Alexandrina', which has deep red-purple flow- ers and was introduced in Paris in 1831; 'Ama- hilis', an 1865 French introduction with white flowers; 'Alba', which is another white-flow- ered clone that was grown and named by Louis van Houtte of Belgium; 'Andre Leroy', which has dark pink to purple flowers and is a French The slightly nodding flowers of Magnolia sieholdii bloom in late spring or early summer. Early-spring-flowering Magnolia salicifolia has fragrant, 6-tepaled white flowers and a pyramidal growth habit. SCOTT ARBORETUM Magnolias at the Scott Arboretum 7 Magnolia x soulangiana 'Alexandrina' is noted for its dramatic red- purple flowers. A David Leach hybrid of M. acuminata x M. denudata, 'Ivory Chal- ice’ bears large, pale yellow to cream colored flowers. introduction from 1892; 'Brozzoni', which bears white flowers with pink veins and was named in honor of Camillo Brozzoni in Brescia, Italy in 1873; 'Lennei', which has tepals that are magenta on the outside and white on the inside,- 'Norbertii', a late- hlooming cultivar with red-purple flow- ers; and 'Verbanica', which has deep pink flowers and was named by Andre Leroy in France in 1873. In 1936, scions of all these clones were sent to Verkades Nursery in Wayne, New Jersey. The magnolias were propagated there, and duplicate plants were then sent back to the Scott Arboretum. Today, many of these original cultivars from Highland Park are found in our col- lections. Noted magnolia expert Philippe de Spoelberch from Arboretum Wespelaar, Haacht-Wespelaar, Belgium, commented that the Scott Arboretum's collection of Magnolia x soulangiana cultivars is impor- tant because they most likely represent clones which are true to name. De Spoel- berch said that many of the original culti- vars from France are much confused in the nursery industry and that many cultivar names have been mistakenly attributed to the wrong cultivar. Southern Belles and Little Girls In 1933, the Scott Arboretum received its first plant of the southern magnolia {Magnolia grandiflora] as a gift from Edith Wilder Scott. This large magnolia, native to the southeastern United States, is prized for its leathery evergreen foliage and large, fragrant, creamy white flowers. Several cultivars of this species were soon added to the collection; in 1939, 'Exoniensis' was received from Princeton Nursery, and in 1940 'Lanceolata' arrived from Hillier and Sons in Winchester, England. Both of these clonal names are synonymous with 'Exmouth', which is a fastigiate cultivar. It was not until 28 years later, in 1968, that any additional selections of the southern magnolia were added to the Arboretum's collections. 'Edith Bogue' was a selection that was made in 1961 for its ability to with- stand very cold temperatures with minimal sc >T' ARBORE 1;M S Arnoldia 68/1 leaf burn. Our plant came from Kingsville Nurs- ery in Kingsville, Maryland. Today, there are several specimens of 'Edith Bogue' growing on the campus of Swarthmore College, as well as 7 other M. grandiflora cultivars including both 'D. D. Blanchard' and 'Pocono' which also have been selected for greater cold hardiness. In 1968 the Scott Arboretum also received an important collection of magnolias from the United States National Arboretum. Commonly referred to as the Eight Little Girls, these magnolias were the result of hybridizing work conducted at the USNA by research geneticist Dr. Francis deVos and horticulturist William Kosar. In 1953, deVos began breeding working using Magnolici liliifloia 'Nigra' and Magnolia stellata 'Rosea'. 'Nigra' was used for its hardi- ness and late blooming, while 'Rosea' was used for its fragrance, prolific flowering, and mildew resistance. The results of this program resulted in the introduction of cultivars 'Ann', 'ludy', 'Randy', and 'Ricki'. In 1956, Kosar hybridized Magnolia stellata 'Rosea' and 'Waterlily' with Magnolia liliifloia 'Nigra' and 'Reflorescens', which resulted in the introduction of cultivars 'Betty', 'lane', 'Pinkie', and 'Susan'. Today at Magnolias at the Scott Arboretum 9 A specimen of the rare Florida native Magnolia macrophylla subsp. ashei growing at the Scott Arboretum. the Scott Arboretum 'Ann', 'Betty', and 'Susan' remain as beautiful mature specimens, while the others that we lost have been replaced with younger specimens. The "Little Girl" hybrids remain a group of magnolias that we continue to promote as relatively small (about 12 to 20 feet [3.5 to 6 meters] tall) magnolias for the home garden. In addition to Magnolia viiginiana and Mag- nolia grandiflora, the Scott Arboretum added several other magnolia species native to the United States. We received the umbrella mag- nolia {Magnolia tripetala) from the Hicks Nurs- ery in 1932 and Magnolia fraseri came from Arthur D. Slavin at Highland Park Nursery in 1933. Magnolia macrophylla, which is closely related to Magnolia fraseri, was acc]uired from Andorra Nursery near Philadelphia in 1939. The Scott Arboretum's first plant of Magnolia pyramidata (which is sometimes listed as Magnolia fraseri subsp. pyramidata) came to us via the Henry Foundation for Botanical Research in Gladwyne, Pennsylvania in 1971. This spe- cies is native to the coastal plains of Alabama, Georgia, Florida, Louisiana, Mississippi, South Carolina, and Texas, while Magnolia fraseri is only found in the mountains. It wasn't until 1991 that we added the last of the North Ameri- can native magnolias, a single plant of Magno- lia macrophylla subsp. ashei. Ashe's magnolia is very rare in the wild and only occurs in a small portion of the Florida panhandle where it is found from Leon to Wakulla counties and westward to Santa Rosa county. In the Red List of Magnoliaceae, which documents globally threatened plants within the magnolia family. Magnolia macrophylla subsp. ashei is given the conservation status of "vulnerable", which means it is considered to be facing a high risk of extinction in the wild. SCOTT ARBORETUM COURTESY OF PAT MCCRACKEN 10 Arnoldio 68/1 ‘Gold Crown’, an August Kehr hybrid, bears large, light to medium yellow llowers. Recent Additions, Future Plans The 1990s saw dozens of new cultivars enter the Scott Arboretum's collections from many magnolia purveyors such as Arbor Village Nursery, Gossler Farms, and Fairweather Gardens. In 1998, through Pat McCracken and McCracken Nursery, we received a num- ber of cultivars introduced by noted magno- lia hybridizer Dr. August Kehr. After retiring from the USD A, Kehr started a robust magno- lia breeding program in Hendersonville, North Carolina that resulted in many outstanding cultivars of magnolias. Some of the Kehr cul- tivars included in our magnolia collection are 'Serenade', 'Pink Perfection', and a number of the much-desired yellow-flowered hybrids including 'Gold Crown', 'Golden Endeavor', Magnolia zenii is a critically endangered species in its native range in China. 'Hot Flash', 'Solar Flair', and 'Sunburst'. To create the yellow magnolias Kehr made com- plex crosses using M. acuminata, M. denu- data, M. x brooklynensis, M. 'Elizabeth', M. 'Woodsman' and M. 'Gold Star'. From 2000 to 2010 the Scott Arboretum con- tinued to add dozens of new magnolia taxa to our collection. Many new cultivars of Magno- lia grandiflora and Magnolia viiginiana were added. Several other yellow-flowered magnolias such as 'Yellow Joy', 'Limelight' and 'Golden Rain' were added. In addition, many species magnolias from a variety of sources were acces- sioned, including Magnolia x wiesneri, a hybrid between M. sieboldii and M. obovata; Magnolia zenii which is critically endangered in China where only one population, comprised of 18 Magnolias at the Scott Arboretum 1 1 in’ m i 1*5? Magnolia denudata ‘Swarthmore Sentinel’ was selected and named for its distinctly upright habit. 12 ArnoIdia6H/l individual trees, exists; and Magnolia wilsonii, which is endangered and only exists in scattered populations in Sichuan, northern Yunnan, and Guizhou, China. Two other additions — Magno- lia lotungensis from China and M. tamaulipana from northeastern Mexico — may prove to be borderline hardy in Swarthmore (USDA zone 6, average annual minimum temperature -10°F to 0°F [-23.3°C to-17.8°C]). In 2009 the Arboretum introduced a new selection of the Yulan magnolia. Magnolia denudata 'Swarthmore Sentinel'. The Arbore- tum originally received a seedling from J. C. Raulston at North Carolina State University, who had received seeds from the Beijing Botanic Garden. From a seedling in 1993, the tree is over 30 feet tall today. On several occasions visiting magnolia experts commented on how upright our particular clone was. Therefore, we decided to name this selection 'Swarthmore Sentinel' for its fastigiate habit. Over the last 81 years we have accessioned 502 magnolias at the Scott Arboretum. Today the collection holds 165 different taxa. The Scott Arboretum's collection is recognized as a national magnolia collection through the American Public Garden Association's North American Plant Collections Consortium (NAPCC). According to the APGA "The North American Plant Collections Consortium is a network of botanical gardens and arbo- reta working to coordinate a continent-wide approach to plant germplasm preservation, and to promote high standards of plant collections management." The Scott Arboretum will be working with approximately 20 other insti- tutions across North America, including San Francisco Botanical Garden, Quarryhill Botan- ical Garden, University of British Columbia Botanical Garden, the Bartlett Arboretum, and Atlanta Botanical Garden to create a consor- tium of institutions to oversee the preservation and conservation of Magnoliaceae germplasm. This group will also be part of the NAPCC and administered through the APGA. Once formed, this Magnolia Curatorial Group will partner with the Magnolia Society Interna- tional to target both wild species and cultivar groups which need to he preserved in botanic gardens and arboreta. The Scott Arboretum Magnolia 'Charles Coates’ is an unusual hybrid between M. sieboldii and M. tripetala. will also continue to grow its own collections. We currently have 72 magnolia taxa growing in a nursery, and once these reach specimen size they will he transplanted to garden sites throughout the arboretum. In 2015 the Scott Arboretum plans to host the international meeting of the Magnolia Society International. Bibliography Callaway, D.I. 1994. The World of Magnolias. Timber Press, Portland, Oregon. Gardiner, I. 2000. Magnolias: A Gardener’s Guide. Timber Press, Portland, Oregon. Liu, Y.H. 2004. Magnolias of China. Hong-Kong, Beijing Science & Technology Press. Treseder, N.G. 1978. Magnolias. Faber and Faber, Limited, London and Boston. Wister, I.C. Swarthmore Plant Notes 1930-1954, Volume 1, Part 1 . pp. 80-88. Yagoda, B. 2003. The Scott Arboretum of Swarthmore College — The First 75 Years. The Donning Company Press. Andrew Bunting is Curator of the Scott Arboretum of Swarthmore College in Swarthmore, Pennsylvania. Excerpts from Wild Urban Plants of the Northeast: A Field Guide Peter Del Tredici EDITOR'S NOTE: E ver wonder what kind of tree that is, the one growing from a crack in the asphalt parking lot at work? Or what that tangled vine engulfing the slope by the subway station might be? Wild Urban Plants of the Northeast: A Field Guide, written by long-time Arnold Arboretum researcher Peter Del Tredici, may have your answer. Del Tredici's goal with this book is "to help the general reader identify plants growing spontaneously in the urban envi- ronment and to develop an appre- ciation of the role they play in making our cities more livable." Many of the 222 plants featured in the book could be called weeds, and some are notoriously inva- sive. The author eschews these labels, however, pointing out that in many urban/suburban areas the environment has been so radically altered (think non-native fill soils, soil compaction and contamina- tion, impermeable pavement, and pollution) that the presence of any plants has benefits. This handy guide is organized by plant families and includes both woody and herba- ceous plants. Numerous color photographs and extensive information is provided for each species, including place of origin, descriptions of vegetative, flower, and fruit characteris- tics, and habitat preference. Some fascinating details emerge from the "Cultural Signifi- cance" subsections — for example: "During World War II, the silky seed hairs [of common milkweed, Asclepias syriaca] were used as a substitute for kapok to fill "Mae West" life vests. Between 1943 and 1945, a million such flotation devices were filled with the floss from some 24 million pounds (11 million kilograms) of milkweed pods." Following are half a dozen plant species featured in the book. Reprinted from; Peter Del Tredici, Wild Urban Plants of the Northeast: A Field Guide. Copyright © 2010 by Cornell University. Used by permission of the publisher, Cornell University Press. 374 pages. ISBN 978-0-8014-7458-3. 14 ArnoIdia68/l Toxicodendron radicans (L.) Kuntze Poison Ivy Synonyms: Rhus radicans, Rhus toxicodendron, poison vine Life Form: deciduous vine; up to 50 feet (15 m) long Place of Origin: eastern North America \"egetative Characteristics: This ubiquitous and highly variable vine can climb tall trees, grow as a ground cover, or form a dense, spreading shrub. Re- gardless of its growth habit, all of its branches have a distinct horizontal orienta- tion. Ihe older climbing stems produce conspicuous aerial roots (the meaning of the w'ord radicans) that give them a “bearded” appearance. The alternate, com- pound leaves are composed of 3 glossy leaflets (source of the old warning “leaves of three, let them be”), each about 4 inches (10 cm) long with smooth or coarsely toothed margins; the terminal leaflet always has a petiole while the lateral leaflets are nearly sessile. Leaves of plants growing in the shade turn dull yellow in fall; plants in full sun turn bright red. Flowers and Fruit: Poison ivy produces clusters of inconspicuous 5-petaled, yel- lowish green, insect-pollinated flowers in the axils of the leaves from May through June on separate male and female plants. The berries on female plants turn from green to gray to white when they mature in September. Germination and Regeneration: Fruits are eaten by birds, and seeds germi- nate beneath their roosts. Established plants spread by underground rhizomes and stems that root where they touch the ground. Habitat Preferences: Poison ivy grows best in moist soils in shade or full sun, but can also be found in dry, sandy sites. Its tolerance of high salt concentrations accounts for its abundance near the ocean as well as along busy roadsides. In the urban environment it is common on rock outcrops and stone walls; climbing up telephone poles, buildings, and chain-link fences; along unmowed highway banks and railroad tracks; and climbing up tree trunks in moist or dry woodlands. Ecological Functions: Tolerant of roadway salt and compacted soil; food and habitat for wildlife; erosion control on slopes. Cultural Significance: Touching any part of this plant, in summer or win- ter, causes allergenic dermatitis in 60-80% of people. The offending ingredient is urushiol, which is located in the sap. Once absorbed through the skin it causes a characteristic itchy rash within a day or two of contact. Poison ivy has been used in traditional medicine and was one of the herbs sold by the Shakers to treat chronic paralysis, rheumatism, skin diseases, and bladder paralysis. In 1624 Cap- tain John Smith became the first European to describe the plant, which “being but touched causeth rednesse, itching, and lastly blisters, the which howsoever after a while passe away of themselves without further harm.” Similar Species: Poison ivy is often confused with \'irginia creeper (Parthenocis- sus quinque folia), a climbing vine with 5 leaflets per leaf and nonhairy stems. 42 Woody Dicots: Anacardiaceae (Cashew Family) Wild Urban Plants of the Northeast 15 Poison ivy foliage The mature, horizontal growth habit of poison ivy growing on an iron fence Poison ivy will climb on anything Poison ivy fruits ripen in September Poison ivy in full fall color along a roadside chain-link fence 43 16 Ainoldia 68/1 Paulownia tomentosa ( Ihumb.) Sieb. & Zucc. ex Steudel Princess Tree Synonyms: Paulownia irnperialis, empress tree, karri-tree, royal paulownia Life Form: deciduous tree, up to 6o feet (i8 m) tall Place of Origin: temperate East Asia Vegetative Features: Paulownia is fast-growing, sparsely branched tree with stout, pithy twigs. On mature trees the opposite, heart-shaped leaves are 6-12 inches (12-30 cm) long and nearly as wide, and are covered with velvety hairs, especially on the undersides; on juvenile trees the leaves can be up to 2 feet (70 cm) long and have 2 small secondary lobes. The leaves fall while green or turn brown after experiencing a hard freeze in autumn. Flowers and Fruit: Prominent clusters of fuzzy brown tlow’er buds develop at the ends of the branches in the fall. The buds remain in a rudimentary state of development throughout the winter, then expand in April or May to produce spec- tacular 2 inch (5 cm) long tubular flowers. Ihe flowers, which are pale violet with dramatic yellow stripes on the inside of the corolla, are pollinated mainly by bees. They are followed by pointed, pecan-shaped woody capsules about 1.25-2 inches (3-5 cm) long that split open to release hundreds of small, wind-dispersed seeds in the fall, 'fhe spent pods often remain on the tree for several years. A mature Paulownia tree can produce up to 20 million seeds per year. Germination and Regeneration: The seeds germinate in spring on bare ground. Mature plants typically produce root suckers, especially following dam- age to the primary trunk. These shoots can arise at a considerable distance from the trunk, and most people assume they are seedlings. Habitat Preferences: Princess tree is a light-demanding, drought-tolerant plant that grows in a variety of disturbed urban habitats, including vacant lots, chain- link fence lines, pavement and masonry cracks, rock outcrops, and highway and railroad banks. This species is currently most abundant in the mid-Atlantic region but can be expected to move farther north as the climate becomes warmer. Ecological Functions: Heat reduction in urban areas; tolerant of roadway salt and compacted soil; erosion control on slopes; soil building on degraded land. Cultural Significance: Paulownia was introduced into North America in 1844. Its spread throughout the East was supposedly facilitated when seeds used as pack- ing material to protect imported Chinese porcelain were discarded. The species is often hyped in Sunday newspaper supplements as a “wonder tree” that grows 6 feet (2 m) a year. Its light, fine-grained wood is highly valued in Japan for making a variety of specialized items. Similar Species: Hardy catalpa {Catalpa speciosa) has smooth leaves and long, cigar-shaped fruits. 102 Woody Dicots: Scrophulariaceae (Figwort Family) Wild Urban Plants of the Northeast 17 Princess tree seedling colonizing an abandoned building in New London, Connecticut Growth habit of a spontaneous princess tree in New London, Connecticut Princess tree saplings growing in good conditions produce huge leaves 103 18 Arnoldid 6 H /1 Vitis riparia Michx. Riverbank Grape Synonyms: frost grape, wild grape Ijfe Form: deciduous woody vine; climbing up to 6o feet (i8 m) Place of Origin: eastern North America V^EGETATiVE CHARACTERISTICS: Riverbank grape produces simple, alternate leaves with 3 lobes and relatively few hairs on the underside; they are palmately veined with toothed margins and 4-8 inches (10-20 cm) long. Ihe vines climb by means of forked, coiling tendrils that are produced along the stem opposite the leaves. With age, the dark brown stems can become several inches (5-15 cm) thick with bark shedding off in thin strips. Leaves turn yellow in the fall. Flowers and Fruit: Separate male and female plants produce inconspicuous chains of greenish yellow, insect-pollinated flowers in late spring to early summer; they arise in the axils of the leaves and are about 4 inches (10 cm) long. The purple- black fruits are smaller than cultivated grapes, about 0.25-0.5 inch (6-12 mm) in diameter, and are produced abundantly by female plants in the fall. Cermination and Regeneration: Riverbank grapes are eaten by a variety of birds, and the seeds germinate freely under their roosts; trailing stems root where they touch the ground. Habitat Preferences: Seedlings are highly shade tolerant; once they reach the sunny forest canopy the vines spread out and begin flowering. Wild grapes are vigorous climbers that can easily overwhelm adjacent vegetation. In the urban environment they are common in the understory of moist woods and thickets, along the banks of streams and rivers, climbing chain-link fences, and on roadside guardrails. Like most vines, wild grapes grow best when their roots are situated in moist, shady soil and their leaves are in full sun. Ecological Functions: Tolerant of roadway salt; food and habitat for wildlife; erosion control on slopes. Cultural Significance: Ihe fruit is edible and makes excellent jelly. Native Americans made a tea made from the leaves for medicinal use. Established wild grapes can be very destructive to forest trees, particularly when weighted down by heavy, wet snow or ice. Related Species: Ihe leaves of fox grape {Vitis labrnsca L.) have a dense cover- ing of brownish or whitish hairs on the underside, giving them a rusty or grayish appearance when they blow in the wind. 'Ihe fruits are large, about 0.75 inch (2 cm) in diameter, and sweet. Ihis species is one of the parents of the famous hybrid ‘Concord’ grape developed in 1852 by Ephraim Bull of Concord, Massachusetts. 1)6 Woody Dicots: V'itaccae (Cirape Family) Wild Urban Plants of the Northeast 19 Riverbank grape on a telephone line in Detroit Riverbank grape overwhelming adjacent vegetation Tangle of riverbank grape stems Riverbank grape foliage Riverbank grape fruits The woolly undersides of tox grape leaves are distinctive J17 20 Arnoldia (iH/l Daucus carota L. Wild Carrot Synonyms: Queen Anne’s lace, bird’s nest Life Form: herbaceous biennial; up to 3-4 feet (1-1.3 rn) tall Place of Origin: Eurasia and North Africa Vegetative Characteristics: Wild carrot is a tall, slender plant with finely dis- sected, pinnately compound foliage that has an aromatic, carrot-like odor. Dur- ing its first year the plant forms a rosette of bipinnately compound leaves — up to 6 inches (15 cm) long — that remain green through the winter; the second year it sends up a tall flowering stalk with alternate leaves. 'Ihe stout, whitish taproot is difficult to pull out of the ground. Flowers and Fruit: Wild carrot produces numerous lacelike white flowers in flat-topped, terminal clusters (umbels) from June through September; they can be insect- or self-pollinated. About one in four plants has a single deep purple flower (the “fairy seat”) in the center of the cluster xif all-w’hite flowers. As the seeds de- velop, the umbels close up and develop a form resembling a bird’s nest. 'Ilie tiny seeds are covered with numerous barbs that facilitate their dispersal by animals. A single plant can produce up to 4,000 seeds, and the tall stalks are often bent over by their weight. Germination and Regeneration: Ifte seeds germinate readily on disturbed, sunny sites in spring. FIabitat Preferences: Wild carrot tolerates full sun and dry soil. It is common in abandoned grasslands and urban meadows, vacant lots, rubble dumps, rock outcrops, stone walls, roadsides, and railroad rights-of-way. In its native European habitat it is common in coastal meadows. Ecological Functions: Disturbance-adapted colonizer of bare ground; tolerant of roadway salt and compacted soil; food for wildlife. Cultural Significance: Seeds of w’ild carrot have long been used in European traditional medicine as a “morning-after” contraceptive, and in India to reduce female fertility. Indeed, Dioscorides’ first-century herbal, De Materia Medica, clearly describes its anti-fertility properties. The use of wild carrot as a contracep- tive has been documented in the Appalachian Mountains of North Carolina as w'ell, passed down through oral tradition (Riddle, 1999). The plant has also been used as a diuretic to cure kidney and bladder stones and to eliminate worms. Al- though it is considered the ancestor of the domestic carrot, the roots are barely edible. In American Weeds and Useful Plants (1859), Darlington interpreted the presence of this plant as a sign of moral weakness: “When it gets on the premises of a careless, slovenly farmer, it soon multiplies so as to become a source of annoy- ance to the whole neighborhood.” 122 Herbaceous Dicots: Apiaccac (Carrot Family) Wild Urban Plants of the Northeast 21 Wild carrot flowering on a roadside Wild carrot growth habit Developing seeds of wild carrot Wild carrot flower head with “fairy seat” in the center Wild carrot foliage 123 22 Arnoldio 68/ 1 Chenopodium album L. Common Lambsquarters Synonyms: fat hen, pigweed, mealweed, goosefoot, bacon-weed, wild spinach Life Form: summer annual; up to 6 feet (2 m) tall Place of Origin: Europe Vegetative Characteristics: Ihe stems have conspicuous grooves and are usually green, but sometimes show some purple coloration at the point where the branches are attached, the plant branches freely and develops a broad, pyramidal shape at maturity. Ibe alternate leaves are dull green, 2-4 inches (5-10 cm) long, roughly triangular to rhomboidal (hence the common name goosefoot), and have irregular teeth and gray to white, “mealy” undersides. 'Ihe whole plant has a semi- succulent appearance and sometimes turns purplish at the end of the growing season. Lambsquarters produces a short, tenacious taproot. Flowers and Fruit: Large, pale green inflorescences terminate the branches in late summer; the bisexual flowers lack petals, are inconspicuous, and are mainly self-pollinated. 'Ihe fruits are tiny, bladderlike structures containing a single seed. A large plant can produce up to 75,000 seeds. CiERMiNATiON AND REGENERATION: Seeds fall to the ground at maturity and germinate in early summer; they are also eaten and dispersed by ground-feeding birds. Buried seeds can remain viable in the soil for decades if not centuries. FIabitat Preferences: Lambsquarters tolerates a wide variety of soil types and moisture and light regimens, but reaches its full potential in rich soil. 'Ihe plant is noteworthy for its ability to remain green after other plants have “browned out” from drought or frost. It is common in all sorts of disturbed sites, including neglected ornamental landscapes, minimally maintained public parks, vacant lots, rubble dumps, small pavement openings, chain-link fence lines, rock outcrops, stone walls, unmowed highway banks and median strips, and railroad rights-of-way. Ecological Functions: Tolerant of compacted soil; food and habitat for wildlife; soil building on degraded land; phytoremediation in degraded urban landscapes by absorbing heavy metals (zinc, copper, and lead) and binding them to organic matter. Cultural Significance: Young lambsquarters shoots are edible in the spring after the fine powder that typically covers the leaves is washed away. In times of famine in Europe the seeds were boiled to make gruel or baked into bread (Na- poleon and his troops had to live on this at times). 'Ihe grain quinoa, which has recently become popular as a health food, is the seed of Chenopodium quinoa, a species cultivated at high elevations by the Incas. Related Species: Mexican tea or wormseed {Chenopodium ambrosioides L.) is an upright plant that can grow up to 3 feet (1 m) tall and is native to Central and South America. It produces small, bright green, narrow leaves with wavy margins; while it grows best in full sun, it tolerates shade. Ihe foliage emits a pungent camphor or anise-like odor when crushed, and the seeds have long been used to expel worms, especially in children. Mexicans call the plant epazote and use it as an aide to di- gestion and typically add it to chili sauces and bean dishes to reduce flatulence. 202 Herbaceous Dicots: Chciiopodiaceae (Goosefoot or Beet Family) Wild Urban Plants of the Northeast 23 Lambsquarters in full flower Lambsquarters flowers Lambsquarters growing between a sidewalk and curb Lambsquarters foliage Lambsquarters seeds are included free of charge in most topsoil Mexican tea growth habit 203 24 Arnolciid 6 H/} Patticum dichotomiflorum Michx. Fall Panicum Synonym: smooth witchgrass Life Form: summer annual; from 6 inches (30 cm) to 4 feet (1.3 m) tall Place of Origin: eastern North America Vegetative Characteristics: The growth habit of fall panicum can vary from totally prostate (when growing in poor soil) to upright (when growing in rich soil), and its stems display a distinctive zigzag form. The leaf blades are mostly smooth with a conspicuous white midrib; the leaf sheaths are also smooth and typically are reddish purple. The fibrous root system is extremely tenacious. Flowers and Fruit: Fall panicum produces wTnd-pollinated flower panicles from late summer through fall, followed by loose, spreading seed heads that turn purple and then brown with the first frost. Germination and Regeneration: The .seeds germinate readily on bare ground. Habitat Preferences: 'fhis species is very common in the urban environment, especially in sunny sites with compacted soil, including small pavement cracks and under highway guardrails where blacktop and concrete come together. Ecological Function: Disturbance-adapted colonizer of bare ground. Cultural Significance: The presence of fall panicum in cracks in parking lots and sidewalks creates the impression of neglect. Related Species: Switchgrass (Panicum virgatum L.) is a large, clump-forming perennial grass native to North America. It often grows in dry soils along sandy roadsides and at the upland edge of salt marshes and other wetlands. Its dead leafy stems persist through the winter. Because of its ability to produce abundant bio- mass on marginal land — it can grow up to 7 feet (2.1 m) tall — switchgrass is being promoted for cultivation on marginal land as a source of cellulosic ethanol. Many cultivars of this species have been selected for ornamental purposes. 324 Monocots: Poaceae (Grass Family) Wild Urban Plants of the Northeast 25 Fall panicum growth habit Fall panicum taking over an abandoned parking lot Fall panicum in its urban niche Fall panicum in bloom Switchgrass growing in a median strip Switchgrass in bloom 325 Conserving the Dawn Redwood: The Ex Situ Collection at the Dawes Arboretum Greg Payton S ince 1990, the Dawes Arboretum in New- ark, Ohio, has undertaken a large scale ex situ conservation project with Meta- sequoia glyptostroboides, the dawn redwood. Ex situ conservation is defined as the conserva- tion of genes or genotypes outside their envi- ronment of natural occurrence (China, in the case of dawn redwood). There are challenges and limits to ex situ conservation, hut for some threatened or endangered plants and animals it is an essential component in efforts to keep the species from extinction. For a long-term conser- vation project to be successful and sustainable, a large sampling of genetic material is desirable to maintain the existing and potential variation within a particular species. Many attempts at rescue efforts are done on a limited basis, and they hold relatively small numbers of speci- mens due to insufficient space and budgetary limitations. Ideally, ex situ collections should have the capacity to grow the requisite number of individuals essential for preserving the base I);nvn redwoods develop distinctive buttressed trunks with ase. Dawn Redwood at the Dawes Arboretum 11 A specimen with good form and foliage qualities (accession D1993-0249.004). Variations in foliage of trees in the Dawes plantation. All branchlets photographed on October 13, 2009. gene reserve with a goal of capturing as large of a part of the genetic diversity within the species as possible. Some species require rela- tively few individuals to capture that genetic range, while others require much larger popu- lation sizes. Studies of the genetic variation within dawn redwood have been and still are being conducted. Early results indicate that there is a fairly low genetic diversity, although there is some differentiation within the native populations throughout the overall range of the species. Ex situ conservation does have its limits, and ideally it should complement in situ protec- tion in the natural environment. Preserving a native, wild population is the best option, and this should be the primary focus of any conser- vation program. One of the particular problems with ex situ conservation lies in the inevitable environmental differences between the site of origin and the site of the ex situ collection. If plants in the ex situ site are allowed to sexu- ally reproduce, environmental conditions in this new setting favor the selection and sur- vival of the progeny best adapted to that site. Progeny that survive in the ex situ location may have different traits than progeny which would have survived in the original site. While this may have advantages from a horticultural standpoint (e.g. selection of plants with greater cold hardiness or better drought tolerance), it is a disadvantage for most conservation goals. Preserving the genetic diversity of a species ex situ may be best accomplished by maintaining clonal populations. However, seed banking of species with orthodox seeds (seeds that sur- vive drying or freezing) can also be important in securing a species for the future, and there is the advantage that seeds can he stored in a much smaller space than living plants. A combination of both seed hanking and living plants offers the most opportunities for conservation research. GREG PAYTON 28 Arnoldia 68/ 1 Meet Metasequoia filyptostrohoides Dawn redwood [shui-shan in Chinese, meaning "water-fir") is a deciduous conifer similar to bald cypress [Taxodiuni distichimi). The soft, disti- chous needles of dawn redwood are arranged oppositely, easily distinguishing it from bald cypress with its alternate needle arrangement. When dawn redwood — once thought to be extinct — was discovered still growing in south- central China in a mild and wet climate, it was not believed that it would survive in the United States north of Georgia. The provenance testing done since Metasequoia seeds arrived in the United States in 1948 shows that it can sur- vive in USDA Hardiness Zones 5 to 8 (aver- age annual minimum temperature -20 to 20°F [-28.8 to -6.7°Cl) in areas with sufficient rainfall (or with supplemental watering). In its native Sichuan, China, the average rainfall is around 40 inches (100 centimeters) per year but dawn redwood has survived in parts of the United States with lesser amounts of rainfall. The typical form is a large tree, up to 150 feet (45 meters) tall in the wild, pyramidal in youth, becoming more open-crowned with great age. The trunks on older specimens become strongly buttressed. It is fast growing when moisture is available and can add over 3 feet (1 meter) of growth per year. It is helio- philic (requiring full sun), which has limited its use as a commercial timber tree since it does not grow well in competition. Many millions of dawn redwoods have now been planted throughout China, but the condi- tion of the native population has remained stag- nant. The 2009 lUCN Red List of Threatened Species gives dawn redwood a status of critically endangered, saying that the few remaining trees have been protected but that the habitat has not been, and there are poor prospects for natural regeneration. The valleys the tree prefers have been denuded of vegetation and mature trees are often limbed up — all the way to the top — for firewood. Seedling reproduction is unlikely in this altered environment. In the past, natural seeding was also hampered because the seeds were collected and sold by farmers for various uses such as timber plantations. This practice has become less common in recent years, since An example of a plant that exists only ex situ is Franklinia alatamaha, Franklin tree. It is believed to have been extirpated from its native range (Georgia, in the southeastern United States) by the early nineteenth cen- tury. Fortunately, botanists John and William Bartram found and later col- lected and propagated Franklin tree in the late eighteenth century, and the species still survives in cultivation today. It blooms from late summer into autumn, and flowering often overlaps with fall foliage color. other Chinese conifers have provided lumber of greater quality. In addition, propagation from cuttings has proven to he advantageous for pro- ducing new plants. Recent surveys indicate that 5,396 native trees (of all ages) still remain in the native range in China. The majority of trees (5,363) grow in western Hubei, while 28 grow in eastern Chongqing. Only 5 trees remain in Hunan. Dawn Redwood at the Dawes Arboretum 29 A Case of Depression and the "Single Tree" Theory In 1983, Dr. John Kuser, a forestry professor at Rutgers University, surmised that cultivated Metasequoia in the United States were suf- fering from inbreeding depression. He said, "Apparently, variation in the amount of genetic load carried by different trees causes some to be incapable of producing fertile self- pollinated seeds but allows others to produce a few viable seeds and occasional trees to self quite well." He noted that Metasequoia pollen is wingless and "tends to clump together." The best seed germination was found to occur on trees that had been located advantageously for cross-pollination. At the time, the popular belief was that the poor germination of seedlings was the result of trees in the United States having all originated from the single "type" tree in the village of Maudao, China. However, allozyme variation work done in 1995 showed that the 1947 seeds were not likely to have come from a single iso- lated tree. Furthermore, a copy of a previously unpublished paper by W. C. Cheng dated March 25, 1948 revealed, as stated above, that Hwa had found more than 1000 Metasequoia and about 100 "big ones." Apparently seeds from many Maudao- location of type tree Seed lot 1 Remainder of «edlots. Xingdou»h«n (Natur* Metasequoia Valley ildtgongtfMn'' la(ur« RM*rv«) Hubei Province Chongqing Municipality (formerly Sichuan Frovince) Seed lot 2 (3 "big trees" exist) Estimate nativiTinge(Leng, et al., 2006) ■3> sOi© vyJOii, asiosxjv '7- ~ ;'C .V A A r ■ Map of native dawn redwood distribution and seedlot collection sites. Hunan Province IM lOTO BY BURNEY I lUFF (DAWES ARCHIVES) 30 Arnoldia 68 i I trees had been collected and disseminated. Poor seed set seems to stem from the fact that most seed production outside of China is the result of selfing (due to isolation of specimens). The genetic variation of dawn redwood in China was believed to he much greater than that in the United States, and in 1990 a coop- erative research project on Metasequoia began between Dr. W. 1. Libby at the University of California, Berkeley, Professor Minghe Li at Huazhong Agricultural University in Hubei, China, and Dr. Kuser. A number of organiza- tions contributed to fund the project, and it was at this point that the Dawes Arboretum became involved in provenance testing of Metasequoia. Professor Li collected Metasequoia seeds from several locations in its native range in October 1990. In April 1991, 53 packets of seeds were A dawn redwood specimen from the ori,t;inal 1949 seed acces- sion at the Dawes Arboretum. The photoj>raph is from the early 1990s when the tree was nearly 80 feet (24 meters) tall; a lit’htnini’ strike later took out the top of the tree. A bronze-foliaged specimen in the plantation (accession D1993-023''.005). received at Rutgers University from Profes- sor Li, 52 from trees that still had seed cones, and one packet of mixed seeds. These seed lots were germinated, and only four of the collec- tions produced no seedlings. The remaining 48 "families" were grown on, and complete collections were planned for both Rutgers and Dawes. The remaining seedlings were distrib- uted to nearly 20 cooperating institutions and individuals in the United States and United Kingdom. (The Arnold Arboretum received 125 of these seedlings.) In 1993 the Dawes Arboretum received two shipments of the dawn redwood seedlings from Rutgers. A total of 344 trees were planted in the Dawes plantation. Because of the large size (8 acres [3.2 hectares]) of the Dawes site we were able to plant the trees 25 feet (7.6 meters) apart so no subsequent thinning was necessary. Current Status of the Dawes Collection The LDawes plantation of seedlings from Pro- fessor Li and Rutgers currently consists of 320 trees, which makes it one of the largest living ex situ conservation collections of documented wild-origin dawn redwood trees outside of China. Through 2009, 24 trees have been lost Dawn Redwood at the Dawes Arboretum 31 from this plantation, and one seed lot family has been lost completely from both the Dawes and Rutgers plantations. In 2009, Dawes began contacting other institutions to see what living accessions they had from the original 52 seed lots; 29 new accessions (in the form of vegeta- tive cuttings) representing trees from seed lots where Dawes had few representatives were obtained from these institutions. Since each of these trees was originally grown from seeds, every tree is genetically unique and therefore valuable for its individuality. These cuttings are currently doing well in propagation and will help to provide more genetic stock to add to the diversity of the plantation. The search for additional collections of this Li/Rutgers project is ongoing. Any other mod- ern or historical collection of wild material would be invaluable to add to the Dawes col- lection. One of the seed lots that had no germi- nation was the only lot from Hunan, collected from three individual dawn redwoods there, so we are especially interested in acquiring germ- plasm from the few trees in Hunan. In addition to the plantation trees, Dawes has a few other accessions of wild-collected Metase- quoia: three accessions from the original 1947 seedlings, received in 1950 from Ralph Chaney who presumably got his seeds from Merrill; a grove of 44 trees propagated by cuttings in 1960 from the previous accession; and three individu- als also propagated from the original accession. Into the Future In Metasequoia, female cones (macrosporangi- ate strobili) are typically produced when trees reach a height of 30 to 50 feet (9 to 15 meters ). Male cones (microsporangiate strobili) are not produced until trees are 60 to 83 feet (18 to 25 meters) in height. At this point, neither female nor male cones have been observed on the Dawes Arboretum plantation trees. As the grove continues to grow and seed production begins, the resultant progeny will represent the greatest level of genetic varia- tion within dawn redwood outside of China. The origins of these plantation trees are from across the estimated 800 square kilometer (312 sq. mi.) native range in central China where full cross-pollination is very unlikely. Studies have shown that trees in the native populations show a lack of spatial genetic flow, indicating Wide spacing allows ample room for trees in the dawn redwood plantation. 32 Anioldici 68/1 The author with a witches'-broom on one of the Dawes plantation trees. In 2009, both the genetic and taxonomic (cultivar) collections of dawn redwoods at the Dawes Arboretum were granted full status as a North American Plant Collections Consor- tium (NAPCC) collection. This symbolizes the commitment of the staff and organization to fulfilling the duty of preserving this important collection. As a repository for North America, requests for propagation material are honored for research purposes. Of horticultural interest, there are well over two dozen cultivars of Metasequoia that add to the range of variation within the species. 'Miss Grace' and 'Bonsai' are dwarf selec- tions, 'Jack Frost' has a hint of variegation, and 'Ogon' (syn. 'Gold Rush') is a Japanese cultivar with bright yellow foliage that originated from irradiated seeds. Several cultivar selections could be made from the Dawes plantation trees, as there are some interesting habits and foliage types. Tree heights of the plantation trees are from scarcely 3 feet (1 meter) tall to over 33 feet (10 meters), and habits range from squat and round to tall and narrow with many forms in between. Foliage varies from large and coarse to small and fine, with colors in shades of green and bronze. A witches'-broom — which may yield dwarf forms — has even been found on one specimen. Dawn Redwood at the Dawes Arboretum 33 genetic isolation due to habitat fragmentation (Leng et al. 2007). As stated earlier, natural pollen dissemination is limited. Since these wide-ranging Chinese collec- tions are located together in a single plantation at Dawes, broad genetic combinations could occur. The resultant mixed, open-pollinated seeds could prove useful for horticultural pur- poses as well as for selecting for resistance to any future insect or disease pressures. These seeds would have limited use for some con- servation projects (since they are from mixed meta-populations), but there is potential for controlled crossing within the separate seed lot collections, which would give greater con- servation value. The seeds produced here will be made available to seed banks, researchers, and growers. This collection holds many opportunities for future studies and research to be eon- ducted without traveling to China. The sister population at Rutgers University is currently the subject of an amplified fragment length polymorphism (AFLP) analysis to assess the breadth of the genetic diversity of the collec- tion. Since most of the genotypes at Rutgers are duplicates of dawn redwoods in the collec- tion at Dawes, the data from the AFLP study will pertain to this collection as well. We hope that this successful ex situ collection at the Dawes Arboretum will aid in the conservation and further understanding of this ancient and impressive species. Bibliography Andrews, H.N. 1948. Metasequoia and the Living Fossils. Missouri Botanical Garden Bulletin 36(5): 79-85. Bartholomew, B., D.E. Boufford, and S.A. Spongberg, 1983. Metasequoia glyptostroboides — Its Present Status in Central China. Journal of the Arnold Arboretum 64: 105-128. Ecker, Eisenman, S.W. 2009. Pers. comm. Rutgers University, School of Environmental and Biological Sciences, Department of Plant Biology and Pathology. GSPC. 2002. Global Strategy for Plant Conservation. Montreal: Secretariat of the Convention on Biological Diversity. Hendricks, D.R. 1995. Metasequoia Depression, Sex, and Other Useful Information. Landscape Plant News 6(2): 7-10. Hendricks, D. and P. Sondergaard. 1998. Metasequoia glyptostroboides — 50 years out of China. Observations from the United States and Denmark. Dansk Dendrologisk Arsskrift 6: 6-24. Hsueh, C.-J. 1985. Reminiscences of Collecting the Type Specimens of Metasequoia glyptostroboides. Arnoldia 45(4): 10-18. Hu, H.H. 1948. How Metasequoia, the "living fossil" was discovered in China. Journal of the New York Botanical Garden 49(585): 201-207. lUCN. lUCN Red List of Threatened Species. Version 2009.1. Retrieved October 12, 2009, from www. iucnredlist.org Kuser, I.E., D.L.Sheely, and D.R. Hendricks. 1997. Genetic Variation in Two ex situ Collections of the Rare Metasequoia glyptostroboides (Cupressaceae). Silvae Genetica 46(5): 258-264. Kuser, J. 1983. Inbreeding Depression in Metasequoia. Journal of the Arnold Arboretum 64: 475-481. Leng, Q. et.al. 2007. Database of Native Metasequoia glyptostroboides Trees in China Based on New Census Surveys and Expeditions. Bulletin of the Peabody Museum of Natural History 48(2): 185-233. LePage, B.A., C.J. Williams, and H. Yang. 2005. The Geobiology and Ecology of Metasequoia. Springer. Li, M. 2009, November 1. Pers. comm. Li, X.-D., H.-W. Huang, and J.-Q. Li. 2003. Genetic diversity of the relict plant Metasequoia glyptostroboides. Biodiversity Science 11: 100-108. Ma, J. 2003. On the unsolved mystery of Metasequioa. Acta Botanica Yunnanica (25)2: 155-172. Ma, L 2003. The Chronology of the "Living Eossil" Metasequoia glyptostroboides (Taxodiaceae): A Review (1943-2003). Harvard Papers in Botany 8(1): 9-18. Ma, L 2002. The History of the Discovery and Initial Seed Dissemination of the Metasequoia glyptostroboides, A "Living Fossil". Aliso 21(2): 65-75. Ma, J. and G. Shao. 2003. Rediscovery of the "first collection" of the 'Living Fossil', Metasequoia glyptostroboides. Taxon 52(3): 585-588. Merrill, E.D. 1998-1999. Another Living Fossil Comes to the Arnold Arboretum. Arnoldia 58-59(4-1): 17-19. Sand, S. 1992. The Dawn Redwood. American Horticulturist 71(10): 40-44. Wyman, D. 1968. Metasequoia After Twenty Years m Cultivation. Arnoldia 28( 10-1 1 ): 1 13-122. Greg Payton is the Plant Records Specialist at the Dawes Arboretum in Newark, Ohio. Index to Arnoldia Volume 67 Items in boldface refer to illustrations A Abies spp., and exotic beetles 1; 33, 35 — homolepis, lightning-damaged 4: 22, 22 Abscisic acid 4: 15, 18-19 photosynthesis and 4: 19 Acai juice 3; 23 Acer spp., and exotic beetles 1; 35 — davidii, in China 2: 22, 26 bark 2: inside front cover — Tubrum 'Schlesingeri' 2: 32, inside back cover propagation and redistribu- tion of 2: 32 — saccharum 3: 31 — sutchuenense, in China 2; 27 Ackerman, Dr. William 1: 24, 28 Acorns, features of 4: 2-5, 3-5, 10, 1 1 Adenorachis 3: 21 Aerial photography and mapping 1 : 10-19, 11-15, 17-19 Aesculus spp., and exotic beetles 1: 34,35 Afghanistan, pine from 3: 36, inside back cover Africa, pest beetles from 1 : 33 Agrilus planipennis 1 : 34, 34 Agroforestry 3: 16-17 Aiello, Anthony S., "Seeking Cold- Hardy Camellias" 1: 20-30 Ailuropoda melanoleuca. discovery of 2: 23 Akebia trifoliata, in China 2: 26 Alders, as beetle host 1: 35 Alexander, lohn H., Ill photographs by 1: inside front/back covers; 2: 18 Allium tricoccum 3: 30 Alnus spp., and exotic beetles 1: 35 Alpha-pinene 1: 32 Alpine plants, in China 3: 2-13, 4, 6, 10-11 Ambiosiella fungi 1: 35 American ginseng 3: 28-30, 29-30, 35 Amplified fragment length polymor- phism (AFLP) 4: 7, 9-10 Animal and Plant Health Inspection Service (APHIS), and beetles 1: 31-35 Anoplophora glabripennis 1 : 34, 34 Anteater 2: 30 Anthocyanins 3: 23 Anticancer plants 3: 23, 25 Antioxidant fruit 3: 14-25 commercial potential of 3: 23-25 Ants, leaf-cutter 2: 30 Appalachian Mts., Tennessee 3: 20 Apple, original 2: 20 — fruiting genotypes 2: 20 — quince and 1 : 3 — scab resistance 2: 10, 10, 20 Apple-pear, Asian 4: 28 Apomixis 3: 19, 21, 22, 24-25 Arboriculture and plant hormones 4: 15-19 Arborvitae, as beetle host 1: 35 Arisaema dilatatum, in China 2: 27, 28 Armenia, quince-growing in 1; 5, 5 Arnold Arboretum, Acer rubrum 'Schlesingeri' at 2: 32, inside back cover aerial photographs of 1: 1927, 11; 1929, 13; 1936, 14; 1955, 13, 18; 1967, 12; 1968, 15; 2005, front cover, 11, 15; 2006, 18; 2007, 12; 2008, 17; 2009, 19; 2: 2008, 14 apple selection at 2: 20 autumn interest 2; 32, inside back cover; 4; 23 beetle research at 1: 31-35, 32 Bentham and Hooker sequence at 2: 16 Bradley Rosaceous Collection 1: 14, 44; 2: 16, 20, 20; 4; 22, 24 Bussey Brook Meadow, in aerial photo 1: 14 Bussey Hill, in aerial photos 1: 11, 13, 14 Camellia trials 1: 27 cartography systems 1: 12-19 Centre Street, in aerial photo 1: 14 China expeditions, 1907-1908, 19103: 2-13 cold-hardiness at 3: 36 conifer collection 3: 36; 4: 22 crabapple legacy 2: 14-21, back cover Crataegus at 2: 16 cultivar evaluation 2: 18 Dana Greenhouses, in aerial photos 1: 14 early accessions 1: 44; 2; 16, 19-20 Faxon Pond 2; 32 Forest Hills Gate 2: 16 Foisythia hybrids at 2: 18 Himalayan pine at 3: 36, inside back cover Hunnewell building, in aerial photos 1: 15, 15 Hydrangea paniculate 'Praecox' at 1 : inside covers, 44 introductions 1: 44; 2: 6, 18-21 lapanese and Korean plants at 1 : 27, 44; 2: 16 Leventritt Shrub and Vine Gar- den, aerial photo of 1 : front cover Living Collections surv'ey 1: 15, 17 Master Plan 1: 17 Meadow Road 2: 32 Malus collection 2: 4, 14-21, 14, 16-21, back cover Metasequoia glyptostroboides at 4: 23 model 1: 18-19 Nikko fir, loss of 4: 22, 22 Peters Hill 2: 14, 16, 16, 18, 19, 19, 20 in aerial photos 1: 11-12, 14 Pinus wallichiana at 3: 36, inside back cover plant distribution benefits 2: 20 Prunus at 1: 13; 2: 18; 4: 24 Pyrus 2: 16 pyrifolia at 4: inside covers, 28 Rosaceae blights at 4: 22 sand pear at 4: 28, inside back cover Visiting Committee, 1955 1: 15 "Weather Station Data — 2009" 4: 20-24 Weld Hill in aerial photos 1: 14, 18, 19, 19 winter temperatures 3: 36 Arnoldia. Index to Volume 66 1: 36-43 — and Donald Wvman 2; 19 Index 35 Arnot Teaching and Research Forest 3: 32, 32 Aionia 3: front/back covers, 14-25, 14-18, 22, 24 — aibutifolia 3: 14-15, 15-19, 21-22, 24 flowers 3:15 foliage 3:15 fruit 3: 14 — fruit chemistry 3: 14, 21, 23-25 crop potential 3: 19-25 — genetics 3: 19, 21, 22, 24—25 — habitat and range 3: 18-19, 18-20, 21 — hybrids 3: 21, 25 — juice products 3: 22-25, 23 — 'Likernaya' 3: 25 — melanocarpa 3: 15-19, 16, 17, 21- 25, 22, 24 foliage 3: 17, 22 fruit 3: front cover, 16, 24 growth habit 3: 21, 22 'Nero' 3: 24, 25 X Sorhus aucuparia 3: 25 'Viking' 3: 24, 25 — mitschuiini 3: 25 — ploidy and apomixis in 3: 19, 21, 22, 24-25 — prunifolia 3: 15, 18-19, 21, 22 X arbutifolia 3:21 X melanocarpa 3: 21 X prunifolia 3:21 — taxonomy 3; 21 and Photinia 3: 21 "Aionia: Native shrubs With Untapped Potential," Mark Brand 3: 14-25, 14-20, 22-24 Ash, as beetle host 1: 34 — borer, emerald 1: 34 Asia, plants from 1: 20-30, 44; 2: 5, 22- 28; 3: 2-13, 36; 4: 28 Asian long-horned beetle (ALB) 1: 34, 34; 2: 29 — medicine, traditional 3: 29-30 Asiatica Nursery [PA] 1: 20-21 Asiniina triloba, fruit of 3: 28, 28, 30 Astilbes, shade-grown 3: 33 Atomic testing 2: 31 Autumn color 2: 32; 4: 23, 28 "Autumn's Harbinger: Acer Rubrum 'Schlesingeri'," Michael S. Dos- mann 2: 32, inside back cover Auxin pathway 4: 15-19 — exogenous 4: 18 B Bachtell, Kris, photo by 2: inside front cover Bacterial diseases 2: 10; 4: 22 Bamboo, in panda habitat 2: 26 Baoxing, plant exploring in 2: 22-28 Bark beetles, in port of Boston 1: 31-32 Basset, Cedric,"ln the Footsteps of Father David" 2: 22-28, 22-28 Bayesian approach 4: 1 1 Beech 3: 31 Beeches, as beetle host 1; 35 Beetle, ambrosia 1: 32 — Asian long-horned (ALB) 1: 34, 34; 2: 29 — emerald ash borer (EAB) 1: 34, 34 — European spruce bark 1: 35 — red-haired pine bark 1: 33, 33 — six-toothed bark 1: 33, 33 Beetles, damaging 1: 31-35, 33-4 emergence and phenology 1: 32,35 fungal vectors of 1: 33, 35 links to information 1: 34 new surveys and trapping meth- ods 1: 32-35 observation of 1: 34 Bene, John 3: 27 Bentham, George 4: 26 Bentham and Hooker sequence 2: 16 Berberidaceae 2: 26 Beresowski (the botanist) 2: 28 Berks, Robert 4: 27 Berry crops 3: 14-25, 28, 30 "'Best' Crabapples [Malus spp.)" 2: chart 9 Betula spp., and exotic beetles 1: 35 “Between Earth and Sky: Our Inti- mate Connections to Trees, ’’ Nalini M. Nadkarni, [excerpt] 2: 29-31 Bible, quince in 1: 3 Binomial nomenclature 4: 26 Biodiversity 2: 22-23, 24, 28; 3: 6, 11-13, 26, 27, 28 Biology and taxonomy 4: 25-27 Birch spp. 3: 36 Birches, as beetle host 1: 34, 35 Birds 2: 6, 10; 3: 14, 16 "Bird's-eye Views: Aerial Photographs of the Arnold Arboretum," Sheila Connor 1: 10-19, 10-19 Black, James W., aerial photography of 1 : 10 , 10 Blackberries 3: 28 Blights and 2009 weather 4: 20, 22 Blooming, premature 4: 24 Blue Ridge Community College 4: 19 Blue stain fungi 1 : 33 Boston 133 Cities Urban Area map- ping program 1:17 Boston port 1:31 invasive beetles and 1: 31-32 Botiyosphaeria obtusa 2; 10 Bourg, Ian C., Ph.D. 2: 28 Brand, Mark, "Aronia: "Native shrubs With Untapped Potential" 3: 14—25 photos by 3: back cover Bristol, Peter 1:21 Brooklyn Botanic Garden 2: 6 Buckeyes, as beetle host 1: 34, 35 Burbank, Euther, and quinces 1: 2, 4, 7, 8 Burma, pine from 3: 36 Burnett, D. Graham 4: 27 Bussey Institute 2: 17 C Calanthe tricarinata, in China 2: 25, 25 California, quinces in 1: 2, 3 Callicaipa japonica 1 : 24 "Camellia Belt" 1: 27 Camellia japonica 1 : 20-30, 22-23, 25-29 'Balustrade' 1: 29 'Bloomfield' 1: 29, 29 espaliered 1: 30 fruit and seed 1: 23 grazing and 1 : 23 'Korean Eire' 1: 28 Korean selections 1 : 24—29, 27, 28, 29 'Longwood Centennial' 1: 28 'Longwood Valentine' 1: 28 'Meadowbrook' 1: 29 'Morris Mercury' 1: 29 winter performance 1 : 20, 24-30 Camellias, hardier 1: 20-30 Campanulaceae 2: 26 36 ArnohIici68/l Campbell, Nichole K., "Searching for Exotic Beetles" 1: 31-35 Canada, ginseng cultivation in 3: 30 Cancer, plants against 3: 23, 25 Caprifoliaceae 2: 25 Cardamine, in China 2: 28 Cargo ships, and pests 1: 31-32, 31 Carnegie Museum of Natural History, beetle collections 1: 32 Carpinus caioliniana 3: 31 — fangiana. in China 2: 26, 27 Cary a spp. 3: 30 — X dunbaiii 3; 32 — graft unions 3: 32, 32 — laciniosa x ovata 3: 32 — ovata 3: 32 — ovalis 3: 32 Caucasus region, quinces of 1:4, 5, 7, 7 Cedars, as term 2: 23 Ceiatocystis spp. 1: 33 — polonica 1:35 C-glucoside vitexin flavone 3: 21 Chaenomeles sinensis 1 : 8 Chanticleer garden 1 : 27 Chengdu Institute of Botany 2: 28 Cherries, as beetle host 1: 35 Cherry, flowering 4: 24 — in secondary growth 3: 32 Chicago area, oaks near 4: 4, 7, 10 Chicago Botanic Garden 4: 27 China, expedition to, 1980 2: 19 — Imperial 3: 11 — travel between Tibet and 3: 2-13 — plants of 1: 30; 2: inside front cover, 15, 16, 19-20, 22-28, 22-23, 25-28; 3: inside front cover, 2-13, 4, 6, 10, 11; 4: 28 Chinese medicine, traditional 3: 29-30 Chokeberry, black 3: front cover, 15-19, 16, 17, 21-25, 22, 24 — commercial potential of 3: 22-25 — comparison of spp. 3: 14-18, chart 19, 21-23, back cover — cultural needs 3: 19, 23 — fruits 3: front cover, 14-25, 14, 16, 24, back cover — habitat and distribution 3: 18-20, 18-20 — ornamental qualities 3: 14-19, 14-17, 22 — populations 3: 21 — propagation 3: 14, 22 — purple 3: 18-19,21,22 — red 3: 14-15, 15-19, 21, 22, 24 — winter interest 3: front cover Chagga people 3: 27 Chloroplast data, and oak hybrids 4: 3 Classification trends 4: 25-27 Clematis, in China 2: 28 Climbing plants 2: 26, 27 Climate change 4: 13 Codonopsis tangshen, in China 2: 26 Cold-hardiness 3: 36 in camellias 1 : 20-30 Computerized records, and mapping 1: 17, 19- Conifers 3: 36; 4: 22 — pests of 1: 31-35 Connor,. lay 1: 19 photographs by 1: front cover Connor, Sheila, "Bird's-eye Views: Aerial Photographs of the Arnold Arboretum" 1: 10-19 Container-growing 3: 33 Convallariaceae 2: 25 Corkscrew willow 3: 35 Cornell University 3: 32; 4: 25 Cornus controversa. in China 2: 25, 26 — kousa, Korean 1: 30 — seiicea, in winter 3: 34 Corydalis anthriscifolia, in China 2: 26 — davidii, in China 2: 26 Cotoneastei moupinensis, in China 2: 28 Crandall, C.S. 2: 20 "Crabapple Cultivars Introduced by Arboretum" 2: chart 21 Crabapple cultivars 2: 2-13, 17-21 Crabapples, at Arboretum 2: 14-21 — bark interest 2: 19-20 — best of 2: chart 9 — breeding and selection 2: 5-7, 14-21 — choosing 6-13 — cultivation 2: 3-7 — description 2: 2-5 — diseases 2: 10, 20 — fruit 2: 3-1 1,4, 5, 8, 10, 11, 13, 17, 19-20, 19 palatability of 2: 10 — longevity 2: 5 — plumleaf 2: 5-6 — problems with 2: 2-3, 6, 7, 10, 13 — seasonal interest 2: 5, 10, 13, 19 — Siberian 2: 19-20 — siting 2: 3, 5, 6-7, 10, 13 — weeping 2: 5, 5-6, 12, 13, 13 "Crabapples. ..With No Apologies," Jeff lies 2: 2-13, 2-8, chart 9, 10-13 Crops, new 3: 14-25, 26-35 medicinal 3: 23, 25, 29-30 ornamental 3: 33-35 Cypiipedium tibeticum 3: 12 Cryptomeria spp., and exotic beetles 1:35 Cunninghamia lanceolata 1: 23, 23 Cuppressaceae 2: 23 Curtis, Ralph, 1922 photo by 2: 16 Cydomalus 1: 4 Cydonia oblonga 1 : 2-9, 2-"^, back cover — "A" clone 1: 5 'Angers’ 1: 5 botany of 1 : 3^, 8 — "C" clone 1: 5 cultivation and uses 1: 2-7 germplasm resources 1 : 3-7, 9 'Champion', 1909 illustration 1 back cover 'Chartar Gyugh' 1: 5 'Fontenay Quince' 1: 5 'Harron' 1 : 6 'Orange', 1922 illustration 1: 4 'Pineapple' 1 : 2, 2, 4 'Smyrna' 1: 4 'Van Deman' 1 : 2 — sinensis 1 : 8, 8 "Cydonia oblonga: The Unappreci- ated Quince," loseph Postman 1 : 2-9, 2-8, back cover Cytokinin pathways 4: 15-19 D Da Pao Shan mountain 3: 12, 13 climate 3: 8, 9, 13 Darw’in, Charles 4: 16, 26 The Power of Movement in Plants 4: 16 Darwin, Francis 4: 16 Dating of trees 2: 30-31 David, Father Armand, discoveries revisited 2: 1, 22-28 — biography 2: 24 Index 37 — portrait 2: 24 Davidia 2: 22 — involuciata. in China 2: 24, 25, 25 Dawn redwood 4: 23 Da Xue Shan Mts. 3: 4, 5, 8-9, 12-13 Daylilies, shade-grown 3: 33 Deforestation 1: 21 Del Tredici, Peter, "The Sand Pear — Pyius pyiifolia" 4: 28 photographs by 1 : inside back cover; 4: inside covers Den Boer, Arie F. 2: 2 Dengchigow mountain 2: 28 Deutzia glomeruliflora. in China 2; 26 Dipelta yunnanensis, in China 2: 25 Dirr, Michael 2: 32; 3: 21 Diseases of pome fruits 1; 4, 6, 7, 8 Disjunct flora 1: 44 Disporum bodinieii, in China 2: 25 Diversification, in black oaks 4: 4—13 Diversity in alpine habitat 3: 6, 1 1-13 Dogwood, in China 2: 25, 26 — red-twig, as woody floral 3: 33, 34 Dormancy, and tree hormones 4: 1 7 Dosmann, Michael S., "Autumn's Harbinger: Acei luhrum 'Schlesing- eri'" 2: 32, inside back cover "Malus at the Arnold Arbore- tum: An Ongoing Legacy" 2: 14-21 Douglas firs, as beetle host 1: 33, 35 Diepanostachyum, in China 2: 26 Dulce de membrillo 1: 4-5 E "Early Bloomer: Hydrangea panicu- lata 'Praecox'," Sue A. Pfeiffer 1: inside front/back covers, 44 Eastern Aerial Surveys, Inc. 1:15 East Mailing quince rootstocks 1: 5 Ecology, and oaks 4: 13 — of forests 2: 29-31; 3: 26-28 Edgar, Mr. [circa 1910] 3: 4, 6, 7 Edible crops, new 3: 14—25, 30-33 Education, experiential 3: 32 Egolf, Don 2: 7 Elms, as beetle host 1: 34 Emerald ash borer 1 : 34, 34 Enkianthus deflexus, in China 2: 25, 25 Epimedium davidii. in China 2: 26, 27 Ericaceae 2: 24, 25 Erwinia amylovoia 1: 6; 2: 10; 4: 22 "Essay on Naming Nature: The Clash Between Instinct and Science,” P.F. Stevens [review] 4: 25-27 Ethanol, in beetle trap 1: 32 Ethylene 4: 15 Euonymus alata. restrictions on 3: 23 — in China 2: 28 Eurasia, quinces in 1: 4—7 Eurasian beetles, damaging 1: 33-35 Europe, quinces in 1 : 4—5, 7 European spruce bark beetle 1: 35 Evolutionary relationships, and oaks 4: 13 and classification 4: 25-27 "Excerpt From Wilson’s China: A Century On," Mark Flanagan and Tony Kirkham 3: inside front cover, 2-13, 3-6, 8-12 Exotic beetles 1: 31-35 Experiential learning 3: 32 "Extraordinary Discoverer of Life" 2: 24 F Fabraea maculata, and quince 1 : 6, 7 Fagus and exotic beetles 1: 35 Fairchild Aerial Surveys, Inc. 1: 10, 11, 18 Fairchild, Sherman Mills 1: 10 Famiglietti, Bob, "2009 Weather at the Arboretum" 4: 20-24 "Farming or Wildcrafting?" 3: 27 Fengtong nature reserve 2: 22, 22, 24-28, 25, 26 Ferns, shade-grown 3: 33 Fertilizing, and tree hormones 4: 18 Fiala, Father John 2: 6, 14 Field-forest ecotone 3: 28 Fir, Nikko 4: 22 — as beetle host 1: 33, 35 Fire blight 1: 6, 7, 8; 2: 10 — and oaks 4: 2 Flanagan, Mark 3: 2, 3 "An Excerpt From Wilson’s China: A Century On. ” with Tony Kirkham 3: 2-13 Forest ecology 2: 29-31; 3: 26-28 — farming, introduction to 3: 26-35 crop selection for 3: 28-30, 33, 35 income potential of 3: 26, 28, 29, 30, 33, 35 — health checklist 3: 27 — non-timber crops from 3: 26-35 — private ownership of 3: 27-28 "Forest Farming," Ken Mudge 3: 26-35, 26-34 Forest Farming Practicum [Cornell] 3:32 Forest Hills Station 1: 12 Forests, North American oak 4: 2-13 Franchet (the botanist) 2: 27 Fraxinus, and exotic beetles 1: 34 Fruit, nutraceutical 3: 14-25 — spot 1: 6, 7 — trees 1: 2-9; 4: 28 Fuji cherry 4: 24 Fuller, Dave 1:19 Fullerview Photography 1:19 Fumariaceae 2: 26 Fungus 1: 33, 35; 2: 10, 20; 4: 20 G "Golden Apple" of antiquity 1: 2-3 Garden and Forest 1 : 44 Genealogical relationships 4: 25-27 Genebank, national system 1 : 6, 7, 9 Gene flow, between oak spp. 4: 7-1 1 interspecific 4: 9 Genera Plantarum [Bentham and Hooker] 4: 26 Genetics, in Aronia 3: 19, 21, 22, 24-25 — in Malus 2: 20 — nut-tree grafts and 3: 32 — of black oak group 4: 2-13 Geographic distance, and oak specia- tion 4: 2-13 — information systems (GIS) 1: 10, 19 Germplasm Resources Information Network (GRIN) 3: 21 Gibberellins 4: 15 Ginseng, American, 3: 28-30, 29, 30 growing 3: 28-30, 32 market for 3: 29-30 medicinal uses 3: 29-30 pricing 3: 30 root 3: 30 soil calcium and 3: 29 Ginsenosides 3: 30 Glaciation, and oaks 4: 13 Gleason, Herbert Wendell 1 : 13 Globalization 2: 29 .^8 Arnoldia 68/1 Goldenseal d; 29, 29 Gongga Shan Mt. (Minya Konka) 3: 4, 5, 8-10 Google Earth 1: 10 GPI Models 1: 18 GPS database, in curriculum 3; 32 Gravitropism 4: 16 Gray, Asa, and disjunct flora 1 : 44 Great Lakes region, oaks in 4: 2-13, map 6 Griffola frondosa 3: 30 Growth processes, and plant hor- mones 4: 15-19 — rate, measuring 2: 30-31 Grunsfield, John 1; 16 H Hardiness, of camellias 1: 20-30 — of crahapples 2: 3 — of hydrangea 1 : 44 — of pines 3: 36 Hardwoods, for mushroom-growing 3: 31 — secondary 3: 32 Harvard Institute for Geographical Exploration 1: 12, 16 Harvard Real Estate 1:17 Hayrapetyan, Vagharshak, Dr. 1: 4 Hellebore, Tibetan 2: 27-28, 28 Hellebores, shade-grown 3: 33 Helleboms chinensis 2: 27-28 — thibetanus. in China 2: 27-28, 28 Hemlocks, as beetle host 1 : 35 Hengduan Shan mountains 3: 4-13 Hen-of-the-woods mushroom 3: 30 Hericium spp. 3: 30, 31 Heucheras, shade-grown 3: 33 Hickory nuts 3: 30, 32 — red pignut 3: 32 — shagbark 3: 32 — varieties and grafts 3: 32 Hill, Rev. Ernest J. Hill 2: 4 "Hill's Oak: The Taxonomy and Dynamics of a Western Great Lakes Endemic," Andrew L. Hipp 4: 2-13, 2-6, map 6, genetic chart , 8-12 Himachal Pradesh, pine from 3: 36 Himalayan National Park 3: 36 Himalayan pine 3: 36, inside back cover Himalayas, Eastern 3: 3, 4-13, 5, 8, 9, 12 — flora of 3: 2-13, 36 Hines Nursery 1: 28 Hipp, Andrew L. "Hill's Oak: The Taxonomy and Dynamics of a West- ern Great Lakes Endemic," 4: 2-13 photo by 4: back cover Hippeastrum 4: 16 Hokkaido 1 : 44 Holboellia, in China 2: 26, 27 Holden Arboretum 1: 21 Honeysuckle family 2: 25 Honeysuckles, in China 2: 28 Honshu 1 : 44 Hood Blimp 1:19 Hooker, Joseph Dalton 4: 26 Hormones, and plant care 4: 15-19 "Hormones and Tropisms" 4: 16 Hornbeam 2: 26; 3: 31 Horsechestnut, as beetle host 1: 34 Hosie, Sir Alexander 3: 1 1 Hostas, forest-grown 3: 33, 33 Howard, Heman 1:18 1959 photo by 2: 17 Hubble telescope camera 1:16 Hubei Province 2: 19; 4: 28 Humanity and trees 2: 29-31 Hun, Chang Yong 1:21 Hybrid, intergeneric 1 : 3-4; 3: 25 — interspecific 3: 21 Hybrization, in oaks 4: 2-13 Hydrangea, panicle 1 : 44 Hydrangea paniculata 'Praecox' 1: inside front/back covers, 44 Hydrastis canadensis 3: 29, 29 Hylurgus ligniperda 1 : 33, 33 UK lies, Jeff, "Crabapples...With No Apologies" 2: 2-13 Illinois, oaks in 4: 2-13 Incarvillea delavayii: 13 — in a Tibetan scene 3: 1 1 "Index to Arnoldia, Volume 66" 1 : 36-43 India, pine from 3: 36 Indiana, spruce beetle in 1: 35 International Council for Research in Agroforestry (Kenya) 3: 27 "In the Footsteps of Father David," Cedric Basset 2: 22-28, 22-28 Iowa, Aronia in 3: 32 Iowa State University 2: 13 Ips sexdentatus 1: 33, 33 — typographus 1: 35 spruces killed by 1: 35 Iran, quince gcrmplasm in 1: 7 Ironwood 3: 3 1 Irrigation, and hormones 4: 18-19, 18 Japan, plants from 1: 30, 44; 2: 16 Japanese spicebush 1 : 24 Johnson, Ethan W. 1: 15 Joyce Kilmer Park, in aerial photos 1: 1936, 14; 1955, 18 Juglans spp. 3: 30 Juice crops, sustainable 3: 14—25 June, Chang Yong 1:21 Junipers, alpine 3: 8 Kabul, pine from 3: 36 Kangding expedition 3: 2-13, 10 Kazakhstan wild apple 2: 20 Kelley, Susan 1:17 Kenya, agroforestry center 3: 27 Kew's Arboretum 3: 2 — expeditions to Himalayas 3: 2-13, 36 Kilimanjaro, agroforestry on 3: 27 Kirkham, Tony 3: 2, 3 "An Excerpt From Wilson's China: A Century On. " with Mark Flanagan 3: 2-13 photo by 3: inside front cover Knox, Charles 1: 2 Koller, Gary 2: 32 Korean camellias 1: 20-30, 23, 25-30 — climate 1: 20-25, 30 — mountain ash 1: 24 Kuan Hsien, travelling in 3: 1 1-12 L Ladyslipper, Tibetan 3: 12 Lampshade poppy, quest for 3: 2, 4-7 Landscape ornamentals 1 : 2-9, 20-30, 44; 2: 2-21, 32; 3: 14-25, 36; 4: 28 Land-use 3: 26-35 Larches, as beetle host 1 : 33, 35 Lardizabalaceae 2: 26 Larix spp., and exotic beetles 1 : 33, 35 Latin America, quinces in 1: 4-5 Leaf-spot 1 : 6, 7 — frogeye 2: 10 Leaves, soil nutrients in 3: 29 Lentinula edodes 3: 28, 30 Index 39 Leptographium spp. 1: 33 Lian Lua Shan mountains [Tibet] 3: 5 Lightning damage 4: 22 Lilium lophophoTum 3: 13 Lindera obtusiloba. autumn foliage 1: 24 Lmdgren funnel trap 1 : 32, 33, 35 Linnaean system and new trends 4: 26-27 Linnaeus, Carolus, statue of 4: 27 Lion's mane mushroom 3: 30, 31 Liiiodendion tulipifeia 3; 31 Lhasa, travelling to 3: 2-5 Longwood Gardens, camellias at 1: 28 Lonicera, in China 2: 28 Lyon Botanical Garden 2: 28 M MacDaniels, Lawrence 3; 32 "MacDaniels Nut Grove: A Unie]ue Educational Site" 3: 32, 32 Magnolia, in China 2: 28 — lihiflora. in China 2: 23 Maine, chokeberry in 3: 19 — exotic beetle in 1: 35 Maitake mushroom 3: 30 Malus 1: 3; 2: front/back covers, 2-21 — 'Adirondack' 2: 7, 7, 9 — 'Aldenhamensis' 2: 2 — 'Almey' 2: 2 — 'Amberina' 2: 5 — 'Antonovka' rootstock 2: 18 — apple-scab and 2: 3, 10, 10 — Arboretum legacy of 2: 14-21, back cover — X atrosanguinea 2: 1 — baccata 2: 5, 19-20 'Columnaris' 2: 21 'Jackii' 2: 21 — 'Barbara Ann' 2: 21 — bark interest 2: 19-20 — 'Blanche Ames' 2: 17, 21 — 'Bob White' 2: 10, 10, 21 — 'Camzam' (Camelot®) 2: 7, 8, 9 — 'Cardinal' 2: 7, 9 — centenarian 2; 16 — 'Cinzam' (Cinderella®) 2: 7, 9 — 'Coralcole' (Coralburst®) 2: 7, 7 — 'David' 2: 7, 8, 9 — diseases and resistance to 2: 3, 6, 9-10, 20 — documentation 2: 16 — 'Dolgo' 2: 10, 10 — 'Donald Wyman' 2: 8, 9, 10, 11, 19, 19, 21 — 'Dorothea' 2: 2, 21, 21 — 'Doubloons' 2: 13 — dwarf 2: 7, 18 — floribunda 2: 2, 4, 6, 9, 10, 16 'Exzellenz Thiel' 2: 6 Selection #821 2: 20 — flowering display 2: 2, 2^, 4, 6-8, 9, 12-19, 13, 17, 19, 21 — foliage 2: 3, 5, 9-10 — fruiting 2: front/back covers, 3, 4, 5, 5-6, 8, 9-10, 10, 11, 13, 19, 19, 20 preserves from 2: 10 — fruitless cultivars 2: 10 — genetics and selection 2: 14-17, 20 — halliana 2: 20 — hardiness 2: 3 — 'Henrietta Crosby' 2: 17, 21 — 'Henry F. Dupont' 2: 17, 21 — 'Hopa' 2: 3 — 'Huber' (Royal Fountain®) 2: 13 — hupehensis 2: 16, 17, 20 — 'Indian Magic' 2: front cover, 10 — ioensis 'Palmeri' 2: 21 — 'farmin' (Marilee®) 2: 10 — 'lewelcole' (Red Jewel™) 2: 8, 9, 10 — 'JFS-KW5' (Royal Raindrops®) 2: 9, 13 — 'Katherine' 2: 21 — lancifolia hybrids 2: 18 — 'Lanzam' (Lancelot®) 2: 7, 9 — 'Liset' 2: 2, 2, 6 — 'Lollizam' (Lollipop®) 2: 7 — longevity 2: 16 — 'Louisa' 2: 9, 13, 13 — 'Mary Potter' 2: 17, 17, 21 — 'Orange Crush' 2: 6, 6, 9 — pedicel variation 2: 19 — 'Pink Pearl' 2: 21 — 'Prairie Maid' 2: 5, 9 — 'Prairifire' 2: 9, 10, 12, 13 — 'Prince Georges' 2: 21 — 'Profusion' 2: 2 — prunifolia 2: 5-6 'Pendula' 2: 6 — 'Purple Prince' 2: 7, 9 — 'Radiant' 2: 3 — 'Red Jade' 2: 2, 5, 5-6, 12, 13 — 'Red Swan' 2: 5, 6 — X Tobusta 'Erecta' 2: 21 — rootstock effects 2: 20 — sargentii 1:6, 16 'Rosea' 2: 7, 17, 21 'Select A' (Firebird®) 2: 7 'Tina' 2: 7 — 'Satin Cloud' 2: 5 — Sax experimental hybrids 2: 18, 18 — 'Schmidtcutleaf' (Golden Rain- drops®) 2: 7, 8, 9 — sieveisii 2: 20 — 'Snowdrift' 2: 10, 11 — 'Spring Snow' 2: 10 — sylvesths hybrids 2: 18 — transitoria, in China 2: 15 — tschonoskii 2: 5, 16 — unnamed #691-52-A 2: 18 — variation of 2: 3 — wasps and 2: 3 — weeping forms 2: 5-6, 12-13, 13 — winter interest 2; 11, 12, 13, 20 — X zumi 'Calocarpa' 2: 21 "Malus at the Arnold Arboretum: An Ongoing Legacy," Michael S. Dosmann 2: 14-21, 14-21 "Malus Mystery" 2: 18 Maple 3: 32, 36 — David's 2: inside front cover, 22 — products 3: 28, 35 — red, cultivar 'Schlesingeri'2: 32, inside back cover — red 3:31 — sugar 3: 31 Maples, as beetle host 1: 35 Maps from photos 1: 10, 12-15, 17-19 March, Sylvester 1:21 Marino, Sergio 1: 18 Maryland, spruce beetle in 1: 35 Maslow, Abraham, human needs concept 2: 29 Massachusetts Department of Conser- vation and Recreation 1: 34 Massachusetts forests 3: 26 Massachusetts Public Works 1:18 Maximowicz (the botanist) 2: 28 Mayr, Ernst 4: 25, 26 Meconopsis x beamishii 3: 7 — X finlayorum 3: 7 — hoiridula 3: 13 40 Arnoldio 68/1 — integrifolia ssp. inlegrifolia, in China 3: inside front cover, 2, 4-7, 4 X grandis 3: 7 X quitnuphneivia 3: 7 — pseudointegrifolia 3: 7 Medicinal crops 3; 29-30 Mediterranean beetles, damaging 1 : 33 Mesopotamia, quince in 1: 3 Mespilus 1 : 4; 3: 21 Metasequoia glyptostroboides, fall color 4; 23 Mexico, oaks native to 4: 3 Meyer, Paul 1: 21, 22, 23, 24 Michigan, EAR in 1; 34 Microbiota decussata cutting 4: 18 Midwest, Aionia in 3: 23 Miller, George 4: 26 Min Shan mountains 2; 1 Missouri Botanical Garden 4: 27 Moichella spp. 3: 30 Morels 3: 27, 30 Morphology, oak speciation and 4: 2-13 — scientific classification and 4; 25- 27 Morris Arboretum, camellia selection at 1 : 20-30, 25-30 Korean expeditions of (1979-1991] 1: 20-24, 20-23 Morton Arboretum, oak research at 4: 4-14 herbarium specimens 4: 3-5, 9 Mountain ash, Korean 1 : 24 — habitats 2: 22-28 Afganistan 3; 36 Burma 3; 36 Maine 3: 19 Tennessee 3: 20 Sichuan/Tibet 3: 2-13, 3, 5, 8, 9, 12 Mt. Emei 2: 26 Mt. Wachusett 3: 26 Mudge, Ken, "Forest Farming" 3; 26- 35 Murray, loseph, "Tree Hormones and Why They Matter" 4: 15-19 Museum of Science 1:16 Mushroom cultivation 3: 28, 30-33, 31, 33 — income from 3: 30 — nutrient process 3: 3 1 — spawn 3: 31, 33 — wild-collected 3: 27 Mutagen breeding 3: 24 N Nadkarni, Nalini M., Dr. 2: 29 "Between Earth and Sky: Our Intimate Connections to Trees" [excerpt) 2: 29-31 Nakai (Japanese botanist) 4: 28 Naming Nature: The Clash Between Instinct and Science [Yoon, reviewed] 4: 25-27 National Arboretum 2: 7 National Plant Germplasm System (NPGS) 1: 6, 7, 9 Native Americans and plants 3: 27, 29 Nebraska, Aronia in 3: 23 Nematode, pinewood 2; 29 New England, hydrangeas in 1 : 44 Newton, Amanda A., 1909 illustra- tion by 1 : back cover New York forests 3: 27-28 Nightshade family, blights 4: 20 Nikko fir 4: 22 Nineteenth-century aerial photogra- phy 1: 10, 10 garden trends 1: 44 Nomenclature, binomial 4: 26 — of Aronia 3: 21 Non-native pests 1: 31-35 North America, flora of 1: 44; 3: 14-25 forest-farming in 3: 27 oaks of 4: 2-13, map 6 pests from 2: 29 North Carolina, chokeberry in 3: 18 Northeast Aerial Photos 1:15 Northeast, versatile shrub for 3: 14-25 reforestation trends in 3: 26, 28 Nuclear data, and black oaks 4: 3 Nursery trade 2: 14, 32 Nut groves 3: 30, 32 Nutraceutical fruit crop 3: 14-25 o Oak 3: 31, 32, 36 — black 4: 5-6, 10-13, 10-11, back cover hybrids 4: 7 petioles 4 1 1 — genome 4: 7-11 — Hill's, disturbance and 4: 13 interbreeding and taxonomy 4: 1-13, 2-5, map 6, genetic chart 7, 9-10 — northern pin 4: 2-13 — pin 4: 5 — red 4: front cover — scarlet 4: 3-10, 4, 6, map 6, genetic- chart 7, 8-9, 12 — white 4: 12 Oaks, as beetle host 1: 35 — black group 4: 2-13, map 6, genetic- chart 7 — white group 4: 2-3 Ohio Valley, camellias in 1: 27 Olmsted style 1:6, 12 Ophiostoma spp. 1 : 33 Orchids, wild 2: 25 Oregon, Aronia in 3: 23 — exotic beetle in 1: 35 — USDA genebank in 1: 7, 9 Ornamentals, forest-grown 3: 33-35, 33, 34 — woody 1: 2-9, 20-30, 44; 2: 2-21, 32; 3: 14-25,36; 4: 28 Osmanthus forest, in China 2: 24 Oyster mushroom 3: 30, 31 P Panax quinquefolius, as crop 3: 28-30, 29, 30 Panda, giant 2: 22, 2.3, 24, 28 Pao-chung, Kao, Prof. 2: 28 Paris fargesii. in China 2: 25 Parks, Clifford, Dr. 1: 24, 28 Pawpaw fruit 3: 28, 28, 30 Pear 1 : 3, 4, 5 — 'Beurre Hardy' 1 : 5 — 'Bradford' Gallery 4: 28 — 'Comice' 1 : 5 — Japanese 1 : 4 — 'Old Home' 1: 5 — quince hybrid 1 : 4, 4 — quinces and 1 : 3-7 — sand, at Arboretum 4: inside covers, 28 fruit of 4: 28 vigor of 4: 28 — tribe 1 : 3 Index 4 1 Pectin 1 : 2; 3: 23 Perennials, pot-in-pot 3: 33, 33 — shade-grown 3: 33 Permaculture 3: 32 Pests 1 : 31-35 Pfeiffer, Sue A., “Early Bloomer: Hydrangea paniculata 'Praecox'" 1: inside front/back covers, 44 Pheneticists, and trends 4: 26 Philadelphia, camellias for 1 ; 20, 24-30 Photinia 3: 21 — floribunda 3: 21 — melanocarpa 3: 21 — pyri folia 3: 21 Photography, aerial 1: 10-19 Photosynthesis and plant hormones 4; 18-19 Phototropism 4: 16, 16 Phytophthoia infestans 4: 20 Picea spp., and beetle damage 1: 33, 35 — forest in Slovakia 1: 35 Pine bark beetle, red-haired 1: 33, 33 — cones for crafts 3: 27, 33 Pine, Eastern white 3: 36 — Himalayan 3: 36, inside back cover — lanceolate 2: 22, 23 — Monterey, with bark damage 1 : 33 Pines, as beetle host 1: 33, 35 — cold hardiness of 3: 36 Pinewood nematode, in Europe 2: 29 Pinus spp., and exotic beetles 1: 33, 35 — excelsea 3: 36 — giiffithii 3: 36 — nepalensis 3: 36 — ladiata, with beetle damage 1: 33 — strobus 3: 36 — thunbeigii 1: 24 — wallichiana 3: 36, inside back cover synonyms for 3: 36 Plant exploring 1: 20-30; 2: 22-28; 3: 2-13 — hormones, and arboriculture 4: 15-19 Plant Protection and Quarantine (PPQ) program 1: 31-35 Pleione limprichtii, in China 2: 25 PleuTotis spp. 3: 30, 31 Ploidy, m Aronia 3: 19-22 Plums 2: 28 Polly Hill Arboretum 1: 27 Pome fruits 1: 2-7 Poppies, lampshade 3: inside front cover, 2, 4—7, 4 Postman, Joseph, "Cydonia oblonga: The Unappreciated Quince" 1: 2-9 Powdery mildew 1 ; 6 Powerline undergrowth 3: 18 Practicum in Forest Farming (Cornell course) 3: 32 Primula seciindiflora 3: 6 Pruning, and hormones 4: 15-19, 17, 19 Prunus spp., in China 2: 28 — incisa f. serrata 4: 24 Pseudocydonia sinensis, in North America 1: 8, 8 flowers and bark 1 : 8 Pseudotsuga spp., and exotic beetles 1:33, 35 Psychology, and trees 2: 29, 30 Pujigou 2: 22, 24-25 Purdue-Rutgers-Illinois Apple Breed- ing program 2: 20 Pyreae 1: 3 Pyronia 1 : 4, 4 — veitchii 1: 4 Pyrus calleryana 'Bradford' 4: 28 — pyrifolia 1: 4; 3: 21; 4: inside covers, 28 — serotina 4: 28 — sinensis 4: 28 Q Quarryhill Botanic Garden 3: 36 Quercus spp., 3: 31 exotic beetles and 1: 35 genetic studies of 4: 5-13 — coccinea 4: 1, 3-10, 4, map 6, genetic chart 7, 8-9, 12 acorns 4: 4 — ellipsoidalis, related spp. and 4: 1-13, 2-5, map 6, genetic chart 7, 9-10 acorns 4: 3, 5, 10 — imbricaria 4: 3 — Lobatae Section 4: 3 — X palaeolithicola 4: 7 — palustris 4: 3 — phellos 4: 3 — pumila 4: 3 — rubra 4: front cover, 3 — shumardii 4: 3 — velutina 4: 3-13, 5-6, genetic chart 7, 10-11, back cover acorns 4: 5, 10-1 1 Quince 1: 2-9, 2-8, back cover — "A" rootstock clone 1: 5 — 'Angers' 1 : 5 — "C" rootstock clone 1: 5 — 'Champion', 1909 illustration 1: back cover — 'Chartar Gyugh' 1 : 5 — Chinese 1: 8, 8 — cold-hardiness 1 : 6, 7, 8 — culinary uses 1: 2, 4-5 — cultivars 1 : 2-7 — diseases or problems 1: 4, 6-7, 8 — flowers and foliage 1: 3 'Fontenay' 1 : 5 — fruit 1 : 2, 2, 4-7, 4-7. back cover — genetics 1 : 4, 5, 6-7, 9 — 'Harron' 1: 6 — history of 1 : 2-6 — hybrids 1: 4 — in Kakheti [Eurasia] 1: 7 — landscape qualities 1 : 2, 5-6, 8 — 'Grange', 1922 illustration 1: 4 — pear hybrid 1 : 4 — pears and 1: 3-7 — pectin content 1: 2 — 'Pineapple' 1 : 2, 2, 4 — propagation and grafting 1: 2-7 — Provence 1 : 5 — pruning 1 : 6 — rootstocks 1: 3, 4, 5, 6, 7 — Shilda variety 1: 7 — 'Smyrna' 1: 4 — 'Van Deman' 1: 2 R Radiation, and plant breeding 3: 24 Radioactive "bookmark" of 1954, and tree-dating 2: 31 Rainforest, dating trees in 2: 30-31 — experience 2: 30 Ramps 3: 30 Ranunculaceae 2: 27 Raspberry, black 3: 28 42 ArnoUlia 68/1 Red osier dogwood 3: i4 — haired pine bark beetle 1: 33, 33 Reed, ["ir. George M. 2: 6 Reeve, Bob, archival photograph by 1: 16 Reforestation trends 3: 28 Rehder, Alfred, 1: 44; 4; 28 — Mains and 2: 16-17 Resistance breakdown, in crabapples 2 : 10 Rheum alexandre 3: 6 Rhododendron, in Sichuan 2: 22, 22 — capitatum 3: 13 — prezwalskii, in Tibet 3: 10 Rhododendrons, alpine 3: 8, 10, 13 Rock, loseph F., and Gongga Shan 3: 4 1926 photo by 2: 15 Root development, and hormones 4; 15-19, 18 — disease fungi 1: 33 Rosaceae 1:3-4, 6; 2: 16; 3: 14, 19 Rose, Nancy, "A Soft Touch: Finns wallichiana" 3: 36, inside back cover photos by: 2: front/inside back covers; 3: front/inside back covers; 4: front cover Royal Botanic Gardens, Kew 3: 2, 36 Rubus spp. 3: 28 Russia, Aronia breeding in 3: 22, 23, 24, 25 Rust diseases 1 : 6 Rutgers, apple breeding at 2: 20 S Sakhalin Island 1: 44 "Sand Pear — Pyrns pyrifolia," Peter Del Tredici 4: inside covers, 28 Sapindaceae 2: 26 Sargent, Charles S. 2: 14, 16, 17, 19,32 Japanese plants and 1: 44 — photography and 3: 10-11 Wilson, E.H. and 3: 2, 10-1 1 Sasaki Associates 1:17 Sax, Karl 3: 36 Mains research and 2: 17-19 Schlesingcr, Barthold 2: 32 Science in the Pleasure Ground exhibit 1: 18-19 Scientific Center for Viticulture (Armemal 1: 5 Scientific classification 4: lS-17 — limits 4: 27 Scott Arboretum 1: 27 "Searching for Exotic Beetles," Nichole K. Campbell 1: 31-35, 31-35 Seasonal changes, and trees 2: 30; 4: 15-17, 19 Seed collection 1: 20, 23-24 "Seeking Cold-Hardy Camellias," Anthony S. Aiello 1: 20-30, 20-30 Shaw, Peter Ashton 1: 15 Shawnee National Forest 4: 8, 12 Shiitake cultivation 3: 28, 30-33, 31, 33 Shipping industry 1: 31-32; 2: 29 Shrubs, centenarian or notable speci- mens 1: 44, inside back cover — native 3: 14—25 Sichuan/Tibet 2: 22-28; 3: 2-13, 3, 5, 8, 9, 12 Sino-American Botanical Expedition [1980] 2: 19 Sinofranchetia chinensis 2: 26 Six-toothed bark beetle 1 : 33, 33 Slovakia, bark beetle in 1: 35 Sochong Island 1: 22, 23 "Soft Touch: Finns wallichiana." Nancy Rose 3: 36, inside back cover Soil 3: 29 — and oaks 4: 13 Solanaceae, blights of 4: 20 Sorbus 1: 4; 2: 28; 3: 21 — alnifolia 1: 24 — aucuparia and Aronia cross 3: 25 South Korea, deforestation in 1:21 expeditions to 1: 20-24, [1984] map 21, 20-23, 30 hardy plants from 1 : 20-30 landscape 1: 21-23 Spiith Nursery [Berlin] 2: 6, 32 Species, biological concept 4: 2, 25 — differentiation in black oaks 4: 2-13 Spicebush, lapancse 1 : 24 Spiraeoideae 1 : 3 Spruce bark beetle 1 : 35 Spruces, as beetle host 1 : 33, 35 Stevens, P.F., "An Essay on Nam- ing Nature: The Clash Between Instinct and Science" [review] 4: 25-27 Stewartia pseudocamellia, branching 4: 15 Storm damage 4: 22 plant hormones and 4: 19 Street trees, beetle damage to 1 : 34 Strontium, radioactive 2: 31 Styrax japonica 1: 24 Sunlight, and plant hormones 4: 16 Sustainable crops 3: 23, 26-35 Swissair Photos -k Surveys 1:15 Sympatry, among oaks 4: 3 Systematist debates 4: 25-27 T Tachien-lu 3: 2, 8, 1 1 Taean Peninsula 1: 21 Taechong Island 1: 20-23 Tagong temple 3: 12, 13 Talltree Arboretum 4: 9 Tang li tzu 4: 28 "Taxonomic Teasers in Aronia" 3: 21 Taxonomy, of Aronia 3: 21 black oaks 4: 2-13 Mains 2: 14, 16-17, 20 — trends in 4: 25-27 Three-ips lure, in beetle trap 1: 32 Thuja spp., and exotic beetles 1: 35 Tibetan Empire 3: 2-3 Tibetan Frontier, circa 1910 3: 2-13, 8 Tibetan region, exploration in 2: 22-28; 3: 2-13 — peoples 3: 2-3, 4, 1 1 Time concepts, and trees 2: 29, 30-31 Tinley Creek Forest Preserve 4: 10 Topping damage 4: 19, 19 Toucans 4: 25 Tournachon, Gaspard-Felix [Nadar] 1 : 10 Trabut, Louis 1 : 4 Trapping beetles, chemistr>' of 1: 32 Tree care, and hormones 4: 15-19 — consumption 2: 29 — dating 2: 30-31 — longevity 4: 15 Index 43 "Tree Hormones and Why They Mat- ter," Joseph Murray 4: 15-19, 15-19 Trees, benefits of 2: 29-30; 4: 15 — centenarian or notable specimens 2: 16, 19, 32, inside back cover; 3: 36, inside back cover; 4; 22, 22, 23, 28, inside back cover — damage to 4: 18, 18, 19, 22, 24 — human needs met by 2: 29-31 — radioisotopes and dating of 2: 31 — seasons and 2: 30; 4; 15-17, 19 — time and 2: 20, 29, 30-31 — urban 4: 15-19 Tnlliums, shade-grown 3: 33 Tropical forests 2: 30-31; 3: 27 Truffles, difficulty of 3: 30 Tsuga spp., and exotic beetles 1: 35 Tubei spp. 3: 30 Tulip poplar 3; 31 Turkey, quinces in; 1 : 4, 6, 7 Turkmenistan, fruit trees in 1 : 4, 7 Tyler Arboretum 1 : 27 uvw "Umwelt" concept 4: 26-27 Urban mapping 1:17 — tree care 4: 15-19 United States Department of Agricul- ture (USDA) 1;2 APHIS and beetles 1:31-35 artwork, circa 1900 1 : back cover GRIN 3: 21 hardiness zone five 3: 36 links 1: 34; 3: 21 NPGS 1; 6, 7, 9 PPQ program 1: 31-35 Plants Database 3: 21 Trans-Gaucasus expedi- tions, recent 1 : 4, 7 US economy and tree consumption 2: 29 US Geological Surveys (USGS) 1:17 US National Agricultural Library, 1909 illustration from 1; back cover US National Arboretum 1: 8, 21 winters at 1; 24 University of Bristol, Long Ashton |Eng.]3:21 University of Connecticut, Aionia research at 3: 14-25 University of Illinois, apple breeding at 2: 20 University of North Carolina, Chapel Hill 1:24 University of Pennsylvania arboretum 1:30 University of Wisconsin, juice crop research 3: 23 Vaccinium corymbosum 3: 23 Vavilov Institutes [Soviet] 1: 7 Veitch Nurseries, E. H. Wilson and 3: 2, 10 Ventuiia inaequalis 2: 10 V, gene, and apple scab 2: 20 Vibuinum bitchuense 1 : 24 — bievitubum. in China 2: 26, 27 — chingii 2: 26 Viburnums 2: 26 Wachusett, view from 3: 26 Walnut 3: 30, 32 — varieties and grafts 3: 32 War, deforestation from 1: 21 Warming trends 4: 24 Washburn, Bradford 1: 16 aerial photography of 1; 12-17, 13, 14 Wasp, yellow-jacket 2: 3 Watersprouts 4: 19 Watson, James 4: 26 "Weather at the Arboretum — 2009," Bob Eamiglietti 4: 20-24, chart 21, 22-24 Weather damage at Arboretum 4: 22 Weather Station Data, 2009 4: 21 Wildcrafting 3: 27, 33 Willow, corkscrew 3: 35 Willows, as beetle host 1; 34 Willowwood Arboretum 1: 27 Wilson, Ernest Henry, hydrangea and 1: 44 lampshade poppy and 3: 2, 4-7 Malus finds 2: 16 sand pear and 4: 28 Tibetan discoveries revisited 3: 2-13 Wilson’s China: A Century On [Elana- gan and Kirkham, excerpt] 3: 2-13 Windsor Great Park 3: 2 Wisconsin, ginseng cultivation in 3: 30 Wood beetles 1: 31-35 — digestion by mushrooms 3: 31 — industry 2: 29 pests and 1: 31-35 — packing as pest vector 1: 31-32, 34; 2; 29 Woody florals 3: 33-35 — ornamentals 1; 2-9, 20-30, 44; 2: 2-21, 32; 3: 14-25, 33, 35, 36; 4: 28 Worcester, MA, ALB in 1:34 World Agroforestry Center [Kenya] 3: 27 World War 11, deforestation from 1:21 nursery trade and 2: 14, 32; 3: 33-35 Wright, Wilbur 1:10 Wyman, Donald, aerial photography of 1: 18 crabapple namesake 2: 8, 9, 11, 19, 19, 21 legacy 2:19 quince opinion 1: 5-6 'Schlesingeri' red maple and 2:32 XYZ Xizang Autonomous Region 3: 3 XyleboTus spp. 1 : 35 — seiiatus 1; 35 Xylotrechus spp. 1: 35 — hircus 1: 35 Ya-jia Pass region 3: 3-10, 3, 6, 8, 9 Yangtze River, Wilson in 3: 11 Yellow Sea islands 1: 20-21, 21-23 Yichang, Wilson in 3: 11 Yinger, Barry 1: 20, 21, 22, 28 Yoon, Carol Kaesuk, at Cornell 4: 25 Naming Nature: The Clash Between Instinct and Science [reviewed] 4: 25-27 Yushania, in China 2: 26 Zacharias, Elizabeth H., Ph.D. 2: 28 Zeiss camera on Hubble 1:16 Zhong, Xiao 3:13 Zhedou Pass 3: 4-5, 12 Compiled by Rosalie Davis A New Plant Introduction from the Arnold Arboretum: Ilex glabra 'Peggy's Cove' John H. Alexander 111 I n October 1988, I was in Nova Scotia for a speaking engagement with the Atlantic Rhododendron and Horticultural Society. Several members were kind enough to show me the sights, including local natural areas. One day we were on a seaside barren, northwest of the fishing village of Peggy's Cove, looking out at the Atlantic Ocean. Crouched between us and the ocean, on a treeless shore that appeared to be more rock than soil, were numerous inkherries. Ilex glabra. I have a special inter- est in this species and had previously collected inkherry cuttings from the New Jersey pine barrens and from compact plants I spotted while driving along Massachusetts roadways. The plants at Peggy's Cove were dwarfed and misshapen by the harsh seaside environment, growing here near the northern extreme of the species' range. I knew that a plant's response to its environ- ment does not necessarily change its genetic makeup, so cuttings from these dwarfed plants might grow into large, robust shrubs when planted in a favorable garden setting. But then again — they might not. My hope was that, after countless generations growing by the shore, their compact habit was now genetic. As plant propagator's like to say, "The best time to take a cutting is when it's offered," so I collected cuttings from plant after plant until my hosts seemed to grow weary from watching me. Thirty-eight of these cuttings — collected from perhaps 12 different plants — were stuck in the Arboretum's propagation house. At least 19 of the cuttings rooted, and all were given the accession number 929-88. Within this group I found what I had hoped to find: a more compact and smallcr-leafed form of Ilex glabra. Named 'Peggy's Cove' in honor of its site of origin, this cultivar is not only compact, hut it also grows well. It has a mounded habit with branches right to the ground. The latter trait is notable since a complaint sometimes heard about the Ilex glabra cultivars 'Densa' and 'Compacta' is that they frequently lose their lower branches. Other surviving plants of this collection either didn't grow well or weren't significantly differ- ent from cultivars already available. At the Arboretum, the original plant of 'Peg- gy's Cove' (now accession number 500-2007-A) is growing in the Leventritt Shrub and Vine Garden, near specimens of 'Compacta' for easy comparison. This 22-year-old plant is now 48 inches (122 centimeters) tall and 60 inches (152 centimeters) wide with a rounded habit. Per- haps it isn't the best example because we have pruned it by harvesting many cuttings from it. Four lightly pruned 8-year-old plants near the Dana Greenhouses (accession number 3-2002) are 22 to 36 inches (56 to 91 centimeters) tall and 30 to 45 inches (76 to 114 centimeters) wide. 'Peggy's Cove' is a female, producing the typical small black fruits of this species (if polli- nated by a nearby male Ilex glabra). The leaves of 'Peggy's Cove' are dark green and smaller than the average inkherry leaf. 'Peggy's Cove' inkherry grows best in full sun and tolerates light shade, hut may stretch a bit and become less compact if in too much shade. Like many hollies, it prefers acidic soils that are evenly moist. Winter damage to leaves of this evergreen has been slight at the Arboretum. 'Peggy's Cove' is probably no hardier than what is typical for the species: USDA zone 5 (aver- age annual minimum temperature -20 to -10°F [-28.8 to -23.4°C]). It is currently in the early stages of commercial production. Acknowledgments Many thanks to lohn Weagle, Stanley Dodds, Walter Ostrom, and the late Captain Richard M. Steele. It was these folks who were instrumental in getting me to Nova Scotia and to that barren coast where I found Ilex glabra 'Peggy's Cove'. A registration description of this cultivar was published in the Holly Society Journal. 2008, 26(21: 10-11. lohn H. Alexander 111 is Plant Propagator at the Arnold Arboretum. The Magazine of the Arnold Arboretum i i -i ** ji < VOLUME 68 NUMBER 2 CONTENTS The Magazine of the Arnold Arboretum VOLUME 68 • NUMBER 2 • 2010 Amoldia (ISSN 0004-2633; USPS 866-1 00| is published quarterly by the Arnold Arboretum of Harvard University. Periodicals postage paid at Boston, Massachusetts. Subscriptions are $20.00 per calendar year domestic, $25.00 foreign, payable in advance. Remittances may be made in U.S. dollars, by check drawn on a U.S. bank; by international money order; or by Visa, Mastercard, or American Express. Send orders, remittances, requests to purchase back issues, change-of-address notices, and all other subscription-related communica- tions to Circulation Manager, Amoldia, Arnold Arboretum, 125 Arborway, Boston, MA 02130- 3500. Telephone 617.524.1718; fax 617.524.1418; e-mail arnoldia@arnarb.harvard.edu Arnold Arboretum members receive a subscrip- tion to Amoldia as a membership benefit. To become a member or receive more information, please call Wendy Krauss at 617.384.5766 or email wendy_krauss@harvard.edu Postmaster: Send address changes to Amoldia Circulation Manager The Arnold Arboretum 1 25 Arborway Boston, MA 02130-3500 Nancy Rose, Editor Andy Winther, Designer Peter Del Tredici, Contributing Editor Editorial Committee Phyllis Andersen Peter Del Tredici Michael S. Dosmann Kanchi N. Gandhi Copyright © 2010. The President and Fellows of Harvard College A 7l2e ARNOLD '^pARBORETUM of HARVARD UNIVERSITY 3 The Case for Plant Exploration Peter Del Tredici 4 The Return to China, Mother of Gardens Paul W. Meyer 12 Sharing and Enjoying the Joint Botanical Expeditions He Shanan i6 Traveling in China Photo Features 20 By the Numbers: Twenty Years of NACPEC Collections Anthony S. Aiello and Michael S. Dosmann 40 Planning Future NACPEC Plant Exploration: Challenges and Opportunities Kunso Kim, Kris Bachtell, and Kang Wang 48 Plant Profiles Paul W. Meyer, Michael S. Dosmann, Carole Bordelon, Douglas Justice, Peter Del Tredici, Sandra L. Anagnostakis, Anthony S. Aiello, Kris R. Bachtell and Olivia Siegel, Richard T. Olsen and Joseph H. Kirkbride, Jr. Eront cover: Morning in Hong He Gu Forest Park during the 2008 NACPEC expedition to Shaanxi, China. Photo by Anthony Aiello. Inside front cover: Two young vendors selling hard- boiled eggs cooked in a natural hot spring near Changbai Shan, Jilin, China, in 1997. Photo by Peter Del Tredici. Inside back cover: Manchurian catalpa [Catalpa bungei] bears lovely rose-tinted flowers. Photo by Richard Olsen. Back cover: Kevin Conrad photographs a specimen of Viburnum utile near Wudangshan, Hubei, China. He is assisted by a Chinese official who was assigned to help insure safe travel for this 1994 NACPEC expedition. Though never needed for protection, this friendly young man was a great help in collecting seed and herbarium specimens. Photo by Paul Meyer. In This Issue This special issue of Arnoldia honors the upcoming twentieth anniversary of the North America-China Plant Exploration Consortium (NACPEC). Initiated in 1991, NACPEC is a unique organization that has had great success explor- ing and collecting plants within the amazingly diverse flora of China. The collaborative rela- tionship among NACPEC members and with their Chinese colleagues provides an ideal plat- form for extensive collection, distribution, and evaluation of these plants. The Arnold Arboretum is a member of NACPEC — fittingly, given the Arboretum's long history of plant exploration in China. Much has changed in the one-hundred-plus years since E. H. Wilson's China expeditions, though some things — the challenge of bad roads, the spectacular scenery, the thrill of finding rare specimens — remain the same. We hope you enjoy learning more about NACPEC's mission and accomplishments in these pages. The Case for Plant Exploration Peter Del Tredici T he history of plant exploration is as old as human history itself. People have been discovering, collecting, and moving plants for eons, and the process is not likely to stop any time soon. Indeed, it is as ancient as the practice of agriculture itself — it's part of our genetic heritage. The challenge plant collectors face today is how to continue their work without causing further problems for our already badly damaged environment. Despite the best efforts of many research scientists, we have yet to develop a truly reliable way of predicting whether an unknown plant will be problematic without actually growing it under a variety of conditions to see how it behaves. Botanical gardens, with their rel- atively secure perimeters and their commit- ment to science over commerce, are places where new plant introductions can and should be tested for a variety of traits including their potential invasiveness As the world environment continues to deteriorate as a result of human-induced phenomena such as acid rain and climate change, there can be little doubt but that we are going to need tough, adaptable plants for eter Del Tredici inspecting persimmon seeds our managed landscapes more than ever. Many uiing the NACPEC expedition to Wudang Shan, species— including SUch familiar trees as American elm, eastern hemlock, sugar maple, and white and green ash — are no longer planted in our cities because of insect, disease, or stress susceptibility. We have a real need to replace them with stress-tolerant, non-invasive species that can survive all the abuse that people throw at them. Some of these plants of the future may be native to North America, hut I can guarantee you that some of them — either as species or as hybrids — will come from Central and Eastern Asia. And that's where the North America-China Plant Exploration Consor- tium comes in. For the past twenty years this collaborative organization has made it a priority to try to deal with future horticultural problems without creating new ones in the process. The organization is devoted to the collection, propagation, and study of plants in their native habitats, with a potential outcome of selection and eventual introduction. There can be little doubt hut that plant diversity — in all its glorious forms — is going to he crucial in keeping the planet habitable, most especially for humans. Peter Del Tredici is a Senior Research Scientist at the Arnold Arboretum. fU (•* \ The Return to China, Mother of Gardens Paul W. Meyer I n 1929, Ernest Henry Wilson's book China, Mother of Gardens was published, which documented the importance of Chinese plant species to western gardens. Wilson col- lected plants widely in China between 1899 and 1910. Many of his introductions have become important components of the cultivated flora of our gardens and our cities, and have been used widely in plant hybridization and selection. Wilson's China collections greatly expanded our understanding of the Chinese flora as the richest and most diverse flora in the temperate world and identified the usefulness of many species for cultivation. However, until recently, many of the most important and useful Chinese species in Amer- ica were the result of limited seed collections, representing only a narrow slice of the genetic diversity and potential of each species. In some cases, all the plants in this country derived from a single plant or a few seedlings. After multiple generations of propagation from seed, symp- toms of inbreeding were being observed. Since the 1930s, wars and the political situ- ation in China made it difficult, if not impos- sible, for western scientists and plant explorers to travel, study, and collect plants in China. However, Chinese botanists were hard at work during this time, cataloguing, describing, and publishing detailed accounts of their flora. With the gradual opening of China following Presi- dent Nixon's visit in 1972, these publications became more available in western botanical libraries. This new information further docu- mented the richness of the Chinese flora and its potential for further plant exploration, evaluation, and introduction. These data also provided additional information on the natu- ral geographic distribution of species, allow- ing us to target specific areas for collection in particular parts of their range. By doing so, we could potentially maximize adaptability char- acteristics such as winter hardiness, heat and drought tolerance, and adaptability to special soil characteristics. Collaboration Breeds Success Earlier expeditions in South Korea, beginning in the 1960s and 1970s, had clearly demon- strated the diversity of plant species still rela- tively unknown to western horticulture and the importance of studying intraspecific variation and its potential usefulness to landscape crops. Up until this point, collections had been largely one-time efforts and not part of a comprehen- sive plan to collect over a large geographic range. In the early 1980s, Barry Yinger, at that time employed by the United States National Arboretum, proposed a series of Korean collect- ing trips that would facilitate the collection of specific target taxa over separate geographic and climatic ranges. The resulting trips occurred between 1984 and 1989. They were facilitated by the United States National Arboretum in close collaboration with American and Korean botanical institutions and were highly suc- cessful. This collaborative approach based on a multi-year master plan became the model on which we began to build a proposal for a long- range plan for plant exploration in China. Key to the success of the Korean expeditions was the principle of collaboration among insti- tutions as they plan, execute, and follow up on a plant collecting expedition. Most institu- tions today do not have the financial or human resources to do this work alone. Collaboration allows for the division of responsibilities and of the significant financial commitment needed. It also broadens the range of expertise pres- ent in the field. The field work itself is labor Facing page: While on a plant collecting trip for the Arnold Arboretum, E. H. Wilson captured this image of an alpine village (elevation 7,500 feet [2,286 meters]) in the mountains of western Sichuan, China, in August 1908. From the Archives of the Arnold Arboretum. niv ANcnaNv 6 Aruoldia 68/2 (Left to ri"ht} Kris Bachtell, Chris Carley, and Li fianjun collect ash seeds [Fraxinus paxiana NACPEC08-016) on a road in Hong He Gu Forest Park, Shaanxi. intensive and it is important to have multiple hands to physically collect the seeds, make and record the field observations, and complete the evening tasks of cleaning seed and processing herharium specimens. Most important, col- laboration provides multiple sites for propa- gating, growing, and eventually evaluating the collections. Multiple institutions give a variety of testing locales and some level of insurance against seed loss or crop failure. And even if all are successful, it allows for a greater genetic reservoir to he tested and preserved through permanent living collections. Widening the Pool Several notable collection successes from the Korean expeditions encouraged us to continue this work in China. In 1984, there were two expeditions to islands off the northwest coast of South Korea. The key target species was Camel- lia japonica. It was believed that populations on these islands would represent the most cold- hardy forms of the species. Seedlings grown in multiple institutions could he selected for hardiness as well as landscape attributes, and ultimately he used in breeding projects, with the ultimate goal being clones well-adapted and reliably cold hardy in USDA Zone 6 (average annual mini- mum temperature 0 to -lO^F [-17.8 to -23.3"'Cl). Indeed, seed- lings grown have demonstrated superior winter hardiness and, after years of testing, a number of named cultivars have been introduced. Similarly, kousa dogwood [Cornus kousa] was a tried and proven landscape plant but most, if not all, kousa dog- woods in the United States at that time (pre-1980) were descended from a narrow genetic pool. Additional col- lections made in Korea in the 1980s further demonstrated the great variation within that spe- cies. By 1990 we were seeing the promise of greater winter hardiness, increased vigor, and interesting vari- ation in flower bract shape and size from these collections. As we reviewed Chinese floras we discovered that Chinese botanists had observed and documented wide variation within this species in China, so much so that they divided what we know as Cornus kousa into multiple species. The successes of our Korean collec- tions along with the promise of a richness of intraspecific variation encouraged us to pur- sue additional collections of these and other species in China. Another specific plant that motivated us was Chinese hemlock [Tsuga chinensis). During the 1980s and 1990s, hemlock woolly adelgid [Adel- ges tsugae] was becoming widespread in the northeastern United States, causing our native eastern hemlock [Tsuga canadensis] to decline and often die. At both the Morris Arboretum and the Arnold Arboretum, it was noted that a Chinese hemlock growing near an infested eastern hemlock was resisting infestation. A few other Chinese hemlocks growing in other arboreta were visited and also were showing resistance. This led to a comprehensive plan to re-collect Chinese hemlock from a number of different locales across its natural range in Return to China 7 China to further study its adelgid resistance and explore horticultural variation and adapt- abilities within this species. By the late 1980s, travel to China was becom- ing more practical and a group of horticulturists who had worked in Korea began to envision a wide-ranging, long-term plan to collaborate with Chinese colleagues. We had already iden- tified a broad geographic arc across northern China that represented areas with a climate parallel to the northeastern United States. We looked at reported mean temperature in both lanuary and luly and gave priority to areas with both hot summers and cold winters. Also, we continued to target superior Chinese species already known and grown in the United States that might benefit from new collections and the introduction of greater genetic diversity. We also began the slow process (in the days before email) of establishing contacts with Chinese colleagues and exploring the possibility of meet- ing with them in China to map a collaborative plan and agreement. Out of this effort, a loose consortium of institutions came together in 1991 to form The North America-China Plant Exploration Consortium (NACPEC). Founding members included Lawrence Lee of the United States National Arboretum (Washington, D.C.), Peter Bristol of the Holden Arboretum (Kirtland, Ohio), and Paul Meyer of the Morris Arboretum of the University of Pennsylvania (Philadelphia, Pennsylvania). NACPEC, the Early Years Our overtures were enthusiastically received and in the autumn of 1991 the founding Amer- ican nrembers traveled to China to visit a number of botanical and forestry institutions in six cities, and to explore the feasibility of future plant exploration trips. Host Chinese Institutions included the Research Institute of Forestry and Beijing Botanical Garden, the Heilongjiang Academy of Forestry in Harbin, the Chang Chun Forest Botanic Garden, Xian Botanic Garden, and Nanjing Botanic Garden. We visited their herbaria and discussed tar- get species and potential area for collection as well as the nuts and bolts of planning future trips and getting official permissions. With the advice and encouragement of our Ghinese col- leagues, we laid tentative expedition schedules for the next 5 years. As part of the exchange, NACPEC would assist our Chinese partners by supporting Cousa dogwood (Cornus kousa) has a iroad native range and much variation vithin the species. Hemlock wooly adelgids (seen as cottony white dots along the branchlets in this photo) attack native eastern hemlock {Tsuga canadensis) but Chinese hemlock (T. cbinensis) appears to be resistant. RICHARD SCHULHOF 8 Arnoldia 68/2 (From right, facing camera) Peter Bristol, Lawrence Lee, and He Lin examine herbarium specimens in the Nanjing Botanical Garden Herbarium on the 1991 planning trip. Research in the herbarium was helpful in pinpointing potential sites for future exploration. In the far north of Heilongjiang, beautiful remnants of the great Manchurian forest remain. The tallest trees are Pinus koraiensis, Picea jezoensis, and Abies nephrolepis. Common deciduous species include Betula costata, Betula platy- phylla var. mandshurica, Fraxinus mandshurica, Acer pictum ssp. mono, and Quercus mongolica. The Manchurian forest appears quite similar to northern New England forests. research projects, facilitating and supporting student and professional exchanges, and hy procuring wild-collected and cultivated North American germplasm for evaluation hy Chinese institutions. Funding for these expedi- tions was primarily dependent on the participating NACPEC members' institutions with additional support from the National Plant Germplasm System, a part of the Agricul- ture Research Service of the United States Department of Agriculture (USDA). The USDA recognizes that the pro- duction of landscape plants represents a significant and growing part of American agri- cultural production and that, in the past, landscape plants were not well represented in the germplasm repository system. Interest in NACPEC grew following the success of these planning efforts. In 1992, Longwood Gardens (Kennett Square, Pennsylvania) and the Morton Arboretum (Lisle, Illi- nois), based on their expressed interest and experience, were invited to join NACPEC. Later, the Arnold Arboretum (Boston, Massachusetts) and the Uni- versity of British Columbia Botanic Garden (Vancouver, British Columbia) joined the collaboration. Planning progressed for the first NACPEC full plant explo- ration trip to the province of Heilongjiang, located in the far northeastern corner of China. We were hosted by Professor lin Tieshan, a renowned professor of forestry at the Heilongji- ang Academy for Forestry. This first expedition to China was a great learning experience for the American visitors and our hosts alike. We mailed much of our equipment over in advance, including herbarium presses, papers and blot- ters, pole pruners, packing bags, and sphagnum moss for packing and shipping seed. Once we arrived, we had to navigate the protocols of importation of supplies and later the export- ing of seed. As with governments everywhere, these procedures are never fast or easy. We were overwhelmed by the commit- ment and hospitality of our hosts. They did everything possible to help us professionally Return to China 9 (Left to right) Sheng Ning , a local host, and Jeff Lynch collect seeds of Acer triflo- rum, a maple valued for its exfoliating bark and brilliant red-orange fall color. This Chinese man collected a bumper harvest of Korean pine [Pinus koraiensis) cones from the local forest in Jilin. After drying in the sun, the edible seeds (com- monly called pine nuts) are extracted, cleaned, and packed. Korean pine is the most common source of pine nuts in world commerce because they are relatively large, plentiful, and inexpensive. and to look after our safety and human comforts. The modern world had not yet arrived in rural Heilongiiang in 1993 and we had a chance to experience the beauty of the traditional agrarian life in northeast China. In the far north of Heilongjiang, we got to see remnants of the once great Manchurian forest with Korean pines {Pinus koiaien- sis), Yezo spruce [Picea jezoen- sis), and Manchurian fir [Abies nephiolepis] towering well over 100 feet (30.5 meters) tall. By the end of this month- long trip we had collected 112 accessions. Especially notable collections include Maackia amiuensis, a poten- tially useful urban street tree,- Pinus koraiensis, a beautiful and fast growing five-needled pine; and Abies holophylla, one of the firs best adapted to areas with hot summers. Where possible, each acces- sion included dried pressed specimens for herbaria of both Chinese and American institutions and seed lots to be grown and evaluated in our institutions. The herbarium specimens serve as an impor- tant part of the scientific documentation of each germ- plasm collection and a perma- nent record of the occurrence of that species in the wild. This work is especially urgent and important today as China is being developed at an unprecedented pace. Mountainous areas that were largely pristine in the 1980s were being developed with tour- ist resorts and aerial tramways in the 1990s, putting increased pressure on the already lim- ited natural areas in China. The success of this first expedition energized the team to continue planning for two separate expedi- tions in 1994 and others in later years. Since that first diplomatic trip in 1991, NACPEC has sponsored a total of 12 plant collecting trips to China. A World of Opportunities The outcome of this work is hard to fully mea- sure as it has affected so many individuals and institutions in so many ways. Over the years, NACPEC plant explorers have had a chance to Return to China 1 1 visit and study innumerable Chinese plants in their natural habitat and to learn from Chinese colleagues about the plants' economic and folk uses. By seeing a plant growing in its natural habitat, we can glean insights into the growing conditions to which it is best adapted. It has also given our collectors the opportu- nity to lecture to groups of professionals and amateurs about the importance of conserv- ing our planet's plant resources. Addition- ally, NACPEC institutions have hosted many Chinese colleagues and students for study visits and extended internships in the United States over the past 20 years, as part of our broader academic exchanges. Today we are well aware of the dangers of introducing a new invasive species. In many instances we are focused on re-collecting new genetic material of plants that have already proved themselves as well-behaved, handsome landscape plants. When in the field, many poten- tially invasive plants were left uncollected. Warning signs include an aggressive habit in their natural environment or the existence of related species which have already become unruly in the United States. Back at home, curators keep an eye on plants in the botanic gardens and those showing invasive tenden- cies are typically removed. With each trip, NACPEC has become increasingly focused on a limited number of target species that address specific emerging needs, such as resistance to the hemlock woolly adelgid or the emerald ash borer, rather than on general collecting. Over the years, hundreds of plants have been shared with NACPEC members and many other non-member institutions. In all, the database of NACPEC collections lists 1,348 accessions with over 6,000 plants in 9 institutions. Each collector may have their favorites, and individual plants are attracting attention as possible cultivar introductions. But beyond the garden merit of these plants, perhaps one day some "ugly duckling" may be found to contain genes for resistance to some still unknown virulent disease or insect, or may contain a compound effective in the fight against cancer. No doubt the value of these collections will continue to emerge for decades and maybe even centuries to come in ways we cannot yet imagine. NACPEC is probably the most successful, broad-based, and long-lived collaboration of its sort anywhere in the world. And after nearly 20 years of active collecting in its countryside, modern China continues to indeed be the "Mother of Gardens." Bibliography Aiello, A. S. 2005. Evaluating Cornus kousa cold hardiness. American Nurseryman 201(5); 32-39. Aiello, A. S. 2009. Seeking cold-hardy camellias. Arnoldia 67(1): 20-30. Anisko, T. 2006. Plant exploration for Longwood Gardens. Timber Press, Portland, Oregon. Del Tredici, P. and A. Kitajima. 2004. Introduction and Cultivation of Chinese Hemlock {Tsuga chinensis) and Its Resistance to Hemlock Wooly Adelgid, Journal of Arboriculture 30(5): 282-287. Meyer, P. W. 1999. Plant Collecting Expeditions: A Modern Perspective. The Public Garden 14(2): 3-7. Meyer, P. W. 2000 Plant Collecting Expeditions; A Modern Perspective. In: I, R. Ault (ed.) Plant Exploration: Protocols for the Present, Concerns for the Future (Symposium Proceedings). Chicago Botanic Garden, Chicago, Illinois, pp. 7-12. Meyer, P. W. and S. J. Royer. 1998. The North American Plant Collections Consortium. The Public Garden 13(3): 20-23. Meyer, P. W. 1985. Botanical riches from afar. Morris Arboretum Newsletter 14(1): 4-5. Yinger, B. 1989. Plant Trek: In pursuit of a hardy camellia. Flower and Garden 33(2): 104-106. Yinger, B. 1989. Plant Trek: On site with hardy camellias, Sochong Island, Korea. Flower and Garden 33(3); 62-66. Paul W. Meyer is the F. Otto Haas Director of the Morris Arhoretum of the University of Pennsylvania in Philadelphia, Pennsylvania. Facing page: This gateway building is part of the beautiful Taoist temple complex on the slopes of Wudang Mountain in Hubei. Taoist monks find tranquil spirituality in nature. Over the centuries they have helped protect this botani- cally rich forest, duhbed “horticultural heaven" by NACPEC expedition members. Photo by Paul Meyer. Sharing and Enjoying the Joint Botanical Expeditions He Shanan A fter nearly thirty years of isolation from each other, the first modern Sino- American botanical expedition was initiated in 1980, with five American botanists participating in a joint expedition to Shennon- gjia in China's Hubei province. In a reciprocal activity, five Chinese botanists then joined a field expedition in the United States for more than four months in the spring and summer of 1982. It was a historic expedition — the largest Chinese team to make a field trip out- side of China in many years — and it generated a sound mutual understanding and coopera- tive base for the further development of bota- nizing activities. Some ten years later, a series of joint expedi- tions began in China, organized by NACPEC and a group of Chinese botanical gardens, which have continued for twenty years already. Improving on the first Sino-American botaniz- ing trip, the NACPEC expeditions have covered a very wide range of geographical areas and have had teams composed of members from a num- ber of different disciplines. By all accounts, both the American participants and their Chinese botanical garden hosts have been well satisfied by the efficiency, valuable collections, and the mutually beneficial exchanges of science and technology. Speaking as a member of the Chinese botani- cal gardens team, I would like to express my great interest and satisfaction in the project, since it has made a considerable contribution to the ex situ conservation collections in Chinese botanical gardens. First, it increased the acces- sions and enriched the geographical diversity of the botanical gardens' living collections. These collections typically consist of relatively few individuals of a given species, and they are often collected from only a few geographic localities. According to modern concepts of ex situ con- servation, a well-balanced germplasm collec- tion should consist of numerous individuals Professor He Shanan in the propagation house at the Nanjing Botanical Garden. from multiple locations. Second, these kinds of collaborative projects can save both money and human resources by sharing plant materi- als collected with other botanical gardens in different regions, thereby reducing the risk of losing precious plant germplasm. And third, this project provides good opportunities for exchanging scientific information, methodol- ogy, and experience. Personally, I am very interested in know- ing that most botanical gardens in the United States have the same team doing the collecting activities in the wild, managing the propagation Joint Botanical Expeditions 13 Seed from this collection #WD 0A5 grovm as Arnold Arboretum accession t 671-94 Material from Packet Of rM( I ARNOLD ARBORETUM i PLANTS OF THE PEOPLE'S REPUBLIC OF CHINA HUBEI PROVINCE Wudang Shan Emmenopterys henryi Oliv. Tree, 20 m. Ull; b«r1( scaly, brtcU white; fri. green. On rocky ledge, at base of Effacing cliff in moist woodland valley; with Lindera giauca, Actinidia chinensis, Acer ciasifolium asp. henryi. Cornua controveraa, Pueraria lobata, and Quercus glanJutifers; elev. 1200 m. Rare and endangered in the wild. (Same tree as WO-i74) Coordinates: 32*24'27*N. nO*59‘54'E m.. NACPEC94~-Wudang Shan cm. n*. WD-045 c«t.o«u: 18 Sep 1994 -iliilPtT U. S. NATIONAL ARSOBSTUM HCRBABILM. UASHIHCTON, 0. C. Herbarium specimens like this one of Emmenopterys henryi are permanent scientific records of individual collections that may well last long beyond the living material. In most cases, multiple herbarium speci- mens were made of each collection for sharing among the Chinese and American institutions. HARVARD UNIVERSITY HERHARIA ir‘^IKA ItNNlWrS 14 Arnohlio 68/2 Emmenopterys henryi is a rare and endangered tree species native to China. E. H. Wilson first collected this species in 190'' on an expedition for the Arnold Arboretum. He described it as “...one of the most strikingly beautiful trees of the Chinese forests, with its flattish to pyramidate corymbs of pure white, rather large flowers and still larger white bracts.” The 1994 expedition to Wiidang Shan found and collected £. henryi in Hubei (top photo). Some of the seeds from this collection went t the Nanjing Botanical Ciarden, and the resulting seedlings are seen growing in the NBG propagation house (bottom right). herbarium specimen from this collection (previous page) shows the persistent bracts and oblong seed capsules. In cultivatioi F.mmenopterys henryi is notorious for taking decades to start blooming, though this precocious specimen (bottom left) at the Quarryhill Botanical Garden in California bloomed at just six years of age. Joint Botanical Expeditions 15 merican and Chinese expedition members shared information and expertise throughout the collection process. in the garden, and taking care of the resulting collections. Such a unified approach encourages botanical garden staff to have strong feelings of attachment to the collections. In Chinese botanical gardens, sometimes these three activities were conducted by different groups of people; for example, the taxonomists and their technicians conducted the expeditions in the wild, and the horticulturists and gardeners propagated the plants and maintained the intro- , duced materials. It is also helpful for Chinese f botanical gardens to learn to emphasize and to standardize the record system both in the wild and in the garden. Summarizing the achievements of the coop- erative projects, it is obviously very positive, especially as we know that there are so many new plants released. More investigations and more collections are critically important as the planet faces the serious challenge of climate change and ex situ conservation becomes the only effective method for saving plants in the face of relentless urban expan- sion. I would like to suggest that the NACPEC project should continue its development and move ahead with follow-up research on the plants already collected. Conserve more plants for humanity! Have great success in the future! He Shanan was Director of the Nanjing Botanical Garden in Nanjing, China, from 1983 to 1998. PETER DLL TREDICl TRAVELING IN CHINA Clockwise from upper left: S haring narrow rural roads with large logging true led to plenty of white-knuckle moments in China (top two photos). A close encounter on the road to Changbai Shan in 1997 turned nearly fatal — by a matter of inches-^ when an oncoming truck swerved, directing an unsecured log straight toward the NACPEC expei tion van. The end of the log neatly peeled off the driver's door like the lid on a sardine tin (above and at left). Paul Meyer, looking slightly stunned, observes the damage. Ever the plantsmen, the expedition members identi- fied the offending log as Manchurian linden {Tilit mandshurica). Upper left photo Paul Meyer, all others Peter Del Tredici Traveling in China Photo Features 1 7 O ther travel hazards included muddy roads and various waterways as well as sinkholes and road construction (top two photos). Clockwise from right: This apple vendor used a low-tech but efficient means of transport, a wooden handcart. Once at the collection sites, foot power became the required mode of travel. Charles Tubesing leads the expedition members through a patch of Opiopanax elatus. The rewards of hiking included incredible views of the scenery such as Tianchi (Heavenly) Lake at 2,000 meters (about 6500 feet) elevation in the Changbai Shan. Unfortunately, NACPEC expedi- tion members did not see the mysterious monsters that local legend says inhabit this volcanic crater lake. iC9* t * \ FIELD COLLECTING C ollecting seeds, plants, and herbarium specimens is a team effort on expeditions. Clockwise from upper left: Jeff Lynch and Paul Meyer check out an unknown elm species [Ulmus sp. on a hill above the Yalu River, which divides China from North Korea (seen in the background). Though woody plants dominate among NACPEC collections, some her- baceous plants such as Paeonia obovata (held by Sheng Ning) have also been collected. This peony grows in moist, fertile soils in the woodland understory. The glamorous work of plant explorers includes picking up Manchurian ash {Fraxinus mandshurica) seeds along a roadside. Out on a limb: Mr. Park, "the barefoot guide," balances precariously whil collecting branches from a three-flowered maple {Acer triflorum). Chris Carley, Bai Genlu, and Li Jianjun strip seeds from harvested branches of Acer stachyophyllum ssp. betulifolium. Photos clockwise from upper left: Peter Del Tredici, Paul Meyer, Kris Bachtel Peter Del Tredici, Anthony Aiello ■ W.ih i' ■ '■ R ecording detailed data is an essential part of the collection process. Clockwise from upper left: In the mountains of the Beijing area, Rick Lewandowski (left) takes notes on location and surrounding flora while Ned Garvey (center) writes out labels for the seeds being packaged by Charles Tubesing (right). ! Tools of the collecting trade include extendable pole pruners, held here by Wang Xianli. ' Pole pruners are put to use collecting Fraxinus insularis in the rain during the 2008 expedition. = A cluster of fruit collected from Farges filbert [Corylus fargesii). A thin-shelled nut is held within each tightly wrapped involucre. This species was previously rare in the United States and is a valued addition to the USDA's Corylus germplasm collection. Upper right photo Peter Del Tredici, all others Kris Bachtell (Continues on page 36) By the Numbers: Twenty Years of NACPEC Collections Anthony S. Aiello and Michael S. Dosmann B eginning with the initial feasibility expe- dition in 1991, NACPEC has conducted a total of 12 botanical expeditions to China (Table 1). These represent a concerted effort to systematically investigate and explore varying climatic areas, habitats, and ecosystems across a wide geographic range. Although quite com- parable in land mass, China has much greater plant diversity than the United States. Target areas for NACPEC expeditions were deter- mined based on climate information and cover a broad arc from central China where the Qinling mountain range forms the continental divide separating north and south China (the Yellow and Yangtze River systems), through the moun- tain ranges west of Beijing, to the far north and northeast of the country in the provinces bor- dering Russia and North Korea. Although there is a fascinating and diverse flora in Sichuan and Yunnan, these provinces have not been primary targets because plants from this warmer region of China have not performed particularly well in the climates of most NACPEC members. The goals of each NACPEC trip have varied — on many trips we collected broadly, working from a large list of target plants, while on other trips we focused on specific taxa (e.g., Tsuga in 1998 and 1999, and Fraxiims in 2008). (See map on page 26 for locations covered on each trip.) The contributions from these trips have resulted in a wealth of knowledge about the characteristics and ecology of Chinese plants, represented by copious collection notes and herbarium specimens. And, by bringing germ- plasm back to North America and integrating it into the living collections spread among all of the members of the consortium, we collectively learn how these individuals respond under cul- tivation to our diverse growing conditions. The expeditions are summarized in separate trip reports that are housed in the libraries of the participating institutions and generally consist of two parts: a trip journal and the field notes. The journal recounts the daily activities of the trip and also sets out the context for the vari- ous plant collections. The detailed field notes provide extensive information on all of the collections for an expedition. These trip reports provide a resource for current and future explo- ration efforts. Sifting the Statistics As more NACPEC collections were propa- gated, distributed, and evaluated, it became clear that we should report on the results of the NACPEC expeditions. Our goal with this article is to provide information on the suc- cesses and challenges of collecting in this modern era, and to evaluate the significance Detailed notes are taken for each collection. Here, Paul Meyer records a collection location from a GPS (global positioning system) device. jnrise in Xia Ban Si (Cloud Sea), Shaanxi. The photograph was made at an elevation of over 9,000 feet (2,743 meters), the highest tint reached on the 2008 expedition. Photo by Anthony Aiello. of NACPEC collections to botany, plant con- servation, and ornamental horticulture. A similar case study was published by Dosmann and Del Tredici in their review (2003) of the 1980 Sino-American Botanical Expedition (SABE), another collaborative trip that yielded abundant herbarium and germplasm collec- tions from Hubei. We wanted to know if there were any similarities or differences between the SABE and the NACPEC trips, and if there were lessons learned that could be applied not only to future collecting trips, but to living collections management in general. NACPEC members regularly combine and update lists of their expedition holdings into a complete plant survey, and this was most recently completed in late 2009 (for online access to this information see the Data Base of Asian Plants in Cultivation [DAPC] http:// www.quarryhillbg.org, the BG-Base Multi-Site Search page http://www.bg-base.com, and the individual institutions' websites). This combi- ned inventory aids curatorial decisions among the collaborating institutions, helps to find missing or unusual collections, and focuses future collecting efforts. We used this combi- ned inventory as the basis for the descriptive statistics provided in this article. These sta- tistics include all of the collections made on the 12 NACPEC expeditions, as well as seeds collected in 1994, 1997, and 2001 by Professor Cui Tiecheng (formerly of the Xi'an Botanic Garden), and a few sets of seeds received as exchanges. Living germplasm data came from the NACPEC institutions, plus the holdings at the Dawes Arboretum. A very recent inclusion in this survey is the University of Idaho Arbo- retum and Botanical Garden, which received a seed distribution following the 1993 Heilong- jiang and 1994 Beijing expeditions (see page 24). NACPEC: Who We Are and What We Do SINCE its inception, NACPEC's efforts have been motivated by a number of goals, including: Broadening the genetic pool of species already in cultivation, with particular emphasis on extending cold hardiness and increasing vigor, improving adaptability to stressful environments, and increasing insect and disease resistance. Conserving rare species. • Selecting improved ornamental forms. Evaluating and introducing appropriate new species. Increasing our understanding of botanical diversity throughout China. Collaborating with key institutions in the national and international botanical community. NACPEC consists of eight member institutions plus partner organizations that contribute to the success of our collecting efforts and the wide distribu- tion of valuable germplasm. Each location not only has unique growing condi- tions that are favorable for certain types of taxa or those from specific parts of China, but the individual missions and collections policies of each institution are novel. Such diversity is truly an asset. The NACPEC members are: • The Arnold Arboretum of Harvard University, Boston, MA • The Holden Arboretum, Kirtland, OH • Longwood Gardens, Kennett Square, PA The Morris Arboretum of the University of Pennsylvania, Philadelphia, PA The Morton Arboretum, Lisle, IL United States National Arboretum, Washington, DC University of British Columbia Botanical Garden, Vancouver, BC USDA Woody Landscape Plant Germ- plasm Repository, Beltsville, MD Viburnum betulifolium Other partners in these efforts include the Dawes Arboretum in Newark, OH as well as several Chinese botanical institutions listed in Table 1. Twenty Years of NACPEC Collections 23 What's a Collection? V I S I T O R S to public gardens may associate the word "collection" with groups of living plants, often labeled with signs such as "Maple Collection" or "Conifer Collection." But on NACPEC expedi- tions, we use the word collection in a different way. A collection results from one specific act of collecting and may comprise one or more products. Each NACPEC collection receives a unique alpha-numeric code for identification. For example, on the 2005 trip to Gansu we collected seeds from a Cercidiphyllum japonicum and also collected herbarium specimens from the tree. A single collection number, NACPEC05-059, was assigned to both the seeds and herbarium specimens, and any associated data also carry that collection number. Once a NACPEC collection (in the form of seeds, cuttings, plants, or herbarium specimens) arrives at a botanical garden or arboretum, it is typically assig- ned an accession number unique to that institution. The Cercidiphyllum collected in Gansu is accession AA # 126-2007 at the Arnold Arboretum and MOAR # 2005-192 at the Morris Arboretum, but both institu- tions can track their accessions back to the original NACPEC collection, which makes ongoing evaluation and reporting easier and more accurate. Any institu- tion that receives clonally propagated plants of that NACPEC collection in the future may give it their own accession number but will also retain the original NACPEC collection number in their records. This Cercidiphyllum japonicum growing at the Arnold Arboretum is identified by the Arnold Arboretum accession nnmber 126-2007-A (letters identify individual specimens within the accession group), but the label information also includes the original NACPEC collection number, NACPEC05-059. There have been a total of 1,350 unique NACPEC collections since 1991 (Table 2). Of these, 71% (961 collections) are represented by herbarium specimens and 93% (1,250 collec- tions) were originally collected as germplasm (primarily seeds but occasionally seedlings or cuttings); most collections comprised both germplasm and herbarium vouchers. Of the 1,250 germplasm collections made, more than half (56%) are currently represented by living plants among the various member gardens, a percentage somewhat greater than the 1980 SABE (258 of initial 621, or 41 %). Certainly, as in the 1980 SABE, an inability to successfully propagate some germplasm coll- ections led to their initial failure. For example. in the case of some taxa such as Acer (maples), seeds collected may be empty and therefore not viable. Similarly, seeds of other taxa may ger- minate but only grow into weak plants that do not make it out of the propagation/production phase. And there are also those taxa that make it out onto the grounds only to perform poorly and eventually die. Thus, a "success rate" of around 50% is not uncommon. In directly com- paring the NACPEC and SABE collections, we wondered what the contributing factors might be for the slightly higher rate among NACPEC collections (56% versus 41%). Certainly, some of the more recent NACPEC collections are still going through the pivotal propagation/pro- duction phase, which contributes to the higher PAUI. WARNICK UNIVEKSI I Y OI- IDAI lO A number of NACPEC collection plants grow on the vine arbor at the University of Idaho Arboretum and Botanical Garden, including, Clematis mandshurica HLI-0'^3 and Vitis amurensis BI(J-03b, top, and Actinidia arfiuta BICI-025 (male flowers), bottom. Got NACPEC Plants? WHILE writing this article, we happened upon infor- mation that added significantly to our inventory and the compilation of our statistics. Charles Tubesing, curator at the Holden Arboretum, forwarded to me a newsletter from the University of Idaho Arboretum and Botanical Garden. In that newsletter, Paul Warnick wrote about the development of an arbor to hold vines that they had grown from seeds collected by NACPEC. In further correspondence with Paul, I learned that their institution holds 246 NACPEC plants representing 55 taxa and 64 collections. These include 5 collections that previously existed at only one institution, 3 col- lections that previously existed as a single plant at a lone institution, and 2 collections that we previously thought were dead altogether. While we knew that NACPEC collections had been distributed far and wide, this one instance illustrated just how pivotal distributions outside the NACPEC network can be. In light of this information, we would be very interested in hearing if any other organizations have NACPEC collections in their gardens. If so, please contact Anthony Aiello at aiello@upenn.edu . We would be happy to include your records in future NACPEC inventories. — ASA success rate. However, we believe that the overwhelming reason for the grea- ter success is due to the unique nature of NACPEC; wide initial distribution of germplasm — and continuing distri- bution of surplus plants and vegetative propagules — to a network of gardens and arboreta with unique growing environments. Eighty |2000) described several barriers to successful expedi- tions, one of them being the "too-rapid rate of entry' of plants into the system" that then overwhelms staff and faci- lities. Because of its distributive and collaborative nature, NACPEC may have found a way to break this harrier. Notable Successes There are some remarkable success stories from the trips of the early 1990s, with 62% of the 1993 Heilongii- ang collections and 69% of the 1994 Beijing expedition plants still alive today. What might have contributed to these successes’ Germplasm from these trips was widely distributed to numerous NACPEC institutions, and by and large it was well-adapted to these varying climates. And even though the 1999 trip to Sichuan has a fairly low percentage of living germ- plasm (40%), significant collections resulted from this expedition, most notably Tsuga chinensis var. oblin- gisquamata (Table 3). Another important statistic revealed in our assessment is the level of dupli- cation among collections. Of those unique germplasm collections that are currently alive, approximately 60% grow in at least two different institu- tions. This duplication insures against the loss of valuable material and also provides opportunities for broader eva- luation and study across a number of different growing sites. The numbers do not always tell the whole story, however. For example, there are only 15 living collections (out of an initial 30) from the 1995 Collaborative distribution of seed and plant collections helps prevent indivi- dual N'ACPEC member institutions from reaching "propagation overload." Chimonanthus praecox (the cultivar ‘Grandiflorus’ is seen here) bears fragrant yellow flowers in late winter or early spring. 26 Arnoldia 68/2 O Heilongjiang Jilin Inner Mongolia A.R. Liaoning Qinghai ’s Ningxia,'' s ( — Gansu €> Q Shaanxi ooo Henan Jiangstj Hubei Anhui e © Sichuan J Chongqin^^ ' Zhejiang'' Hunan Jiangxi Guizhou J "t^SHANGHAI Fujian ■ Yunnan Guangxi Zhuang Guangdong A.R. >C' Hainan >^^009 Kong SAR. 250 500 1,000 Kilometers l‘ I ‘ I ‘ | I l‘ I ‘ I ‘ ' 125 250 500 Miles NACPEC EXPEDITION LOCATIONS o 1993 Heilongjiang Q 1996 Shaanxi and Gansu O 1999 Sichuan o 1994 Beijing (Qinling Mountains) O 2002 Shanxi o 1994 Hubei ^ 1997 Jilin (Changbai Shan) 0 2005 Gansu o 1995 Shaanxi 1998 Anhui, Guangxi, and Jiangxi 2008 Shaanxi Twenty Years of NACPEC Collections T1 Shaanxi expedition. One of these is Chimonan- thus piaecox (SHX033), a shrub noteworthy for its fragrant flowers in early spring. This plant is well known horticulturally, but as far as we can determine, this is the only wild-collected collection in North America. It is represented by only five plants at the Morris Arboretum and is an example of a collection growing at only one institution. This type of collection, held at only one ins- titution, illustrates one of the challenges facing NACPEC as well as others engaged in germ- plasm acquisition. Forty percent of the NAC- PEC collections grow in just a single place. Even though most of these exist as multiple plants (as in the Chimonanthus], they are potentially at risk and need to be prioritized for distribu- tion. But at even greater risk are those collec- tions that exist as just a single plant in a single institution. For the NACPEC collections, 15% fall into this category. While they are clearly the most tenuous collections and the highest targets for propagation and distribution, this is considerably lower than the 45% of single-plant collections surviving from the SABE. Again, the unique collaborative and distributive nature of NACPEC contributes to this lower number. The annual inventory of combined holdings is the first step in alerting NACPEC members of the rarity of their own holdings. A PRIME example in the category of a single plant is Magnolia biondii (QLG062A) collected in 1996 in the Foping Nature preserve in Shaanxi. This rare magnolia is a close relative of Magnolia stellata and is growing as a single individual at the Morris Arboretum. In light of its high conservation value and its rarity in cultivation, it becomes a very important target for propagation and distribution to other botanic gardens. 'lese photographs show the distinctive long carpel (in center of flower) and long fruit structure with red-ariled seeds of Magnolia hndii specimens growing at the Arboretum Wespelaar in Belgium. I PHILIPPE DE SPOELBERCH 28 Arnohiia 68/2 In contrast to these sparsely represented taxa, there are a num- her of collectittns that are widely held among the NACPEC members. There are 13 collections grown in at least seven institutions, making them ideal candidates for further evaluation for broad adaptability as well as uniformity. Topping this list is Acer pictuin ssp. mono BJG141, held by nine institutions, followed by Acer davidii ssp. gross- er! (RIG017) and Corylus fargesii (QLG23 1 ), each held at eight gardens. It is difficult to know why some plants are grown more successfully and widely compared to others, hut factors include initial quantities, broad original distribution, seed viability, curatorial interest, and broad adaptability to an array of growing conditions. In combined NACPEC holdings, Acer is the most frequently coll- ected genus — not surprising given that China is the center of diver- sity for maples, with 99 of the 129 species worldwide occurring there. Keen member interest in Acer (five of the NACPEC members and part- ners — the Arnold, Dawes, Morris, and Morton Arboreta, and UBC Botanic Garden — are members of the North American Plant Collec- tions Consortium's multi-site Acer collection), combined with the great natural diversity has led to the extensive holdings in this genus. There have been 106 distinct collections of maple, representing 33 taxa. Of these, 73 (10% of all living NACPEC collections) are represen- ted by living germplasm for a total 29 taxa and 585 plants among all of the member institu- tions. Among these are garden-worthy plants such as Acer davidii (including ssp. grosser!), A. pictum ssp. mono, and A. trifloruni; plants rarely grown in North American botanic gardens sucb A. ceriferum and A. sterculaceum ssp. frcincbetti [A. tsinglingense); and plants of high conservation value, including A. A large specimen of Acer pictuin ssp. mono growing in Heilongjiang. griseum, A. miyabei ssp. miaotaiense, and A. yui. These collections represent a signifi- cant increase in the diversity of maples coll- ectively held not only by NACPEC members, but among other North American institutions due to redistribution. After Acer, other frequently collected taxa include Viburnum (20 taxa), Quercus and Euonymus (15 each), and Rhododendron (13). Of special significance are the 26 total collec- tions representing 1 1 taxa of Fraxinus. Some of these ash taxa, such as f. insularis and F. pper left, Rick Lewandowski measures the diameter of 1 impressively large specimen of paperbark maple {Acer iseum)} upper right, Acer ceriferum growing in the wild in liina; lower, A cultivated specimen of three-flowered maple cer triflorum). paxiana, may eventually hold the key to sol- I ving the emerald ash horer epidemic that is i devastating native and planted populations of ‘ North American ash species, i Tsuga is another genus that stands out among ! the collections, not because of the diversity of I taxa hut for the numher of collections made, i Representing a classic case of a genetic hott- I leneck, T. chinensis had been introduced as a j single individual into the United States in 1910. j Starting in the 1990s, Tsuga chinensis became I a prime target for NACPEC collecting expe- ditions because of the immediate threat to North American hemlocks by hemlock wooly ; adelgid [Adelges tsugae]. A total of 33 collec- Chinese hemlock (Tsuga chinensis) in its native habitat. Photo by Kris Bachtell. tions of the adelgid-resistant T. chinensis and its varieties were made from across its native range, 19 of which are represented hy living plants (Table 3). The original collections — mostly hy seed hut in some cases as seedlings or even cuttings — were made from several pro- vinces from southeast China through the nor- thwestern limit of its range in southern Gansu. Of the 1 8 seed collections, 1 7 are represented hy at least one plant; none of the cuttings and few of the seedling collections are extant. Because of their high priority, these plants have been widely distributed among the NACPEC mem- bers and show that targeted collecting (instead of broad, opportunistic collecting) can greatly increase the diversity of germplasm among our collective holdings. These plants have been widely distributed among other North Ameri- can botanic gardens, aiding in research on and wider introduction of Chinese hemlock. What Have We Learned? After nearly 20 years of collecting germplasm and herbarium specimens, we can draw a num- ber of important conclusions. Overall these statistics point out the importance of collabo- ration in sustaining the NACPEC collections. Without the combined efforts of the member organizations, it is difficult to imagine how these expeditions would have occurred, let alone how the plants would have been sub- sequently propagated and maintained over a period of time. In total the herbarium speci- mens and living collections represent material of horticultural, botanical, and conservation significance. The sum of the consortium work is certainly greater than its individual parts, leading to significant scientific contribution and a deeper understanding of the Chinese flora as well as its horticultural potential. This is an important point to emphasize — NACPEC's goals arc broader than simply introducing garden- worthy plants. First and foremost is the primary scientific documentation of botanical diversity. Additional lessons learned include the need for sustained and repeated collecting within varied geographic, climatic, and ecological ran- ges, and the importance of vision and long-term planning. Looking forward, this analysis will prove a useful tool as we focus on additional Table 1. List of NACPEC expeditions, abbreviations, participants and dates. Trip Name Abbreviation Participants Dates 1991 Initial Feasibility Expe- dition (Beijing, Heilongjiang, filin, Shaanxi, Jiangsu) LL Bristol, Peter; Holden Arboretum Lee, Lawrence; U.S. National Arboretum Meyer, Paul; Morris Arboretum 10 Oct -2 Nov 1991 1993 Expedition to Heilongjiang HLJ Bachtell, Kris; Morton Arboretum Bristol, Peter; Holden Arboretum Meyer, Paul; Morris Arboretum Gao Shi Xin; Heilongjiang Academy of Forestry Jin Tae Shan; Heilongjiang Academy of Forestry Liu Jun; Heilongjiang Academy of Forestry 25 Aug -28 Sep 1993 1994 Expedition to Beijing BJG Bachtell, Kris; ; Morton Arboretum Lewandowski, Rick; Morris Arboretum Garvey, Edward; U.S. National Arboretum Tubesing, Charles; Holden Arboretum Liu Mingwang; Beijing Botanical Garden IBCAS 13 Sep - 3 Oct 1994 1994 Expedition to Hubei WD Conrad, Kevin; U.S. National Arboretum Del Tredici, Peter; Arnold Arboretum Meyer, Paul W.; Morris Arboretum Thomas, R. William; Longwood Gardens Hao Riming; Nanjing Botanic Garden Mao Cailaing; Nanjing Botanic Garden 6 Sep - 11 Oct 1994 1995 Expedition to Shaanxi SHX Garvey, Edward; U.S. National Arboretum Lewandowski, Rick; Morris Arboretum Cui Tiecheng; Xi'an Botanic Garden 31 Mar - 17 Apr 1995 [996 Expedition to Shaanxi & 3ansu (Qinling Mountains) QLG Ault, James; Longwood Gardens Conrad, Kevin; U.S. National Arboretum Lewandowski, Rick; Morris Arboretum Kim Kunso; Norfolk Botanical Gardens Cui Tiecheng; Xi’an Botanic Garden 30 Aug - 18 Oct 1996 (1997 Expedition to Zhangb^ Shan (Jilin) NACPEC97 (CBS) Bachtell, Kris; Morton Arboretum Del Tredici, Peter; Arnold Arboretum Lynch, Jeffrey; Longwood Gardens Meyer, Paul W.; Morris Arboretum Tubesing, Charles; Holden Arboretum Wang Xian Li; Shenyang Institute of Applied Ecology Cao Wei; Shenyang Institute of Applied Ecology Sheng Ning; Nanjing Botanical Garden 25 Aug - 27 Sep 1997 .998 Expedition to L & SE. China (Anhui, Juangxi, Jiangxi) NACPEC98 (TS98) Lewandowski, Rick; Morris Arboretum Garvey, Edward; U.S. National Arboretum Li Weilin; Nanjing Botanical Garden Wang Qing; Nanjing Botanical Garden 5 Oct -22 Oct 1998 999 Expedition to Sichuan NACPEC99 (TS99) Belt, Shawn; U.S. National Arboretum Garvey, Edward; U.S. National Arboretum Stites, Jerry; Longwood Gardens Wang Qing; Nanjing Botanical Garden 1 Oct -20 1999 [002 Expedition to Shanxi NACPEC02 Aiello, Anthony; Morris Arboretum Bachtell, Kris; Morton Arboretum Bordelon, Carole; U.S. National Arboretum Bristol, Peter; Holden Arboretum (Chicago Botanic Garden) Tang Yudan; Beijing Botanical Garden IBCAS 9-30 Sep 2002 005 Expedition to Gansu 1 1 NACPEC05 Aiello, Anthony; Morris Arboretum Bachtell, Kris; Morton Arboretum Scanlon, Martin; U.S. National Arboretum Wang Kang; Beijing Botanical Garden Sun Xue-gang; Forestry College of Gansu Agricultural University 14 Sep - 12 Oct 2005 1 008 Expedition to Shaanxi NACPEC08 Aiello, Anthony; Morris Arboretum Bachtell, Kris; Morton Arboretum Carley, Chris; U.S. National Arboretum Wang Kang; Beijing Botanical Garden 16 Sep - 8 Oct 2008 NANCY ROSE Acer davidii is much admired fur its striped bark. This specimen at the Arnold Arboretum (AA#666-94-A) was grown from seed collected during the 1994 expedition to Hubei (NACPEC collection #\VD 0401. Table 2. Collections totals for formal NACPEC expeditions and other associated collections. Trip abbreviations follow Table 1. TRIP Year Total Herbarium collections # % Germplasm # % Living germplasm # % Exists at only one institution* # % Exists as a single plant" # % LL 1991 25 0 0 24 96 9 38 5 56 3 33 HLG 1993 112 96 86 102 91 63 62 20 32 5 8 BJG 1994 144 130 90 138 96 95 69 26 27 11 12 WD 1994 194 149 77 171 88 83 49 40 48 21 25 SHX 1995 33 0 0 30 91 15 50 11 73 5 33 QLG 1996 263 235 89 234 89 120 51 48 40 22 18 NACPEC 97 1997 143 122 85 139 97 91 65 22 24 7 8 TS 98 1998 42 0 0 42 100 19 45 17 89 11 58 TS 99 1999 33 29 88 27 82 11 41 6 55 1 9 NACPEC 2002 2002 78 71 91 71 91 48 68 20 42 2 4 ' NACPEC 2005 2005 90 85 94 85 94 60 71 29 48 4 7 I NACPEC 2008 2008 51 44 86 45 88 43 96 20 47 4 9 Expedition total 1208 961 79 1108 91 657 59 264 40 96 15 Other*" 142 0 0 142 100 47 33 36 77 15 32 I Grand Total 1350 961 71 1250 93 706 56 294 42 109 15 * A germplasm collection that exists at only one institution; may be of one or multiple plants ** A germplasm collection that is represented by a lone plant at one institution ’"Include collections made during tourist visits, as well as those collections made through contract er pseudosieboldianum is another garden-worthy small maple collected on several of the NACPEC expeditions. 34 Arnoldiii 6H/2 Bai Genlu (back to camera), Wang Kang (white hat), Li )ianjun, and Anthony Aiello examine Acer caesium ssp. giraldii (NACPEC08-014) in Hong He Gu Forest Park, Shaanxi. collecting efforts, and will allow us to focus our efforts on propagating and distributing plants of horticultural, botanical, and conser- vation significance. Lastly, and perhaps most importantly, we acknowledge the cultural exchange that has occurred among the American and Chinese institutions and the individuals involved. Without these lasting relationships none of these expeditions or the resultant collections would have occurred. The end result is a mutual affinity and deep appreciation for the relationships that have ensued. Bibliography Aiello, A.S. 2006. Plant collecting on the eaves of the world. The Plantsman .6 (4): 220-22.S. Anisko, T. 2006. Plant exploration for Longwood Gardens. Timber Press, Portland, Oregon. Del Tredici, P., P. Meyer, R. Hao, C. Mao, K. Conrad, and R. W. Thomas. Plant Collecting on W'udang Shan. Arnoldia 55(1): 12-20. Dosmann, M. and P. Del Tredici. 2004. Plant Introduction, Distribution, and Survival: A Case Study of the 1980 Sino-American Botanical Expedition. BioScience 33 (6): 588-597. Eighty, R.W. 2000. An assessment of ornamental plant introduction in the not-for-profit sector. In: I. R. Ault (ed.) Plant Exploration: Protocols for the Present. Concerns for the Future (Symposium Proceedings). Chicago Botanic Garden, Chicago, Illinois, pp. 14-22. Meyer, P. W. 1999. Plant Collecting Expeditions: A Modern Perspective. The Public Garden 14 (2): 3-7, Anthony S. Aiello is the Gayle E. Maloney Director of Horticulture and Curator at the Morris Arboretum of the University of Pennsylvania, and Michael Dosmann is Curator of Living Collections at the Arnold Arboretum. Table 3. List of NACPEC Tsuga collections. Taxon Coll.# How Material Province of Collection Number of Total plants was Collected origin alive? Institutions among all growing this institutions collection Tsuga chinensis Cui 97-053 Seed Shaanxi yes 4 24 Cui 97-054 Seed Shaanxi yes 4 26 NACPEC05022 Seed Gansu yes 3 12 NACPEC05063 Seed Gansu yes 4 12 QLG013 Seed Shaanxi yes 3 7 QLG188 Seed Shaanxi yes 6 20 QLG190 Seed Shaanxi yes 7 18 QLG193 Seed Shaanxi yes 6 23 QLG216 Seed Shaanxi yes 2 9 QLG217 Seed Shaanxi yes 3 17 SHX017 Seedling Shaanxi yes 1 1 XBG s.n. Seed Shaanxi yes 1 5 Subtotal 12 12 living 174 (100%) Tsuga chinensis var. TS 99-018 Seed Sichuan yes 4 22 oblongisquamata TS 99-022 Seed Sichuan yes 5 11 TS 99-025 Seed Sichuan yes 2 22 TS 99-026 Seed Sichuan yes 3 9 TS 99-027 Seed Sichuan yes 4 9 TS 99-033 Seed Sichuan no 0 0 Subtotal 6 5 living 73 (83.3%) Tsuga chinensis var. TS 98-046F Seedling Jiangxi yes 1 2 tchekiangensis TS 98-058B Seed Guangxi yes 1 1 TS 98-035E Seedling Jiangxi no 0 0 TS 98-036E Seedling Jiangxi no 0 0 TS 98-040H Seedling Jiangxi no 0 0 TS 98-042C Seedling Jiangxi no 0 0 TS 98-043E Seedling Jiangxi no 0 0 TS 98-044F Seedling Jiangxi no 0 0 TS 98-051B Seedling Guangxi no 0 0 TS 98-051C Cuttings Guangxi no 0 0 TS 98-052B Seedling Guangxi no 0 0 TS 98-062B Seedling Guangxi no 0 0 TS 98-066B Seedling Guangxi no 0 0 TS 98-066C Cuttings Guangxi no 0 0 TS 98-069 Seedling Zhejiang no 0 0 Subtotal 15 2 living 3 (13.3%) Grand Total 33 19 living 250 (57.6%) 36 Arnohiia 6H/2 (Continued from page 19) PROCESSING F reshly collected seeds and herbarium spt mens must be processed promptly to pre vent spoilage. These tasks occupied man evenings for all of the expedition members. Clockwise from upper left: Soft-fleshed fruits are soaked and sieved to remove any pulp before the seeds are dried and packed. Rick Lewandowski cleans seeds at a trough sink during the 1994 expedition to the Beijing region. Pressed herbarium specimens must be drier quickly or else mold may set in. During ij rainy spell, Peter Del Tredici and Mao Cailaing resorted to burning charcoal under the herbarium press to help dry the specimens. Air-drying seeds and herbarium samples. Kris Bachtell and Martin Scanlon begin pro- cessing cones of Tsuga chinensis. Dry fruits like these maple samaras are win nowed, carefully cleaned, and sorted before they are packed in labeled bags. Photos clockwise from upper left: Kris Bachte. Paul Meyer, Peter Del Tredici, Anthony Aiello, Kris Bachtell Traveling in China Photo Features 37 hoD E xpedition members enjoyed many ele- ments of Chinese cuisine on their travels. 'lockwise from upper left: \ vendor at a market in Harbin sells fruit including round Asian pears native to I this region and warty, orange, ripened bitter melons. graduate student Zhang Wei and an expedi- , tion driver, Mr. Liu, eat spicy noodles in a restaurant in Min Xian, Gansu. This noodle vendor in Xi'an served up bowls of piping-hot seasoned noodles, n Shanxi's Pangquangou National Preserve, ' this "mushroom lady" was collecting a type of edible mushroom known to grow i on Populus davidiana. ]^/>otos clockwise from upper left: Paul Meyer, jfns Bachtell, Anthony Aiello, Kris Bachtell GETTING TO KNOW CHINA B eyond collecting plants, the NACPEC expeditions have provided an opportunity for participants to see and learn more about China's people and landscape;) Clockwise from top: Tall, blond expedition members Bill Thomas and Paul Meyer attracted a lot of attention in the streets of Wudang Shan City, Hubei. This Tibetan woman was harvesting Anemone tomentos. plants to feed to her pigs. Chinese colleagues hosted a birthday celebration for Kris Bachtell in September 2005 (left to right: Anthony Aiello, Kris Bachtell, Zhang Zuoshuang, He Shanan, and Zhang Aoluo and his wife). Opposite page, clockwise from upper left: Peter Del Tredici shoots pool with the locals on a street in the Wudang Shan area, Hubei. Children give pig riding a try, to the amusement of onlookers in a small village in the Mo Gou Forest area in Gansu. A misty view of the Seven Sisters, a set of peaks in the Tai Bai Shan reserve in Shaanxi. Photos this page, clockwise from top: Peter Del Tredici, Kris Bachtell, Kang Wang Photos opposite page, clockwise from upper left: Paul Meyer, Kris Bachtell, Anthony Aiello Traveling in China Photo Features 39 Planning Future NACPEC Plant Exploration Challenges and Opportunities Kunso Kim, Kris Bachtell, and Kang Wang T he North America-China Plant Explora- tion Consortium (NACPEC) is an innova- tive partnership formed in 1991 between American and Chinese institutions to organize and conduct plant explorations in China. Since its inception, this collaborative effort .has been successful in collecting many botanically and horticulturally important plants including paperbark maple {Acer griseuni), Farges filbert [Corylus fargesii), and Chinese stewartia {Stew- artia sinensis). During the two decades of its existence, NACPEC has witnessed dramatic changes occurring around the globe that have profoundly affected the consortium's collecting efforts, most notably the Convention on Biolog- ical Diversity, the complexity of ex situ plant conservation, the impacts of climate change, the spread of invasive species, and the tighten- ing of import/export regulations. These issues have challenged us to rethink the way we plan and organize plant explorations as the consor- tium moves forward into the next decade. CURRENT ISSUES AND CHALLENGES Convention on Biological Diversity The Convention on Biological Diversity (CBD) is an international treaty signed at the United Nations Conference on Environment and Development (also called the "Earth Sum- mit") in Rio de Janeiro, Brazil, in 1992. The key component relevant to NACPEC activi- ties is Article 15, Access to Genetic Resources (CBD 1999). This provision endorses the sov- ereign rights of countries over their biological resources. The article not only offers countries an opportunity to revamp their efforts in con- servation of biodiversity and sustainable uses, hut also gives them leverage over their natural resources. In essence, the possibility of con- ducting any plant exploration in China rests upon consent from the host country based on mutually agreed terms. As a consequence, the consortium may see increasing restrictions imposed by the Chinese government on cer- tain collecting areas including national parks and reserves that are often biologically rich. Described in the same article is another provi- sion called "Access and Benefit Sharing" that requires the consortium to establish a clear understanding of how the benefits should he shared. Participating countries are required to share with the host country any benefits arising from commercialization or other utilization of the genetic resources. In the past, NACPEC has made good faith efforts to honor this provision by training Chinese students in plant curation and database management, hosting a number of Chinese scientists during their extended visits to the United States, supporting BG-Base and BG-Map at the Beijing Botanical Garden (IBCAS), supporting field work inside China by a number of Chinese botanists, and by sharing a portion of the royalties from the sale of plants through the Chicagoland Grows® Plant Introduction Program. Ex Situ Plant Conservation Conserving rare species has always been one of the objectives in the consortium's collecting trips (Meyer 2000). Despite the high priority given to horticulturally important plants, the consortium's annual inventory survey includes 52 accessions that are on the current lUCN Red List of Threatened Species. Should future explo- rations emphasize collecting red-listed plants as the major goal; As habitat loss in China con- tinues to increase and more public gardens are responding to the plea to participate in ex situ Facing page top: Farges KIbert (Corylus fargesii), a promising tree species for landscape use, was collected in this river terrace habitat in Gansu. Bottom: A temple within the Lingkongshan Chinese pine (Pinus tabuliformis) national preserve, one of a number of botanically rich national preserves in China. Photos by Kris Bachtell. 42 Arnoldia 6H/2 When human development encntaches on the habitat of threatened plant species, ex situ conservation may be the key to preve in}> species extinction. Here, the "suburbs” of a village in Hubei expand up a steep terraced slope. Photo by Peter Del Tredici. plant conservation, there is an opportunity for the consortium to renew its efforts and play a more active role in acquiring threatened species and sampling species from different populations to get a better representation of genetic diversity. The consortium is uniquely positioned to expand its ex situ conservation role. It has established successful collaborations with Chinese institu- tions, gamed invaluable field experience, and established a high standard of documentation that holds important information for breeding, evalu- ation, and conservation puiqioses (Bachtell 2000). Capitalizing on its experience and collaborations, future explorations can contribute to advancing the goal of preserving 60% of threatened plant species in accessible ex situ collections as laid out in the Global Strategy for Plant Conservation Target 8 (CBD 2005). Future plant exploration with conservation in mind will need to priori- Some widely grown landscape plants of Asian origin have become invasive in parts of North .America. One example is winged euonymus [Euonymus alatm), a popular shrub also known as burning bush because of its bright carmine red fall color. Future NACPEC Plant Exploration 43 tize species by conservation concern and sam- ple multiple populations in order to maximize genetic diversity. When sampling from within populations, care must be taken to collect suf- ' ficient germplasm to maximize the capture of j genetic diversity for long-term seed storage, or ! clonal stands for taxa that have recalcitrant seeds. ! J Introducing Horticulturally Superior Plants This was at the heart of initial NACPEC plant exploration efforts and remains an important goal for the consortium. The definition of a superior plant in the early days of NACPEC plant exploration often meant that a plant - should have increased cold hardiness, tolerance : to stressful conditions (including urban land- \ scapes), and resistance to pests and diseases, j Exciting plants with such traits are in the pro- i cess of being introduced and others are being :■ developed through breeding and selection pro- (! grams utilizing the rich germplasm of plants ij the consortium has assembled. While the above criteria are still valid, bio- logical invasiveness has emerged as an area of concern. The need to screen introduced plants for non-invasive characteristics has become a high priority for the consortium, which has stepped up its efforts by excluding from expedi- tion target taxa lists any potentially invasive species. At the same time, participating gar- dens need to develop vigorous risk assessment protocols to determine the invasive potential of lesser known species from the pool of plants that are maintained in living collections before they reach reproductive stage. Use of reliable predictive modeling to assess invasive risk can allow the consortium to avoid time-consuming screening and expensive processing in the field (Widrlechner 2009). Climate Change Climate change has a huge implication for bio- diversity and consequently on the consortium's future collecting initiatives. Major vegetation 1 44 Arnoldici 68/2 Ginseng requires shade to grow, so the forests are replaced with vast expanses of low shade structures, seen here in the Changbai Shan area. shifts are predicted by various climatic models. Hawkins (2008) states three different possibili- ties: (1) some plants will adapt to new climate conditions through selection or plasticity; (2) some plants will move to higher latitudes or alti- tudes; or (3) other plants may become extinct. It is predicted that continued climate change will ultimately drive many plants to extinction. An average world temperature rise of 2 to 3°C over the next 100 years will result in up to 50% of the 400,000 or so higher plants being threatened with extinction (Hawkins 2008). How should NACPEC's future plant explorations respond to climate change’ Studying climate analogues has provided the most useful information to NACPEC in planning the potential target areas in China. The consortium considers seasonal rainfall, mean seasonal temperatures, and sum- mer high and winter low temperatures to iden- tify the target areas (Meyer 2000). Will it he necessary for NACPEC to reconsider expanding the collecting zones towards warmer regions or lower altitudes and latitudes in response to anticipated vegetation shifts’ Import /Export Regulations NACPEC members who participated in past plant explorations are familiar with the com- plexity of obtaining collecting permits in China. Compliance with rules governing col- Emerald ash borer (Agritus planipennis). Photo by David Cappacrt, Michigan State University, Bugwood.org. I M(I Hi I 1 1ll H 1 1 M Future NACPEC Plant Exploration 45 I e 2008 NACPEC expedition focused on collecting Chinese ash species. This large specimen of Fraxinus insularis grows near a intry house in Shaanxi. Photo by Kris Bachtell. lecting permits and germplasm importation is absolutely necessary, yet it is one of the most cumbersome aspects of any plant exploration. With the CBD recognition of countries' sov- ereign rights over their natural resources, it is possible that the consortium will see more limited issuance of collecting permits and increased restrictions on collecting in special areas. Adding to the challenges, there are new rules on importation of plant germplasm into the United States. Even clean seeds with phyto- sanitary certificates attached do not guarantee an easy entry. Some people mistakenly think that the possession of an import permit issued by USDA APHIS for small lots of seeds means free passage, but it only eliminates the require- ment to obtain a phytosanitary certificate from the exporting country (USDA 2008). In view of recent insect and disease outbreaks such as emerald ash borer [Agrilus planipennis), Asian longhorned beetle [Anoplophora glabripennis], and sudden oak death {Phytophthora ramorum], it is understandable that the USDA is increas- ingly tightening the rules. The threat posed by invasive plant species is another issue that has contributed to stricter importation rules. STRATEGIC PLANNING FOR FUTURE COLLECTING EFFORTS Past plant exploration efforts focused on col- lecting a broad range of species and a large num- ber of accessions. Priority taxa lists are carefully developed during the trip planning process, but inevitably non-target taxa are added to the list 46 Arnoldia 68/2 along the way, resulting in increased collec- tions. This practice of collecting a broad range of species will need to change. The current issues and challenges described above necessi- tate that future plant explorations become more sharply focused. This can he accomplished by the annual survey inventory which examines total living accessions accumulated over the last two decades and shows which institutions hold what accessions. The survey results have helped NACPEC understand gaps in its col- lections and will help with planning future trips. Based on an analysis of past results, a trip could target a single genus or a few gen- era depending on the purpose or priority of the taxa. More focused collecting trips allow the initiation of new research projects in response to rapidly changing environmental conditions such as those posed by invasive species. The 2008 Shaanxi expedition was an example of a goal-driven and therefore more focused collect- ing trip. This USDA-funded trip was specifi- cally for collecting ash [Fraxinus] species that are not well represented in American botanic gardens and arboreta. A percentage of the seeds collected were seed banked within the USDA's National Plant Germplasm System. The result- ing progenies are to be incorporated into a feed- ing preference study to test the ash species' resistance to the emerald ash borer. TOWARDS GREATER COLLABORATION Modern day plant explorers are facing a dif- ferent set of challenges than did earlier plant explorers. The impact of climate change on vegetation is one obvious reason for the con- sortium to take a more active role in conserving plants. The CBD has helped focus our atten- tion on how to balance the needs for access to genetic resources and benefit sharing, with the ultimate goal of conservation of biologi- cal resources through preservation and sustain- able use. In spite of the tremendous success NACPEC has experienced in collecting and introducing plants, there is a need for the con- sortium to focus future plant explorations on collecting a more narrowly defined list of target plants, paying particular attention to prevent- ing accidental introduction of plants with invasive potential. NACPEC has succeeded largely through the close collaborative work between the American and Chinese member institutions. The issues listed above present opportunities for NACPEC to help meet the challenges presented by our changing world. Literature cited: Bachtell, K. 2000. Documenting your collections. In: I. R. Ault (ed.) Plant Exploration: Protocols for the Present, Concerns for the Future (Symposium Proceedings). Chicago Botanic Garden, Chicago, Illinois, pp. 52-57. Convention on Biological Diversity. (2 November, 1999). Article 15. Access to Genetic Resources http://www.cbd.int/convention/articles. shtml!a=cbd-15 Convention on Biological Diversity. (27 luly, 2005). Global Strategy. Target 8. http://www.cbd.int/ gspc/future.shtml#8 Hawkins, B., S. Sharrock, and K. Havens. 2008. Plants and cUmate change: which futurel BGCI, Surrey, UK. Meyer, P. W. 2000 Plant Collecting Expeditions: A Modern Perspective. In: I. R. Ault (ed.) Plant Exploration: Protocols for the Present. Concerns for the Future (Symposium Proceedings). Chicago Botanic Garden, Chicago, Illinois, pp. 7-12. USDA. APHIS: Plant Import. (14 luly, 2008). On small lots of seeds, http://www.aphis.usda.gov/import_ export/plants/plant_imports/smalllots_seed. shtml Widrlechner, M. P., ). R. Thompson, E. I. Kapler, K. Kordecki, P. M. Dixon, G. Gates. 2009. A Test of Four Models to Predict the Risk of Naturalization of Non-native Woody Plants in the Chicago Region, fournal of Environmental Horticulture. 27(4): 241-250. Kunso Kim is Head of Collections and Curator, and Kris Bachtell is Vice President of Collections and Facilities, both at the Morton Arboretum in Lisle, Illinois. Kang Wang is a Research Horticulturist at the Beijing Botanical Garden in Beijing, China. Facing page: A view across the Wudang Mountain range from atop Wudang Mountain in Hubei. The building in the foreground is part of the Taoist monastery and temple complex for which this mountain is famous. Photo by Paul Meyer. I During NACPEC expeditions plant species are targeted for collection for a range of reasons* including environmental adaptabilities, conservation value, and ornamental features. Presented here are thirteen profiles of notable plants collected on these expeditions. Paperbark Maple Acer griseum Paul W. Meyer P aperbark maple is an iconic Chinese spe- cies with beautiful exfoliating cinna- mon-colored bark that never fails to grab attention. It is frequently highlighted in public gardens and connoisseurs' gardens throughout the temperate world. It was first introduced to the United States by E. H. Wilson through the Arnold Arboretum in 1907. In addition to its stunning bark, this species is widely admired for its clean, fine-textured foliage, orange-red fall color, and relatively small stature, usually under 35 feet (10.7 meters) tall. It is believed that until recently, all or most paperbark maples in the United States derived from the genetically narrov/ 1907 Wilson intro- duction — it consisted of only two plants. Some contemporary seedlings lack vigor, a possible sign of inbreeding over the past century. The re-collection of paperbark maple to introduce greater genetic diversity has been a high priority from the very beginning of NACPEC planning. Of the many hundreds of plants I have observed and collected in China, none were more exciting than finding a grove of wild paper- bark maples on Wudang Mountain in Hubei in 1994. Wudang is the site of a famous Taoist temple, and the forests on its slopes have been relatively well protected. On September 21st, 1994, the Hubei expedition team was especially excited to find a scattering of paperbark maples in the understory of a rich, diverse forest at an elevation of 836 meters (2743 feet). It was one of the most biologically diverse habitats that any of us had ever experienced. Dubbed "horticulture heaven" by the collectors, we found many choice species including Stewartia sinensis, Cornus kousa, Cornus controversa. Ilex pernyi, and many others growing naturally on this mountainside. The paperbark maples growing on Wudang Mountain were relatively small, growing on a west-facing slope in thin, rocky soil. Being in the understory, most were leggy and the foliage was high off the ground. With careful observa- tion though, we spotted the winged samaras | in the upper canopy. Using pole pruners, we ] were able to collect herbarium specimens and j a small seed sample. \ The following year, in April 1995, NACPEC team members Rick Eewandowski, Teicheng Cui, and Ned Garvey spotted an incredible ; specimen of paperbark maple in the Baxiam Forest Station in Shaanxi, less than 200 kilo- meters (124 miles) west of Wudang Mountain. They spotted the tree from afar; its leaves had not yet emerged, and they were struck by a distinct warm orange glow reflecting from the tree's bark. The collectors wrote in their jour- nal, "Holy Hannah! We encountered the biggest ■ specimen we ever saw of Acer griseum. This was incredible... We can't describe the impact of the bark color and the massive stem — the effect was overwhelming." This tree measured 81.4 , centimeters (32 inches) in diameter at 3 meters (9.8 feet) above the ground. It was estimated to^ be about 27 meters (88.6 feet) tall. Though nof collections of living germplasm resulted, the^ herbarium specimens, descriptions, and photo- graphic documentation of this individual tree have redefined our thinking about the potential* of this species. Paperbark maple is known to frequently pro-^ duce empty samaras with no viable seeds. That I was the case with the Hubei collections. After) cutting open many samaras, we found a few (less; than 5 percent) with seemingly viable seeds.' Fortunately, there were also small seedlings growing under the trees, some of which were Acer griseum 49 PAUL MEYER SO Arnoldia 68/2 Paperbark maple is noted for its beautiful bark and red-orange autumn foliage color. carefully dug bare-root, stripped of their senesc- ing leaves, and packed in moist sphagnum moss. The seeds never germinated, hut these dormant seedlings were brought home successfully and 13 are growing at NACPEC institutions. Though this lack of viability is frustrating to a propagator, the upside is that this species has little potential of becoming invasive. I live on the grounds of the Morris Arboretum and two of the Wudang Mountain paperbark maples are growing in my garden. One is an especially fine specimen. It is a very vigorous individual and in its youth it grew more than 1 meter (3.3 feet) a year. Today it stands over 8 meters (26.2 feet) tall and has a diameter of 27 centimeters (10.6 inches) measured 30 centime- ters (1 1.8 inches) from the ground, iust below the first branch. Perhaps because of its strong growth, its hark is especially beautiful, with heavy exfoliation. Morris Arboretum propagator Shelly Dil- lard took cuttings of this tree in 1998, 1999, 2000, and 2001 while the tree was still juvenile. None rooted successfully. In 2001, I rooted a low branch of the tree in my garden hy layer- ing, resulting in the only successful propagation of this individual. This layered plant has the same vigorous habit as its parent, and in luly 2010 it had a 6.2 centimeter (2.4 inches) diam- eter measured 30 centimeters (11.8 inches) from the ground and stood about 3.5 meters (11.5 feet) tall. Four other individuals of this Hubei accession are growing at the Morris Arboretum and each year we watch them, hoping that one might produce some fertile seed for growing on and further evaluation. Biblioj'raphy Del Treclici, Peter. 2007. The Paperbark Maple— One Hundred Years Later. Arnoldia 65(2); 40. Del Tredici et al. 1995. Plant Collecting on Wudang Shan. Arnoldia 12-20. Paul W. Meyer is the F. Otto Haas Director of the Morris Arboretum of the University of Pennsylvania in Philadelphia, Pennsylvania. Beautybush Kolkwitzia amabilis Michael Dosmann I t was in the late summer of 1901, while exploring the mountains northwest of Ichang, Hubei, China, that Ernest Henry Wil- son encountered a shrub which would become one of his favorite introductions: Kolkwitzia amabilis. At the time, he wasn't even quite sure what it was — his notes for collection #1007 simply state that the unnamed plant was 5 feet (1.5 meters) tall, had been free-flowering, with possibly red blooms, and had spinose fruits. The seeds were sent to Veitch Nursery in England where they germinated and grew. In November 1907, plants (labeled as Abelia sp.) were sent to the Arnold Arboretum — the species' first intro- duction to North America. Shrubs (now under the correct moniker Kolk- witzia] flowered at the Arboretum for the first time in June 1915. Their early-summer displays of pink blossoms, profusely borne on arching branches, so impressed Wilson and others that it was christened beautybush. Thereafter, in early to mid June, the Arboretum's Bulletin of Popular Information routinely included a glowing snippet about the blooming Kol- Beautybush bears a profusion of pink blossoms in early suninier. MICHAEL DOSMANN PETER DEL TREDICl 52 Arnold id 68/2 Kevin Conrad stands next to a visually unimpressive but botanically important specimen of beautybush, which was collected from during the 1994 Hubei trip. kwitzia, how big they were getting, and which specimen in the Arboretum was faring best. In fact, the species' merits were lauded to such an extent that in 1927 Wilson noted that the original plant on Bussey Hill had "been much mutilated for propagation purposes, and from it, either hy seeds or cuttings, has originated the whole stock of this plant in America." Not everybody agreed with Wilson's endorse- ment, however, with some even suggesting that plants were not as gorgeous in flower as claimed, or that the plants didn't flower at all. His dander up, Wilson sought to set the record straight on several occasions. His statement on lune 7, 1930, (a few months before his untimely death) sums it up: "There is a foolish rumor abroad that this plant when raised from seed does not blossom. The story is ridiculous since the original plants were raised from seed and the particular plant on Bussey Hill Road is also a seedling... Another canard in circulation is that It is an acid-loving plant. As a matter of fact, it will do equally well on a moderately acid soil or on limestone." Nobody could doubt his love for the plant, for in the same passage he states "Among the deciduous-leaved shrubs that central and western China has given to American gardens Kolkwitzia stands in the front rank." Amazingly, it was not until September 25, 1994, that this beautiful and elusive species was collected again, about 100 miles north of Wilson's original collection site in Hubei. The participants on the NACPEC expedition to Wudang Shan discovered multiple plants on a hillside near Yan Chi He, and collected ample seed (collector number WD 122). The germinated seedlings at the Arnold Arboretum grew vigorously, and within 18 months were about 0.5 meter (1.6 feet) tall. Unfortunately, all of these plants were sold by mistake at the Arboretum's plant sale in 1997. This was a striking loss, but fortunately seeds of this col- lection were grown at other institutions also. In the spirit and interest of sharing material, the Arnold Arboretum received cuttings from 3 plants at the Morris Arboretum in 2008. They have rooted and will eventually be planted out. Almost everything we know about this spe- cies in cultivation can be traced to Wilson's sin- gle introduction event, so we are curious to see how this new collection compares to the origi- nal germplasm. No formal studies or evalua- tions have taken place so far, hut there are some preliminary observations that are worth further investigation. Phenological data from the Mor- ton Arboretum from the past 8 years show that the Wilson material on average reaches peak bloom about 1 week earlier than the Wudang Shan material. Perhaps only a minor difference, hut this is worth further study. If it holds true, it would he worth selecting for later blooming in self-pollinated FI and F2 generations of the Wudang Shan germplasm. Michael Dosmann is Curator of Living Collections at the Arnold Arhoretum. Henry's Viburnum Viburnum henryi Carole Bordelon V iburnum henryi, com- monly known as Henry's viburnum, was discov- ered by Augustine Henry and introduced to the west by E. H. Wilson in 1901. Native to central China, V. henryi is rela- tively rare in cultivation in the United States, existing primar- ily in public gardens. When this plant was discovered during the fall 1996 NACPEC expedition to the Qinling Mountains in China's Shaanxi province, the team of collectors considered this find a high point of their trip. They were impressed by its beautiful dark green foliage and its large clusters of glossy red fruit. The seeds were col- lected and propagated for tri- aling, and fourteen years later, V. henryi is still an impressive plant growing at the United States National Arboretum and the Morris Arboretum. Henry's viburnum is an evergreen shrub, typically growing 7 to 15 feet (2.1 to 4.6 meters) tall, and is hardy in USDA Zones 7 to 10 (average annual minimum temperature 0 to 40°E [-17.7 to 4.4°C]). Its growth habit is lax, especially when young, but its spread- ing, arching branches can be pruned into a small upright tree, if desired. Otherwise, little aesthetic pruning is required (any pruning should be done after flowering). The attractive foliage and flowers of Henry’s viburnum. DANIIL MOSQUIN, UBC BOTANICAL GARDEN DANIEL MOS' "JIN, UBC BOTANICAL 1 iARDE \ 54 Arnohlia ('>H!2 Henry's vibiirniiin bears fruit that turns from red to blaek in late summer. It has an iipri};ht, open growth habit. This handsome plant has year-round orna- mental interest as well. In the spring months, the new foliage emerges with a bronzy cast that matures to a glossy dark green, which is held throughout the growing season. The narrow, 2 to 5 inch (5 to 13 centimeters) long leaves are serrated above the middle of the leaf and may sport attractive red petioles. During the fall, the leaves may take on a purplish-red hue — depending on sun exposure — that persists into winter. During winter, the grayish brown bark is revealed. V. henryi blooms in June, display- ing slightly fragrant white flowers that occur in panicles that are 2 to 4 inches (5 to 10 centime- ters) tall and wide. The flowers are attractive to both bees and butterflies. In luly, terminal clusters of glossy red fruit appear, covering the entire plant. As the summer wanes, the red fruit matures to black. Henry's viburnum grows best m full sun or part shade and prefers a well-drained, slightly acid, moist soil. It is not a heavy feeder, but it can be fertilized in late winter and after flow- ering. Applying a mulch such as composted leaves reduces the need for supplemental water- ing and fertilizer. No disease or insect problems causing substantial damage to the plant have been noted. The ideal propagation method is by semi-hardwood cuttings some time between late May and late lune. Propagation by seed is also possible, but requires at least one cycle of warm/cold stratification and may take up to several years to germinate. Viburnum henryi is easy to grow and fits into a variety of landscapes. It is recommended for gardens in the southeastern and northwestern sections of the United States but, since it has also performed well in the Washington, D.C., area, it is worth testing in protected sites in Zone 6 areas. Henry's viburnum makes a wor- thy addition to gardens and may be a more common sight in the future. Carole Bordelon is Supervisory Horticulturist, Gardens Unit, at the United States National Arboretum in Washington, District of Columhia. Paul W. Meyer Manchurian Fir Abies holophylla F irs are among the most beautiful of land- scape conifers. However, since firs are mainly native to cool northern areas or ■ high elevations, many of them do not grow well south of New York City or in regions where : summers can he very hot. The Manchurian fir, Abies holophylla, is among the most heat tol- erant firs and has proven itself well adapted to midwest and mid-Atlantic states. It is also one of the most handsome firs, with distinctive : bright green foliage color and a wide-spread- ing horizontal branching pattern with age (it is more pyramidal in youth). In addition to its heat tolerance, it is exceptionally winter hardy, capable of withstanding temperatures to -30°F (-34°C). In nature, the Manchurian fir grows not only in the mountains but also at lower elevations i and in valleys where it is exposed to hot sum- j mer temperatures. Its range includes North i and South Korea, northeastern China, and far southeastern Russia. It often grows in associa- ■ tion with Korean pine [Pinus koraiensis], Mon- ; golian oak {Quercus mongolica], purplebloom ! (or Korean) maple {Acer pseudosieboldianum), : and three-flowered maple {A. triflorum). It is ■ among the tallest trees in the forest canopy, i often exceeding 100 feet (30.5 meters). In China ‘ its wood is valued for use in construction and furniture, though it is not considered as high quality as the wood of Pinus koraiensis. In the northeastern United States, with the decline of eastern hemlock [Tsuga canadensis] '■ and the overuse of white pine {Pinus strobus) ■ and Norway spruce {Picea abies), we have a ■ need for a greater diversity of attractive, well- I adapted conifers. Since it was first introduced in 1905, Manchurian fir has proven itself to be a useful, non-invasive, and adaptable landscape plant. But unfortunately it is still little known The growth habit and foliage of Manchurian fir. PAUL MEYER PAUL MEYER 56 Arnoldia 6H!2 This tall specimen of Manchurian fir was photojiraphed in South Korea, part of its native range. outside of arboreta and botanic gardens. Until recently tbe germplasm represented in this country was narrow, not fully representing the species' geographic range in its natural habitats. Through the work of collaborative expeditions to Korea in the 1980s hy institutions that later formed NACPEC, followed hy the 1993 and 1997 NACPEC expeditions to Hielongjiang and Iilin Provinces, the genetic representation in North America has been expanded. Seedlings grown from accessions collected in Korea in 1981 are thriving and are now over 25 feet (7.6 meters) tall and 22 feet (6.7 meters) across at the ground. Seedlings from other accessions collected in China in 1993 are just hitting their stride, now standing 4 feet (1.2 meters) tall. At the Morris Arboretum, seeds were treated with cold stratification for 60 days at 41 F (5°C) before sow- ing. The seeds then generally germinated reliably within a few weeks. We have found that the seedlings are very slow growing for the first few years, but as they get established can grow over 18 inches (45.7 cen- timeters) a year. Several specimens of Abies holophylla have been grow- ing well at the Morris Arbore- tum since before 1933. These mature specimens are over 70 feet (21.3 meters) tall and have taken on a distinctive broad- spreading horizontal habit. A prized specimen at the Mor- ton Arboretum in Lisle, Illi- nois, was planted in 1939 and is considered one of their best firs. Curator Kunso Kim reports young plants from the NACPEC expeditions are also performing well at the Morton Arboretum. He observes that the Manchurian fir is relatively shade tolerant, although plants have a more open habit in the shade. Heavy elay or poorly drained soils can he problematic for firs, so planting on higher, well-drained sites is recommended. Landseape-sized Manchurian firs are difficult to find in nurseries, hut small plants are some- times listed by specialty mail order nurseries. A diligent and patient colleetor will certainly he rewarded with a fine growing specimen. Paul W. Meyer is the F. Otto Haas Director of the Morris Arboretum of the University of Pennsylvania in Philadelphia, Pennsylvania. Qinling N\ap\e, Acer tsinglingense; or Franchet's maple, Acer sterculiaceum subsp. franchetii Douglas Justice C hina serves up an enor- mous variety of plants for our gardens and landscapes, so much so that the plant explorer Ernest Henry "Chinese" Wilson famously called China "the mother of gardens." One need only think of the numbers of cultivated Viburnum, Rhododendron, and Magnolia species that hail from China to get an idea of the mag- nitude of temperate plant diver- sity there. While impressive in number, many Chinese species are too tender for cultivation in much of North America. So when a "new" cold-hardy Chinese maple comes along, it is cause for gardeners to sit up and take note. Such is the case with a maple collected in the Qinling (Tsingling) Moun- tains of Gansu Province during the 1996 NACPEC trip: the Qingling maple [Acer tsinglin- gense] — or Franchet's maple [Acer sterculiaceum subsp. franchetii) as it's being called in North America. Qinling maple is native to the mountains of Shaanxi, Henan, and Gansu provinces in north central China at eleva- tions of 1200 to 1500 meters (3940 to 4920 feet). This area of China is an important bio- By either name, this maple may be a promising addition to North American landscapes, diversity hot spot, with many endemic plant and animal species. Two parallel mountain ranges — the Qinling and the Daha — trend east-west, dividing the moist, subtropical to warm temperate south and the drier, cold temperate north. The northern boundary is defined by the Qinling Mountains, where tem- peratures are considerably cooler than in the southern Daba Mountains at the same eleva- tion. According to the collection notes from the 1996 expedition, this species was found grow- DOUGLAS JUSTICE mUC.LAS lUSTICt 58 Arnnldici 68/2 Autumn foliage color of Qinling (or Franchet’s) maple. ing on a steep stream bank alongside a variety of familiar temperate plants including Carpi- nus (hornbeam), Maliis (crabapple), and Cornus (dogwood), a good indication that it should be relatively cold hardy. Franchet's maple is found to the southwest of the Qinling Mountains but there is some dehate about whether the two species are truly separable. North American botanists generally consider them the same species; however, dis- tinctions have been noted among some indi- vidual specimens growing in cultivation. The question is, are the distinctions clear enough to warrant a split (as recommended in Flora of China)l According to the Flora of China account, A. tsinglingense displays three-lohed leaves with wide-spreading side lobes, while the leaves of A. sterculiaceum subsp. franchetii are of a thicker texture and have forward-pointing lobes. The young branches of Qinling maple are described as light brown (vs. darker for Franchet's), and the inflorescences, individual flowers, and samaras are smaller in Qinling maple. In gardens, A. tsinglingense appears to be a robust, medium-sized maple with a strong branch structure that produces an upright-spreading crown. Leaves have a papery tex- ture and turn beautiful shades of apricot and red m autumn. It is worth noting that cultivated plants of A. tsin- glingense — specimens at the United States National Arboretum and the Mor- ris Arboretum — have often been described as hand- some or attractive, while those of Franchet's maple are widely dismissed as dull or coarse. Most European accounts list A. sterculiaceum subsp. franchetii as having little ornamental value, and plants at the University of British Columbia Botanical Garden grown from older seed collections made in Hubei and Sichuan Provinces (to the south and west of the Qinling collections) could also easily be described in this disapproving light. Qn the other hand, the response of maples to the cli- mate in eastern North America is often man- ifested in neater, more compact growth and autumn leaves with more saturated colors. This could explain much of the difference, but until a wider sample — representing trees from the Qinling and beyond — are grown under the same conditions, these questions will go unan- swered. Whether we are seeing a minor variant of Franchet's maple or a bona fide species in Qin- ling maple is an open question. More research is required to settle the science, but judging by the plants in gardens, this fine-looking maple appears worthy of wider cultivation, at least in eastern North America. Douglas (ustice is Associate Director and Curator of Collections at the University of British Columbia Botanical Garden in Vancouver, British Columbia. Chinese Stewartia Stewartia sinensis Peter Del Tredici ”"n perusing my handwritten jour- nal from the 1994 NACPEC trip to Wudang Shan in Hubei Province, China, I found the following entries regarding the Chinese stewartia, Stew- artia sinensis: Monday, September 19, 1994: "The other highlight [besides finding Acer griseum] was to see Stewartia sinensis — the biggest plant I've seen of any Stewartia — about 30 inches p6 centimeters] in diameter at the base and 50 feet [15 meters] tall, with a clear bole for the first 20 to 30 feet ]6 to 9 meters]. The bark was a buff tan color — carried high up into the crown — and abso- lutely smooth with little or no flaking. Certainly the most magnificent tree I saw on Wudang Shan. It should also be noted that a spot right next to the Stewartia. above it to be precise, was selected as a site for a public toilet — and it was disgust- ing to the point that no one but me dared to go near the tree. Perhaps that is the secret to its vigor.” This young specimen of Chinese stewartia displays multi-colored bark Tuesday, September 20, 1994: 'Up the mountain again, then a quick turn to the east at about 1300 meters [4,265 feet[ and off into the woods. It was misty and rainy the whole day, giving the whole place a great air of mystery ... The rain and hea\w fog limited our visibility pretty much to what was immediately beside the path — but there was so much. .After about an hour or so on the path, we came upon an incredible house nestled under the cliffs. It looked like it had been there forever — no one was around so I took a few pictures. It really felt like the same China that Wilson saw. A little ways beyond the house and garden we came to a bend in the road where it looped back into a ravine. Our guide, Mr. Zeng, a collector of medicinal plants among other things, pointed out a beautiful specimen of Stew- artia sinensis, and then we saw another both with the beautiful, rich, smooth, ciimamon-red bark — a wonder to behold and to touch! Cornus kousa was there too, and a small i4 inch [10 cen- timeter] diameter’ specimen oi Acer griseum. All within the narrow space of ten square meters — I felt as though I'd died and gone to horticultural heaven. The only thing missing, sadly, was seeds on any of the plants. The conditions were moist and shady and steep, with an oak overstor>'. " It was in this location — Hubei Horticultural Heaven we called it — that 1 noticed a small Stewartia seedling, about 20 centimeters (8 inches tall with a distinct kink at its base, growing along the edge of the path. 1 imme- diately stopped and dug it up while the other PETER DEL TREDICI 60 Arnoldio 68/2 Chinese stewartia blooms in midsummer. A mature specimen in Cliina shows smooth, sandstone-colored bark. members of the party went on ahead. At the end of the expedition, the plant was washed clean of soil and packed in moist sphagnum moss for shipment back to the United States. The plant passed inspection at the USDA inspec- tion station at Beltsville, Maryland, and, after 48 days on the road, arrived at the Arnold Arboretum on Novem- ber 7, 1994. It was immediately pot- i ted up, assigned the accession number ' 691-94, and left to overwinter in a cool greenhouse. The seedling was moved to the out- j door nursery in spring 1996, and it grew to a height of 1.1 meters (3.6 feet) by the end of luly. In spring 2000, it was moved I from the nursery to the grounds, where i it has proved to be completely hardy. . By the end of the 2009 growing season, | the plant was 4.7 meters (15.4 feet) tall ! and 4. 1 meters ( 13.5 feet) wide with two | co-dominant trunks arising from the ' stout base which is 14 centimeters (5.5 i inches) in diameter. The plant flowered , for the first time in the summer of 2002 and has gone on to flower every year i since. The flowers, which are produced from the end of lune through mid luly, ’ are 6 to 7 centimeters (2.4 to 2.8 inches) ; across with heautiful light lemon yel- i low anther filaments and short pedi- ! cels, indicating that it is S. sinensis var. ! sinensis according to the Flora of China. ! In Boston, the new leaves emerge in , early May and are distinctly hairy and : tinged with red anthocyanin pigment; both features disappear within a week ; or so. The hark is cinnamon-red where it ; is not exfoliating and olive-green where \ the hark has peeled off in fine, papery I flakes. Over time. I'm sure the tree will develop mature hark that is "smooth as | alabaster and the colour of weathered j sandstone" (to quote W. J. Bean), like ' the magnificent specimen we saw on i Wudang Shan. Peter Del Tredici is a .Senior Research Scientist at the Arnold Arboretum. Chinese Chinquapin Castanea henryi Sandra L. Anagnostakis C harles Sprague Sargent wrote a beautiful description of this chestnut tree in his Plantae Wilsonianae in 1917. He also revised the taxonomy to the name that we still use today. Here is an excerpt from his article: E. H. Wilson made this photograph of a large Castanea henryi growing in Hubei Sheng, China, on June 22, 1910. "This very distinct species is distrib- uted from the neighborhood of Ningpo through the valley of the Yangtsze River as far west as Mt. Omei. On the mountains of western Hupeh and of eastern Szech'uan it is common in woods. This chestnut grows to a larger size than any other Chinese species and trees from 20 to 25 meters [66 to 82 feet] tall with trunks from 1 to 3 meters [3.3 to 9.8 feet] are common. Occasionally trees 30 meters [98.4 feet] tall and 5 meters [16.4 feet] in girth of trunk are met with. The leaves are green on both surfaces and entirely glabrous except for a few appressed hairs on the underside of the primary and secondary veins. The leaves are without lepidote glands except on the upper surface of the very young leaves, from which they disappear very early. Although variable in size the leaves are very eharacteristic; they are always eaudate- aeuminate and broadest below or at the middle, and the secondary veins are projected in long aristate points. The shoots are dark-colored and quite glabrous and the winter-buds are brownish, short, broadly ovoid, obtuse or subaeute and are glabrous or nearly so. The styles vary in number from 6 to 9, and the fruit may he solitary or two or three on a short spike. The spines of the ripe involucre are sparsely villose. All the fruits we have seen contain a solitary nut, but it is prob- able that oecasionally two occur, as they do in the Ameriean C. pumila . " My interest in this species was piqued when I saw a large planting of it at Callaway Gardens in Hamilton, Georgia. Founder Cason J. Cal- laway was very interested in chestnuts, and in 1935 he began planting chestnut trees from Asia procured by the United States Department of Agriculture's plant exploration and impor- tation program. Over a period of eight years, he planted 2,192 chestnuts, and among them were 202 Castanea henryi from eight differ- ent locations in China. I visited the chestnut plantings at Callaway Gardens in 1993 with Dr. Jerry Payne and Ann Amis from the USDA. We noticed that most of the chestnuts were badly damaged by the Asian chestnut gall wasp that Dr. Payne had discovered and described in 1976, shortly after a chestnut grower acciden- tally brought it to central Georgia. Within one AKCI llVtS OF THE ARNOLD ARBORETUM PAUL MEYER PAUL MEYER 62 A mold id 68/2 This Morris Arboretum specimen of Castanea henryi (\VD-069) was Srown from seed collected in VVudans Shan on the 1994 Hubei expedition. It flowers heavily and bears sweet-tasting nuts that are quickly devoured by squirrels, deer, and other w ildlife. Oeveloping nuts are enclosed in prickly involucres. C. henryi, and all plants that wc saw of this species had either very few or no galls. Finding a chestnut species that was clearly resistant to gall wasp presented an opportunity to breed resistance into our orchard and timber chestnut lines (C. henryi is also resistant to chestnut blight). We have one mature C. henryi here at the Connecticut Agricultural Experiment Station, but others planted over the years have not been winter- hardy enough to survive. Seeds that Wilson collected were planted at the Arnold Arboretum, but no trees from this accession (AA-551) now survive. ■However, one open-pollinated offspring (a probable cross with a nearby Chinese chestnut, C. mollissirna] is still alive and well ( AA-623-32). Since that discovery of gall wasp resistance in Georgia, I have been including C. henryi in my crosses to produce better timber and nut-produc- ing chestnut trees for our northeast- ern forests and orchards. We don't know what pest or disease of chestnuts will next be brought into the United States, but it is clear that imported chestnut species will he called into use in hybrid- ization to combat these new threats. All the more reason to say "Keep exploring, NACPEC!" References: Payne, I. A., R. A. Green, and C. D. Lester, 1976. New' nut pest: an Oriental chestnut gall wasp m North America. Annual Report of the Northern Nut Growers Association. 67: 83-86. Sargent, C. S. 1917. Plantae Wilsonianae: An enumeration of the woody plants collected in western China for the Arnold Arboretum of Harvard University during’ the years 1907. 1908. and 1910 by E. H. Wilson. Volume 3, p. 197. Cambridge, Massachusetts: University Press. of the plantings we came to a block of what I thought were lapanese chestnuts (C. crenata] and noticed that there were no galls. A check of the planting plan revealed that these were Sandra L. Anagnostakis is a research scientist in plant pathology and ecology at the Connecticut Agricultural Experiment Station in New Haven, Connecticut. Epimediums Epimedium spp. Carole Bordelon Epimedium stellulatum bears starry white flowers. A lthough the vast majority of the plants targeted for col- lecting by NACPEC are trees and shrubs, several genera of herba- ceous plants have been targeted as well. Since China is the major area for the diversity of epimediums {Epimedium spp.), it made perfect sense to target this group of adapt- able perennials. Thirteen accessions of epimedium were collected during NACPEC trips, several of which are highly ornamental and should be recognized as worthy plants for the shade garden. In the fall of 1994, members of the NACPEC expedition to the Wudang Shan mountain range located in central China (which is famous for its exceptionally rich and diverse flora) collected several notewor- thy accessions of epimedium. This was a historically significant trip as there were many new species of epi- medium being described in China at the same time. With the help of Darrell Probst, an expert in the col- lection, identification, and intro- duction of epimediums, those 1994 Wudang Shan epimedium accessions were correctly identified and, more importantly, several of them proved Epimedium lishihchenii has long-spurred yellow flowers, to he new species not represented in the NACPEC members' institutional holdings. Epimedium lishihchenii and Epimedium stel- lulatum are just two of the species identified from that trip. Epimedium lishihchenii is an attractive plant hardy to at least USDA Zone 4 (average annual minimum temperature -20 to -30°E [-28.9 to -34.4°C]). It has a running habit and reaches 12 inches (30.5 centimeters) in height. The large evergreen leaflets are leathery and sustain little damage in the winter months. It has bright yel- low flowers with elongated spurs, and blooms in late April or early May. Although the flowers are attractive, this plant's best quality is the CAROLE BORDELON CAROl E RORimON CAROLE BORDELON 64 Ann)hlia 68/2 foliage. It remains fairly clean throughout the growing season. In the winter, the foliage may he tinged with an attractive burgundy color. Like Epimedium lishihchenii, Epimedium stellulatum is an evergreen species hardy to Zone 4. It has a clumping hahit and is smaller in stature than Epimedium lishihchenii. E. stel- lulatum blooms early in the season, revealing small white starlike flowers that are held above the leaves on erect stems. Though it is consid- ered to he evergreen, it has sustained more win- ter damage to the foliage at the United States National Arboretum than Epimedium lishi- hchenii. During the 1996 NACPEC expedition to the Quinling Mountains, several additional accessions of Epimedium stellulatum were col- lected. These additional accessions have leaf- lets that are slightly larger and narrower than the 1994 Epimedium stellulatum collection. The epimediums that hail from China occur primarily in woodlands in temperate hilly or montane regions. Keeping this in mind, they do best in moderately cool and half shady con- ditions. They thrive best in a moist but well drained soil and will tolerate periods of drought provided their roots are not exposed. They ben- efit from being mulched with leaf mold. Epime- diums are best propagated by division. Epimediums make excellent landscape plants because they can grow in a variety of situations and are easy to care for. Depending on the spe- cies, they thrive in sun or full shade and can provide year-round interest in gardens. Carole Bordelon is Supervisory Horticulturist, Gardens Unit, at the United States National Arboretum in Washington, District of Columbia. Glossy, leathery foliage is an ornamental feature of Epimedium lishihchenii. Chinese Hemlock Tsuga chinesis Peter Del Tredici O ne of the most impor- tant of all NACPEC collections is the Chi- nese hemlock [Tsuga chinen- ; sis). Prior to 1979, this species i appears to have been success- fully introduced into North : America only once — a single i seedling collected hy E. H. Wil- i son in Hubei, China, in 1910 that is still alive today. This ! accession has been frequently i propagated and widely distrib- i uted by the Arnold Arboretum. I The lack of Chinese hemlock I diversity became a significant factor when horticulturists i began to notice that the spe- j cies was highly resistant to the Japanese strain of hemlock 1 woolly adelgid (HWA) that was I ravaging native stands of east- j ern hemlock [Tsuga canaden- sis) throughout the central and ! southern portion of its range in I eastern North America, j Working through its various i Chinese contacts, NACPEC ! began a concerted effort to acquire Chinese hemlock I germplasm in order to facili- i tate research on its growth I rate, habitat tolerances, and I resistance to HWA. The collec- i tions began in 1994 with seeds ! provided by the Xian Botani- i cal Garden and peaked in 1996 j with 6 separate collections from various habitats in the Qinling Mountains in Shaanxi Province, the northern part of A specimen of Tsuga chinensis var. tchekiangensis growing in Jiangxi. i PETER i:'£LTR, DICI 66 Arnoldia ('>Hi2 Tsiiga chinensis growing in montane habitat its range. In all, some 33 different collections of three different varieties of the species were made. Representatives from 19 of these collec- tions — totaling some 250 plants — are growing at various NACPEC gardens. The largest of them is at the Morris Arhoretum and has reached 4.9 meters (16 feet) in height with DRH (diameter at breast height) of 9 centimeters (3.5 inches) after 10 years of growth. True to initial reports, Chinese hemlock has so far proved completely resistant to HWA in a wide variety of North American locations. It is fully cold hardy into USDA Zone 5 (average annual minimum tem- perature -10 to -20 F [-23.3 to -28.9°C|) and is relatively fast growing — the mean height of 38 seedlings growing under variable conditions on Hemlock Hill at the Arnold Arboretum was 169 centimeters (66.5 inches) at 10 years of age. 1 observed Chinese hemlock at the Arnold Arhoretum during the 2009 growing season and noted that the species both began growing and stopped growing about two weeks earlier than eastern hemlock. Interestingly, the new growth on vigorous terminal shoots was the same for both species — about 45 centimeters (17.3 inches) — which was the greatest among the seven hemlock species measured. Compared to eastern hemlock, Chinese hemlock is a bit Tsuga chinesis 67 v’htly drooping branch habit on a young Chinese hemlock. Attractive foliage of Chinese hemlock. "droopier" during the growing season, seems to be comparably shade tolerant (although this trait has not actually been quantified), is less cold hardy — Zone 5 versus Zone 3 (aver- age annual minimum temperature -30 to -40°F [-34.4 to -40°C]) — and, as mentioned, has the great advantage of adelgid resistance. It is a ter- rific plant for replacing adelgid-killed eastern hemlocks under cultivated conditions. References i Del Tredici, P. and A. Kitajima. 2004. Introduction , and cultivation of Chinese hemlock [Tsuga chinensis] and its resistance to hemlock woolly adelgid [Adelges tsugae). Journal of Arboriculture 30(5): 282-287. Bentz, S. E., L. G. H. Riedel, M. R. Pooler, and A. M. Townsend. 2002. Hybridization and self- compatibility in controlled pollinations of eastern North American and Asian hemlock (Tsuga) species. Journal of Arboriculture 28(4): 200-205. Hooper, B. K., R. M. Bates, J. C. Sellmer, and G. A. Hoover. 2009. Challenging Chinese hemlock [Tsuga chinensis} with hemlock woolly adelgid [Adelges tsugae] ovisacs. Arboriculture and Urban Forestry 35[1]: 1-4. Peter Del Tredici is a Senior Research Scientist at the Arnold Arboretum. Amur Maackia Maackia amurensis Paul W. Meyer O ne of our most important plant exploration goals is eollecting tree species that demonstrate stress tolerance and are therefore likely candidates for evalu- ation as urban street trees. Maackia amurensis is out- standing in its promise as a tough and useful urban tree. It is native over a wide geographic area including Japan, the Korean penin- sula, northeast China, and far eastern Russia. It is a member of the legume family (Fahaceae) and it is one of the relatively few trees that support nitrogen fixing bacteria on its roots. Although it was introduced to the United States in the late nineteenth century, it is still relatively rare here. In cultivation Maackia amurensis is a medium- sized tree reaching 45 feet (13.7 meters) or more (we were surprised to see specimens in China grow- ing well up into the for- est canopy, taller than the species is usually reported to grow). It has compound leaves similar to its rela- tive, black locust [Rob- inia pseudoacacia]. As the leaves emerge in the spring they are covered with silky hairs which give the tree a silvery-gray appearance. Maackia amuiensis 69 [ s Amur maackia in China managed to survive in difficult soil conditions t h highly variable moisture levels, an indicator that the species may per- ( n well as an urban street tree. Vjivly emerged foliage of Amur maackia has a silvery sheen. Upright racemes of small cream- colored flowers appear in July, a time when few other trees are blooming. Amur maackia's hark is slightly exfoliating with handsome shades of copper and tan. It is especially strik- ing when backlit. Professor Jin Tieshan of the Hei- longjiang Academy for Forestry reported that Amur maackia's dark- colored wood is very valuable and in the 1990s it was commonly exported to Japan. He also pointed out that on twigs the young sapwood is a light greenish tan, while the older heart- wood takes on a dark brown color. The wood is exceptionally hard and rot resistant; traditionally, it has been used for fencing in China, simi- lar to the use of black locust wood in the United States. NACPEC explorers collected 3 accessions of this species in 1993 in Heilongjiang. Collection HLJ085 was made along Jiang Po Lake, where it grew along the high water line in thin, sandy soils overlaying rock. It was clear that the trees had to toler- ate wet soils when the water levels were high and then very droughty conditions when the water level dropped. Adaptability to these kinds of natural conditions suggests that this species might also he adapted to the periodic root flooding and droughts that plague urban street trees. At another site in Heilongji- ang, small, stunted Amur maackias were growing on a rocky, ancient lava flow along a stream edge. This area was subject to alternating peri- ods of flooding and drought. Few other woody plants could survive there, but these trees were able to withstand the difficult environment, growing out of fissures in the rock. We tried two different treatments to soften the hard outer coats of Amur maackia seeds from collection PAUL MEYER 70 Arnold id 68/2 Amur niaackia bears upright racemes of creamy white flowers in midsummer. Clean ^reen foliage and exfoliating bark add ornamental appeal to Amur maackia. HLI03 1 . One group of seeds was given a 24-hour soak in hot water and a second group of seeds was scari- fied in sulfuric acid before being sown. Both treat- ments resulted in excellent germination. Three 16-year-old speci- mens are growing near my home on the grounds of the Morris Arboretum. These Amur maackias stand 18 feet (5.5 meters) tall and are 5 inches (12.7 centimeters) DBH (diameter at breast height). They have attrac- tive foliage, flowers, and hark, and are handsome in every season of the year. They are growing on a hot, sunny, south-facing slope and have never exhibited stress in times of drought. Maackia anmrensis is cer- tainly proving itself to be a handsome, tough, adapt- able shade tree that should be used more widely in stressful urban sites. Bibliography Pai, I. G. B. and W. R. Graves. 1995. Seed source affects seedling development and nitrogen fixation of Maackia amurensis. Journal of Environmental Horticulture 13:142-146. Paul W. Meyer is the F. Otto Haas Director of the Morris Arboretum of the University of Pennsylvania in Philadelphia. Pennsylvania. I Farges Filbert Corylus fargesii Anthony S. Aiello The attractive pyramidal form of Farges filbert. j ne of the goals of plant I 1 exploration is to intro- I duce new species into ! cultivation, and it is a rare and j exciting opportunity for any i plant collector to do so. Corylus fargesii (Farges filbert) was first i described in China by West- ern botanists in the late 1800s and early 1900s. Although herbarium specimens were : collected during this "golden i age" of plant exploration, i there is no evidence that liv- I ing specimens were grown in arboreta and botanic gardens i from these early collections. The first NACPEC collection of C. fargesii occurred on the 1996 expedition to Shaanxi I and Gansu, and it was col- lected again on the 2005 expe- dition to Gansu (identified by collector numbers QLG-231 and NACPEC05-047, respec- tively). Until the introduction of Farges filbert seeds to the United States in 1996, little i was known or written about ; this species. I Of the many taxa collected by NACPEC over the past twenty years, few arouse more excite- { ment than Corylus fargesii. The trees display : exfoliating tan and copper bark that rivals the : most attractive birches and is especially remi- I niscent of river birch, Betula nigra. According i to the Flora of China, Farges filbert grows to ! 40 meters (131 feet) tall and occurs naturally in ! mountain valley forests at elevations from 800 to 3000 meters (2,625 to 9,843 feet) in southern ■ Gansu, Guizhou, Fienan, Hubei, Jiangxi, south- ern Ningxia, Shaanxi, and northeast Sichuan (Chengkou Xian). During the 1996 expedition, Farges filbert was collected in eastern Gansu at the Xiao Long Shan Forest Bureau, Dang Chuan Forest Station. In their field notes, the collec- tors described it as a truly beautiful tree with exquisite bark. The parent trees had reached 12 to 15 meters (39 to 49 feet) tall and were found growing among rocks in sandy silt loam soil approximately 2 meters (6.6 feet) above a stream in open woodland. I 72 Arnoldia 68/2 Farges filbert displays exfoliating bark similar to that of river birch. On the 2005 NACPEC expedition to southern Gansu, on a morning when we shared our hike through pastures and woodland with numer- ous cattle, we were fortunate to encounter and collect C. fargesii in Zhou Qu county, near the Sha Tan Forest Station. The parent plants were growing in a mesic mixed deciduous forest and were located a few meters above a stream. Many C. fargesii were seen throughout a small area; all of these trees had been heavily coppiced hut had resprouted vigorously. As in 1996, we were impressed by the beautiful exfoliating hark. Coryhis fargesii is now well established at all of the NACPEC member gardens and in several other North American public gardens. Trees from the 1996 collection are doing especially well at the Morris Arboretum, where we have 10 plants from this accession, all of which show remarkably similar growth habit and size. These trees have grown quickly, reaching 25 to 30 feet (8 to 9 meters) after 13 years, with strong central leaders and very uniform broadly ovate habits. The trees exhibit some variation in the level of exfoliation and color of the bark, which ranges from a deep copper to a pale cream color. Farges filbert has clean summer foli- age with no insect or disease problems, and turns a good yellow in autumn. Our plants are growing in several locations, with slight differences in soil pH and all with evenly moist, well-drained soils. Farges filbert has been propagated suc- cessfully from seeds and by grafting, but with only marginal success from stem cut- tings. The diversity of conditions under which it is growing successfully indicates broad adaptability from the central Mid- west to New England and south to the mid-Atlantic states. The species appears to he fully cold hardy in USDA Zones 5 through 7 (average annual minimum tem- peratures -20 to 0°F [-29 to -18°C]). This tree's highly ornamental exfoliating bark and rapid growth rate indicate great poten- tial as an ornamental tree for a range of situations, and it promises to he an excel- lent addition to landscapes in the future. Literature Cited Aiello, A.S. 2006. Plant collecting on the eaves of the world. The Plantsman 5(41; 220-225. Aiello, A.S. and S. Dillard. 2007. Coiylus faigesii: A New and Promising Introduction from China. Ptoc Inti. Plant Prop. Soc. 57; 139-143. Grimshaw, I. and R. Bayton. 2009. New trees: recent introductions to cultivation. Royal Botanic Gardens, Kew, England. Wu, Zheng-yi and Peter H. Raven, eds. 1994. Flora of China. Missouri Botanical Garden Press. St. Louis. Anthony S. Aiello is the Gayle E. Maloney Director of Horticulture and Curator at the Morris Arhoretum of the University of Pennsylvania in Philadelphia, Pennsylvania. Chinese Ashes Fraxinus spp. Kris R. Bachtell and Olivia Siegel S ince its discovery in Detroit, Michigan, in 2002, the emerald ash horer (EAR), Agrilus planipennis, is estimated to have killed over 40 million ash trees in southeastern Canada and in 14 states throughout the central and eastern United States. Native to Asia, EAR probably arrived in North America by ship in solid wood materials used for packing freight. This inseet's impact has cost municipalities, property owners, nursery operators, and the for- est products industry tens of millions of dollars. It appears that no North American ash species is resistant to this pest, so all are threatened — there are an estimated 8 billion ash trees currently growing in the United States. On the few ash species that have been studied in China, EAR is usually a second- ary or periodic pest, infesting only stressed trees and not necessarily resulting in tree mortality. Most outbreaks in China have been associated with urban and restora- tion plantings involving North American species, particularly green ash [Fraxinus pennsylvanica] and velvet ash (F. velu- tina], both of which have been extensively planted in many northern Chinese cities. It is extremely important to gain access to Fraxinus species from China to test the full range of EAR response and to assess the adaptation of Asian ash species to American conditions and their appropri- ateness for urban landscapes. There are 22 Fraxinus speeies listed in the Flora of China. Some of these speeies are tropical, and therefore not suitable for regions of the United States currently under siege by EAR, but they are of potential utility for expanding the range of ash adaptation or for responding to EAR if the pest proves to be adapted to tropical or subtropical areas in the New World. Collecting seeds of Manchurian ash [Fraxinus mandshurica] in China. During previous NACPEC expeditions, col- lecting Fraxinus species had not been a primary focus. Typically, there were too many other more exciting species to collect and there was no reason to focus on ash. With the invasion of EAR this changed. A 2006 NACPEC-sponsored grant request was funded by the USDA and sup- ported contract collecting of native Fraxinus seeds in China by Kang Wang of the Reijing Rotanic Garden from 2007 through 2010. Addi- 74 Arnohlio 6H/2 Fraxinus insularis foliage and seeds. tionally, the 2008 NACPEC expedition to Shaanxi Province focused on collecting Fraxinus in the hotanically rich Qinling mountain region. We collected several thousand seeds of five Fraxinus species there. Several of these species are poorly rep- resented in the United States; for example, Pax's ash (F. paxi- ana] and island ash (F. insu- laris] are being grown at only two or three botanical institu- tions. We made several collec- tions of these species, along with Chinese ash [F. chinensis), Manchurian ash [F. mandsh- urica], and Chinese flower- ing ash (F. stylosa). Of these, Manchurian ash is probably the best known, since it is a large-growing tree with an estab- lished landscape value (the cultivated selection 'Mancana' is common in the nursery industry). Other species, such as island ash and Chinese flowering ash, are medium-sized trees that may have urban use potential if they prove adapt- able. Pax's ash is a shrubby species that pos- sesses extremely large flower clusters, hut its landscape potential is unknown. Twenty-six Fraxinus seed collections have been made in China, resulting in 1 1 different taxa currently represented by over 600 plants. Ash seed is relatively easy to harvest, clean, and germinate, so the degree of success grow- ing these plants has been good. Surplus seeds will be preserved in the USDA's germplasm repository in Ames, Iowa, and made available for scientific research throughout the world. Currently, plants from the 2008 Shaanxi expe- dition are being used by leading researchers in efforts to identify relative susceptibility and resistance of different ash species to EAR. The seed collections will also aid research in iden- tifying appropriate genetic material to create new North American-Asian ash hybrids that combine resistance genes from the Asian spe- cies with useful characteristics from the North American species. Researchers Koch et al. recently cited the importance of the NACPEC Fraxinus collections to their genetics and breed- ing efforts, noting that the previous lack of Asian ash accessions in the United States had greatly restricted the potential for hybridiza- tion. Future collecting expeditions are planned and many additional research questions related to EAR still need to be answered. Bibliosraphy Flora of China. (1996) Retrieved December 15, 2006 from http://flora.huh.harvard.edu/china/mss/ volume 1 5/Oleaceae. published. pdf Koch, T. L., D. W. Carey, M. E. Mason, and M. N. Islam-Faridi. (online publication in process). Overcoming obstacles to interspecies hybridization of ash. In: Proceedings of the Symposium on Ash in North America. March 19-21. 2010. Purdue University, West Lafayette, IN. Liu, H., Bauer, L.S., Gao, R., Zhao, T., Petrice, T.R., and Fiaack, R.A. (2003). Exploratory survey for the Emerald Ash Borer, Agrilus planipennis (Coleoptera: Buprestidae), and its natural enemies in China. The Great Lakes Entomologist. 36(3 ik 4): 191-204. Poland, T.M., ik McCullough, D.G. (2006). Emerald ash borer: Invasion of the urban forest and the threat to North America's ash resource, fournal of Forestry. April/May 2006: 118-123. Kris R. Bachtcll is Vice President of Collections and Facilities at the Morton Arboretum in Lisle, Illinois. Olivia Siegel is Development Coordinator at the Aspen Center for Environmental Studies in Aspen, Colorado. Manchurian Catalpa Catalpa bungei Richard T. Olsen and Joseph H. Kiikbiide, Jr. F amiliarity breeds contempt — for catalpa. The genus has nine accepted species, two in eastern North America, four in the West Indies, and three more in eastern Asia. The North American species [Catalpa bignonioides and C. speciosa) are the best known in the West, often overlooked as waifs in urban landscapes or as country trees, too large or messy for mod- ern landscapes, yet tolerated when in flower in late May to lune. Perhaps this sentiment per- meated the group conscience on NACPEC's 1994 Wudang Shan expedition, when, on the first day of collecting, they were underwhelmed by Kevin Conrad's sighting of a lone pollarded catalpa in a field of soybeans and corn. Con- rad, representing the United States National Arboretum (USNA), was on his first expedition to China, the wide-eyed and energetic newbie in a field of veteran collectors. Reluctantly, the group stopped to collect seed and vouch- ers of what was identified as the Manchurian I catalpa, Catalpa bungei. As it turned out, it ; was the only catalpa seen on the trip and proved to be one of the most important collections ' of the expedition. In 1831, Alexander Andrejewitsch von Bunge collected herbarium specimens of a catalpa near Beijing, which C. A. Meyer later identified and described as a new species, and named in honor of Bunge. Catalpa bungei and C. ovata are the two most commonly cultivated species of i catalpa in China, both in agroforestry for their high quality wood and in religious circles as one of the "jeweled trees" of Chinese Buddhism. There is much research published in Chinese journals on propagation, breeding behavior, and ; sylviculture of C. bungei, but this emphasis on its importance has not filtered to the West, where appreciation for the species is lacking. Early introductions of catalpa into Europe were erroneously ascribed to this new species, even as they came into flower with upright, many- flowered panicles of small yellow or yellowish- green flowers that clearly identified them as C. ovata. The inflorescences of C. bungei are corymbose, with fewer but larger flowers con- spicuously spotted with piirk, effectively col- oring the flowers rose. The first introduction of true C. bungei is attributed to the Arnold Arboretum in 1904, when wild-collected seeds were acquired (via American diplomat E. T. Williams) from the vicinity of Beijing. These seeds — and subsequent plants — were distrib- uted to European botanical institutes, but the species remains almost nonexistent in cultiva- tion, a victim of confusion generated by earlier misidentifications. The Arnold Arboretum still has a living plant of this accession (AA# 12927), which has stood sentinel above the lilac collec- tion for over a century. The great plant collectors E. H. Wilson and F. N. Meyer did not overlook catalpa on their forays across China in the early twentieth cen- tury. Wilson, collecting for the Arnold Arbore- tum, never knowingly collected C. bungei, but based on herbarium specimens from his trips, his collections of C. fargesii (syn. C. duclouxii] are a mixed bag of phenotypes, some of which agree with C. bungei. But Meyer, collecting for the USDA, collected what he labeled C. bungei on five separate occasions, calling the species "one of the finest flowering trees in the world". The taxonomy of these species is not well resolved, but based on recent phylogenetic anal- yses, this group forms a clade separate from the North American and West Indian species. The USNA conducts on-going taxonomy and breed- ing work in the genus Catalpa, and C. bungei has taken center stage, thanks to its beautiful flowers, disease resistant foliage, and general adaptability. In our search for germplasm to introduce into our breeding program, we have scoured both domestic and foreign nurseries for material of C. bungei and related species. 76 Arnoldia 68/2 I i n We have yet to find a nursery offering the real C. bungei. Our search of botanical gardens and arboreta yielded only three accessions in North America that are true-to-type, two of wild ori- gin: the original C. bungei 12927 at the Arnold, and C. bungei WD009 from the Wudang Shan trip in 1994. Unknowingly, NACPEC had made the first collection of C. bungei in 90 years, pro- viding germplasm for urban tree breeding and increasing our knowledge of an underutilized and underappreciated genus. Richard T. Olsen is a Research Geneticist and Joseph H. Kirkbride, Jr. is a Plant Taxonomist, both at the United States National Arboretum in Washington, District of Columbia. iilOyWiT M fro. till, collootloo nn om oron u ArooU ArboracuB accaaaloa ARNOtO ARM>Rrn M -' l VlAfrU CUrVi \ wt. .!>*>•> y r .' TWtV^it. - h '<■ '■- MM The Magazine of the Arnold Arboretum VOLUME 68 • NUMBER 4 • 2011 CONTENTS Ainoldia (ISSN 0004-2633; USPS 866-100) is published quarterly by the Arnold Arboretum of Harvard University. Periodicals postage paid at Boston, Massachusetts. Subscriptions are $20.00 per calendar year domestic, $25.00 foreign, payable in advance. Remittances may be made in U.S. dollars, by check drawn on a U.S. bank; by international money order; or by Visa, Mastercard, or American Express. Send orders, remittances, requests to purchase back issues, change-of-address notices, and all other subscription-related communica- tions to Circulation Manager, Ainoldia, Arnold Arboretum, 125 Arborway, Boston, MA 02130- 3500. Telephone 617.524.1718; fax 617.524.1418; e-mail arnoldia@arnarb.harvard.edu Arnold Arboretum members receive a subscrip- tion to Ainoldia as a membership benefit. To become a member or receive more information, please call Wendy Krauss at 617.384.5766 or email wendy_krauss@harvard.edu Postmaster: Send address changes to Ainoldia Circulation Manager The Arnold Arboretum 125 Arborway Boston, MA 02130-3500 Nancy Rose, Editoi Andy Winther, Designei Editoiial Committee Phyllis Andersen Peter Del Tredici Michael S. Dosmann William |Ned) Friedman Kanchi N. Gandhi Copyright ©2011. The President and Fellows of Flarvard College 2 Tapping the Underappreciated Plant Diversity of the Eastern United States Rick f. Lewandowski 14 Leaf-out Dates Highlight a Changing Climate Caroline Polgar and Richard Primack 23 Not-So-Traditional Chinese Medicine: The Example of Donglingcao [Isodon rubescens) Eric S. f. Harris 31 2010 Weather at the Arboretum Bob Famiglietti 36 The Family Tree: Prunus ‘Hally Jolivette' Miles Sax Eront and back covers: Tiillium luteum in bloom at Mt. Cuba Center in Delaware. Photo by Rick J. Lewandowski. Inside front cover: Lilac Sunday 2010 was sunny but cool, though the year as a whole was on the warm side. For more details about last year's weather at the Arboretum turn to page 31. Photo of hybrid lilac [Syiinga oblata ssp. dilatata x S. oblata, AA#144-8TH) by Nancy Rose. Inside back cover: Arboretum horticultural apprentice Miles Sax profiles a favorite flowering cherry, Prunus 'Hally Jolivette'. Photo courtesy of New York Botanical Garden/Mark Pfeffer. 7)k ARNOLD ARBORETUM of HARVARD UNIVERSITY ALL PHOTOS BY RICK I LEWANDOWSKl tXCEP WHERE NOTED Tapping the Underappreciated Plant Diversity of the Eastern United States Rick /. Lewandowski T he romance and intrigue of plant discov- ery and acquisition continues to entice plant explorers, most often to remote and exotic places far away from the United States. Though early explorers and botanists (including the Bartrams, the Michauxs, Nuttall, Torrey, Gray, and Harper) described the vast richness of eastern North America's flora, its range of diversity and adaptability continue to he under- appreciated and understudied to this day. In efforts to more fully document and explore its potential, Mt. Cuba Center, near Wilmington, Delaware, is among a handful of public gardens currently active and engaged in exploring and promoting this rich flora. PLANT EXPLORATION WITH PURPOSE The forests of eastern North America are replete with a remarkable array of plant communi- ties, habitats, and plant species. Through the vision and resources left by our founders, Mt. Cuba Center has dedicated significant energy The Dogwood Path forms an intimate canopy adjacent to Mt. Cuba Center's meadow. It showcases many plants in sophisticated layers, from tall trees to low-growing wildflowers. Plant Exploration 3 Gorge rhododendron {Rhododendron minus) is one of the native species being documented, collected, and evaluated. The wild popu- lation seen here on Flag Mountain in Alabama is at home in the hot and humid southern end of its range on shady, dry, acidic slopes. to exploring habitats throughout the eastern United States from Pennsylvania and Delaware through the Carolinas, Georgia, and Alabama. Throughout these states we have discovered that there is an enormous reserve of genetic diver- sity worthy of greater study and appreciation. Plant exploration is an essential component of Mt. Cuba Center's commitment to study and assess the adaptability of native plants for horticultural use. In addition to enriching the gardens with documented, wild-collected, seed-grown plants from a range of provenances, detailed field data gathered from this effort has provided us with a greater understanding of habitats, distribution, and plant associations. This documentation has potentially far-reaching implications for horticulture, landscape design, and conservation. During the past 11 years, Mt. Cuba Center staff members have conducted nearly 80 field expeditions in the eastern and southeastern United States in 11 states. Over 1,150 docu- mented collections have been made, repre- senting 619 taxa of herbaceous and woody plants. Regular collaboration with numerous partners — including other public gardens, uni- versities, state and federal agencies, industry, conservation organizations, and private indi- viduals — has afforded us the opportunity to observe and sample plant diversity in a wide range of habitats. In addition to hroad-hased sampling of her- baceous and woody taxa, Mt. Cuba Center's field work in recent years has also focused on sampling specific taxa in order to obtain broader genetic diversity, obtain taxa from the edges of their ranges or from disjunct populations, and assess potential variation of selected plant spe- cies for wider landscape use. Some of the highest priority woody plant taxa for targeted sampling currently include: Fothergilla gardenii, Fothei- gilla major, Halesia Carolina, Halesia diptera. The Copeland Family Legacy MT. CUBA CENTER is the 589-acre former estate of Mr. and Mrs. Lammot du Pont Copeland. Over a 65-year period, beginning in 1 937, gardening became a consuming passion for the Copelands. During the formative years of their estate and garden, the Copelands engaged a number of design- ers including Thomas Sears, Marian Coffin, and Seth Kelsey to assist in creating a series of formal and informal landscapes surrounding their home. These provided structure and a unique identity to their ever-expanding gardening interests. By the late 1970s Mr. and Mrs. Copeland had begun to refine their gardening interests, focusing more and more on native plants of the eastern United States. With passion, vision, and hands-on garden development, the Copelands and their staff, including their first director. Dr. Richard Eighty, created some of the mid-Atlantic region's most attractive and diverse native plant gardens. In 2002, a year after Mrs. Copeland's death at age 94 (predeceased by Mr. Copeland in 1983), Mt. Cuba Center officially became a private non-profit organization, with a mission to display, study, and promote the broader use of the flora of the eastern United States, with particular emphasis on the Piedmont physiographic region. Today, a decade later, well documented and botanically diverse gardens, horticultural research and introduction programs, as well as extensive education and public tour programs are beginning to fulfill the Copelands' hopes for their beloved estate. The Copelands’ Colonial Revival home was completed in and today serves as the hub of administrative and education activi- ties at Mt. Cuba Center. In the foreground, a dense stand of native prickly-pear cactus (Opuntia humifusa) spills over a rocky ledge Plant Exploration 5 Halesia tetraptera, Illicium floridanum, Kalmia latifolia, Leucothoe axillaris, Leucothoe fontanesiana. Rhododendron catawbiense. Rhododendron colemanii. Rhododendron minus. Rhododendron pruni- folium, Stewartia mala- codendron, Stewartia ovata. Viburnum acerifolium, and several deciduous Rhododen- dron species. SOME EXAMPLES OF INITIATIVES CURRENTLY UNDERWAY: Silky camellia (Stewartia malacodendron) flowering in mid June at .Vlt. Cuba Center is a show-stopper. Sampling Stewartia Diversity Silky camellia (Stewartia mal- acodendron] and mountain camellia (Stewartia ovata) are attractive native North Ameri- can deciduous shrubs or small trees that have been underap- preciated for their horticultural value and as biological indica- tors of stable, botanically rich habitats. Both species have highly attractive, non-fragrant, white flowers that open daily over a one to three week period from mid May to late June, depending upon the region. The distribution of these two species is often discontinuous, with highly variable popula- tion sizes. Silky camellia is pri- marily found in the coastal plain and Piedmont from Virginia to Florida and west as far as east- ern Texas. Mountain camellia is naturally dis- tributed in the Piedmont and mountains from Virginia to Georgia and Alabama, reaching its western limit in southern Kentucky and Ten- nessee; a few disjunct populations can be found in the coastal plain of Virginia and North Caro- lina. While there are pockets of large popula- tions, most populations are small and isolated, which is likely to have resulted in genetic iso- lation. North-central Alabama is one (possibly the only) place where the range of these two species overlaps, with plants of both species growing in close proximity to each other. In 1999, Mt. Cuba Center began targeted field work to document populations and collect seeds of both species from across the breadth of their ranges. More than 120 documented seed collections of these two species from 7 states have since been made. The Stewartia Working Group (SWG) was formed in 2007 as a collaboration to develop ex situ repositories for the extensive documented seed collections already made and to study, long-term, the variation in these two eastern 6 Arnoldia 68/4 These four images show variation in the filament color of Stevvartia ovata flowers on separate plants. North American species. The SWG currently includes the Birmingham Botanical Garden, Alabama; Mt. Cuba Center, Delaware; Polly Hill Arboretum, Massachusetts; Smithgall Arboretum, Georgia; Yew Dell Gardens, Ken- tucky; and Heritage Seedlings nursery, Oregon. Much of the success of the SWG is due to the knowledge, guidance, and assistance of stewartia authority lack Johnston. He has systematically identified countless stewartia populations and guided the group to them in order to observe and sample both silky camellia and mountain camellia. As a result, a signifi- cant portion of the range of these two species has already been sampled. Much remains to be learned, though, about the variation, habi- tats, distribution, propagation, production, and adaptability in cultivation of both species. Even so, the SWG is making significant progress in representing a broad range of native stewartia diversity in cultivation. Provenance-based collecting such as that with Stewartia malacodendron and Stewar- tia ovata offers an important window into the variation of species and potential preservation of genetic variation. It also affords emergent opportunities to encourage research as well as selection of superior forms. Some other important provenance-based collections of interest include Leucothoe axillaris (6 collec- tions), Leucothoe fontanesiana (14 collections). Rhododendron coleinanii (8 collections), and Rhododendron prunifolium (7 collections) to mention just a few. In many cases these taxa are represented in cultivation by few or no known wild- documented populations. Documented col- lections in our public gardens are crucial for Plant Exploration 7 Stewartia ovata is frequently found in rich mesic woodlands of the upper Piedmont and mountains of the southeastern United States where it can become a small tree. The specimen seen here is growing in Georgia’s Warwoman Wildlife Management Area. expanding our appreciation of the variation in these species, properly identifying cultivated forms and hybrids of species, and providing documented, known-source material for horti- culture and science. ON THE EDGE Unfortunately, much of our pre-conceived bias about plant adaptability is based upon limited experiences with plants from their core ranges. Assumptions about adaptability become rules regarding how plants perform in the landscape, but are not always correct. In eastern North America, the range of many species is fre- quently broader than we know and is not fully represented in cultivation. Success and failure with a number of native plants in the garden at Mt. Cuba Center has informed our opinions about the need to more thoroughly explore the distribution of native eastern North American herbaceous and woody plant species. As a result, in the past several years field work has focused on locating, docu- menting, sampling, and growing a number of species from the edges of their ranges. Rhododendron minus Gorge rhododendron [Rhododendron minus] is found in the mountains of North Carolina, South Carolina, Georgia, and Tennessee, growing on well-drained slopes and outcrops. However, there are also many discontinuous populations of this species found into southern Alabama and Georgia. The location and environmen- tal conditions of these southern populations places them under significantly greater heat and drought stress for extended periods throughout the growing season than mountain populations. 8 Arnoldia 68/4 Alabama populations of Rhododendron minus frequently produce attractive pink flower trusses. While gorge rhododendron and its close relative, Carolina rhododendron [Rhododendron caro- linianum], are attractive hroadleaved evergreen shruhs that have been exploited for breeding and selection for many decades, their summer adapt- ability to landscape stress in the mid-Atlantic has been suspect. Over the past several years, Mt. Cuba Cen- ter has made 26 collections of Rhododendron minus from throughout the southern end of its range to observe garden adaptability and variation; this work continues. It is interest- ing to note that nearly all the populations of gorge rhododendron from the southern end of its range develop attractive pale to dark pink flower trusses that bloom later than moun- tain populations despite their southern nativ- ity. Through the guidance of rhododendron expert Ron Miller, we have also obtained and grown seeds from isolated populations of white- flowering forms found in Alabama and Georgia. It is our hope that long-term observation and assessment of these plants may yield opportu- nities for wider introduction of these southern genotypes into cultivation as well as breeding and selection work. Additionally, the inclusion of these plants in our living collection provides opportunities for continued taxonomic study of this interesting group of rhododendrons. Rhododendron catawbiense Catawba rhododendron [Rhododendron cataw- hiense) generally ranges from the mountains and upper Piedmont of the Carolinas and Tennessee northeast into Virginia and West Virginia above elevations of 3,000 feet (914 meters). Because of hot and humid summers (especially the warm night temperatures) in the mid-Atlantic region, this rhododendron struggles to survive in the typical suburban landscape. Again, with the knowledge and assistance of noted azalea and rhododendron expert, Ron Miller, we have been able to document and collect seeds from 12 populations along the extreme southern edge of the range of this rho- dodendron. In remote and difficult-to-access Creating a Haven for Herbaceous Plants MT. CUBA CENTER'S garden and living collec- tion is an integrated matrix of plants intended to delight and inspire guests. It is our goal to pro- vide guests with an understanding of how beau- tiful gardens are created and maintained using environmentally appropriate landscape manage- ment practices. Through this approach the garden and living collection provides opportunities for sophisticated layers of herbaceous plants that play an important role in the structure of the garden, integrating with and complementing the woody plant layers throughout the growing season. Our gardens are well-known for an extraordi- nary variety of herbaceous plant species and cul- tivars that contribute character to the woodland garden setting. Of Mrs. Copeland's favorite wild- flowers, trillium [Trillium spp.) was the queen. To this day, trilliums continue to be among the most coveted of all wildflowers grown in our garden. Over the past 20 years, we have developed expertise in the propagation and production of trillium species from seed. In 2001, Mt. Cuba Center was recognized for significant plant exper- tise with trillium propagation, production, and ex situ preservation by receiving North American Plant Collections Consortium (NAPCC) member status as an official holder for the genus Trillium. At present, the collection includes 84 taxa repre- sented by more than 470 accessions. To broaden the genetic diversity of trilliums available in cultivation and to support ex situ preservation, we have continued to target tril- lium in our plant exploration activities. Over the past 11 years, we have made 110 collections of wild-documented trillium species, varieties, and unique forms. These include: Trillium catesbaei, T. cernuum, T. cuneatum, T. decumbens, T. dis- color, T. erectum, T. flexipes, T lancifolium. T. luteum, T. nivale, T. rugellii, T. stamineum, T. underwoodii, and T. vaseyi. A number of hybrids and unique forms of several trillium species have also been collected. While trillium is an important focus, much work at Mt. Cuba Center continues on a very diverse assemblage of native herbaceous plants in order to contribute to the richness and diversity of plants worthy of wider use by the gardening public. Trillium decumbens Trillium simile Trillium discolor 10 Arnolclid 6H/4 altitude montane habitats far- ther north. Evaluation of seed- lings from these populations is in the early stages, but as with gorge rhododendron, observa- tion and assessment may pro- vide opportunities for broader use of this species in cultiva- tion along the mid-Atlantic seaboard or for incorporation into breeding schemes. Kalmia latifolia Catawba rhododendron [Rhododendron catawbiense) flowers heavily even in dense shade in Alabama. However, its flowers are pale lavender pink rather than the deeper violet purple of northern populations. sites along rivers and ravines in northeastern Alabama, Catawba rhododendron grows on sandy benches at elevations ranging from 600 to 1,200 feet (183 to 366 meters). The climate of the Alabama Catawba rhododendron habitats is much warmer and more humid than higher Mt. Cuba Center has had a long-standing love affair with mountain laurel [Kalmia lati- folia] because natural popula- tions occur on the property and, more importantly, because the Copelands used this attrac- tive broadleaved evergreen frequently in their garden. Mountain laurel is common throughout the eastern and northeastern United States all the way to Maine. Interest- ingly, it is also distributed into southern Alabama, the Florida panhandle, and eastern Loui- siana. While much selection and breeding work has been done with mountain laurel in the northeastern United States, there has been a limited emphasis on documenting, col- lecting, growing, and assessing the adaptability of mountain laurel from the extreme south- ern end of its range. Unlike populations of Kal- inia latifolia in our area that grow in dry, shady upland wood- lands, populations of mountain laurel in the Deep South are frequently found in sandy, well-drained, shady riverine habitats, sometimes well within the flood zone of streams. Recently, 20 collections of mountain laurel from Alabama, Florida, and Louisiana were made to assess the long-term stress tolerance of these provenances compared Plant Exploration 1 1 In the southern end of its range Kalmia latifolia is frequently found in riverine habitats where flooding is common. Flowers of a Kalmia latifolia specimen growing in Coosa County, Alabama. 12 Arnoldia 68/4 Mountain laurel was among the Copelands’ favorite shrubs, serving as a year round evergreen that explodes into flower in early summer. to widely cultivated forms. This work is in its infancy but represents an important long-term opportunity to assess adaptability, disease and pest resistance, and ornamental value. ASSESSING ADAPTABILITY Most gardeners in the mid-Atlantic region are unfamiliar with Florida anise [lllicium flori- danuin). For those who are, they usually con- sider it to be, at best, marginally hardy in our area. Despite this fact, Mrs. Copeland grew this lovely hroadleavcd evergreen shrub in her garden for nearly two decades. Its supple ever- green foliage, modestly formal upright habit, adaptability to shade and drought, as well as its attractive burgundy red flowers in early spring have made Florida anise a modern favorite of staff and visitors to this day. Florida anise is common in bottomland for- ests, along lakes and streams, and on the edges Dark red flowers of Florida anise [lllicium floridanum) stand out in the spring landscape. of wetland communities throughout much of southern Mississippi and southern to central- northern Alabama. Despite its common name. Plant Exploration 13 A flowering dogwood [Cornus florida) blooms in the spring mist along the Woods Path at Mt. Cuba Center. Florida anise is found only in the panhandle of Florida. In order to more systematically assess the garden adaptability and hardiness of Illicium floridanum, we began sampling pop- ulations on the northern edge of its range in Alabama several years ago. Through this work, 1 1 documented collections have been made, including samples from disjunct populations at the northern edge of the species' range in Alabama. Through long-term evaluation and distribution, we hope to broaden the potential for using Florida anise in the mid-Atlantic and surrounding regions. WHAT'S NEXT? The flora of the eastern United States still has much to offer. The plants mentioned here are just a few of the many that deserve broader long-term study. Through Mt. Cuba Center's long-term commitment to observing, docu- menting, and sampling the flora of the eastern United States, we hope that a broader segment of this flora will be appreciated and used by the gardening public. Rick Lewandowski is Director of Mt. Cuba Center near Wilmington, Delaware. RICHARD PRIMACK AND CAROLINE POLCAR Leaf-out Dates Highlight a Changing Climate Caroline Polgar and Richard Primack T he arrival of spring is heralded each year by striking displays of flowers on trees and shrubs. Perhaps less conspicuous than the blooming of flowers, the emergence of new leaves on woody plants marks the onset of the growing season and controls a host of eco- system functions. While to the untrained eye It may seem as though the leaves come out at the same time each year in one big burst, there are actually relatively consistent differences among species in leaf-out dates, as well as large differences from year to year in the timing of leaf out. The study of the timing of leaf out (and other natural annual phenomena) is known as phenology. Much of what we know about the physiology of leaf and bud development, and the mecha- nisms behind various leaf-out strategies, comes Clockwise from top left: Birches tend to leaf out early in the spring, while hickories tend to leaf out in late spring. Red oaks and beeches tend to leaf out in the middle of spring. Leaf-out Dates 15 Young red maple {Acer rubrum) leaves begin to expand in the spring. from research done in the past by tree physi- ologists and foresters who were interested in the connections to tree growth and timber har- vests. Over the past few years, however, the range of people interested in leaf-out phenol- ogy has grown, as have the methods employed to study it, largely as a result of the relevance of this phenomenon to global climate change. New technology, including satellite data, is now being used to monitor leaf-out timing over wider areas than was possible in the past. Forest and ecosystem ecologists are connecting these leaf-out date observations to larger issues of global climate change, with implications for carbon cycles, the availability of fresh water, and wood production. Monitoring leaf out The recent resurgence of interest in the phenol- ogy of woody plants has led to leaf-out moni- toring projects around the world. For example, over the past twenty years Dr. John O'Keefe and other ecologists at the Fiarvard Forest in central Massachusetts have been recording the dates of leaf emergence of individual trees and shrubs each spring, including such common species as red maple {Acer rubrum), white oak {Quercus alba), and red oak {Quercus rubra) (O'Keefe 2010). The Japanese Meteorological Agency has been recording leaf out, flowering times, autumn leaf color, and other phenological data of individual marked plants in phenological gardens at over 100 weather sta- tions since 1953 (Ibanez et al. 2010). Ginkgo {Ginkgo biloba), also known as maidenhair tree, is one of the species being moni- tored. The International Phenological Gardens (IPG) project, a network of botan- ical gardens across Europe, has been collecting simi- lar data on leaf-out dates of individual plants since 1951 (Menzel 2000). Other leaf-out datasets go back even further, including one that Flenry David Thoreau compiled in the mid-nineteenth century on plants in Concord, Massachusetts. Findings from these studies indicate that there can be large year-to-year variability in the tim- ing of leaf out, depending on the weather, and that there tends to be relative consistency in the order of leaf out of species from year to year (Lechowicz 1984). Obtaining annual observations of leaf-out dates can be quite time and labor intensive, often limiting studies to a small area around a field station or a small number of species. To measure leaf out on a larger scale, remote sens- ing has emerged as a valuable new tool that can monitor an entire plant community or eco- system consisting of many different kinds of plants. Remote sensing studies typically use data obtained by sensors on orbiting satellites, such as the Advanced Very Fligh Resolution Radiometer (AVFIRR) and the Moderate-reso- lution Imaging Spectroradiometer (MODIS), or equipment on Landsat satellites. Satellite sys- tems vary in their spatial resolution, frequency of coverage, and types of data gathered. Scien- 1 6 Arnoldia 68/4 The average onset of leaf out in (A) southern New England from Landsat (1984- 2002) and (B) the northeastern United States using MOOIS (2000-2005). These images demonstrate that later phenology oceurs at higher elevations, such as the Adirondacks and White Mountains; at higher latitudes; and in coastal areas that experience moderating ocean effects, such as Cape Cod and the Islands. The loston and New York metropolitan areas leaf out earlier because of higher temper- atures associated with the urban heat island effect; earlier leaf out is also seen in warm river valleys. Colors indicate the date on w hich half of the tree canopy has leafed out (from day 1 10 [April 20j to day 165 jlune 15|), with earlier onset shown by blue and later onset by orange and red. (image from fisher and mustaro 200"^) lists use data transmitted from these satellites to calculate the changes in the amount of green vegetation (greenness) there is in a certain area over a growing season. Analysis of graphs of greenness over time can he used to quantify important dates in the growing season, such as date of first leaf out in spring, the date at which half of the leaf cover has developed, and canopy senescence in autumn. Several recent research papers have shown that regional leaf-out data from satellites accurately match ground observations. This is particularly important because there is concern that different topographic features, such as mountains, fields, cities, and lakes, might create errors in the detection of green-up dates. In one study from Rhode Island, researchers using Landsat data were able to incorporate land- scape features into their analysis and detect a delay in leaf out at the base of hills due to cold air drainage, a delay in coastal areas due to the cooling effects of the ocean, and a one-week delay in leaf out for deciduous forests in rural areas compared to those in the nearby urban area of Provi- dence (Fisher et al. 2006). While such changes in leaf-out dates are already known from specific ground observations, the abil- ity to detect such effects using remote sensing greatly extends our ability to map leaf out over large areas. Another interesting remote sensing approach for monitoring leaf out uses phenocams, which refers to cameras placed in fixed locations that are used to record images of the leaf canopy at regular intervals, such as every hour or once a day, throughout Leaf -out Dates 17 A sequence of two photos taken at the same spot by a pheno- cam at the Harvard Forest showing leaf out over a one-week period. The picture on the top left was taken on April 30, 2009, the one on the top right was taken on .May 7, 2009. The photograph on the bottom was taken on .April 29, 2009 and shows a view over the canopy of the Harvard Forest with the phenocam below. the growing season. Dr. Andrew Richardson and others have set up phenocams in the can- opy at Harvard Forest and 1 1 other forests in the northern continental United States. These images can he analyzed using computer pro- grams to determine the seasonal trajectory of hudhurst, green-up, and senescence. Networks of these phenocams can fill in the spatial and temporal gaps between plant monitoring hy human observers and regional remote sensing images. Seven of these sites in the United States also have towers that monitor the exchange of carbon dioxide (CO 2 ) and water between the atmosphere and the forest. This combination of data from webcams, satellites, and gas sensors is providing crucial information on the relation- ship between phenology and ecosystem pro- cesses, especially carbon uptake (Richardson et al. 2009a). Leaf out and climate change Climate change is already affecting many eco- logical processes, and leaf out is no exception (Ibanez et al. 2010; Menzel 2000; Richardson et al. 2006). By analyzing long-term data on leaf- out dates, much can be learned about how the onset of spring has changed over time as tem- peratures have increased. From data collected at the IPG, researchers determined that trees in northern Europe have advanced their leaf out by an average of one week over the past fifty years (Menzel 2000). In Japan, woody plants such as forsythia (Forsythia viiidissima var. koreana), ginkgo, mulberry {Moms bombycis), and various cherry species {Pmnus spp.) leafed out an additional 2 to 7 days earlier for each 1°C increase in temperature between 1953 and 2005. At a few sites, however, ginkgo trees were actually leafing out later than they did in the past, contrary to expectations (Ibanez et al. 2010). At the Hubbard Brook Experimental For- est in New Hampshire, the leaf out onset of three native species — American beech (Fagus grandifolia], sugar maple {Acer saccharum), and yellow birch [Betula alleghaniensis ] — has advanced an average of 5 to 10 days over the past five decades (Richardson et al. 2006). Historical datasets, such as those recorded by Henry David Thoreau and Aldo Leopold, can ROBERT MAYER 1 8 Arnoldio (->8/4 also be used for these types of studies by com- paring their records to contemporary observa- tions from the same place, even if there is a lack of data between the two time periods (Hradley et al. 1999; Miller-Rushing and Primack 2008). We know that leaf out has become earlier in many areas in recent years, largely because of warmer temperatures, hut what about the future? Will the advance in spring's onset continue for all species? To answer these ques- tions, it is necessary to both be familiar with the physiology behind leaf out, and to build on what we already know about the response of leaf out to temperature. Variation in leaf-out times Trees and shrubs vary widely in leaf-out times, both among and within species. For instance, individuals will leaf out earlier in a warm, sunny location, such as a south-facing hill, than individuals of the same species located in a cold, shady location. Similarly, all individu- als of a given species will leaf out later during a cold spring than in a warm spring. Sometimes when a tree is growing on the edge of field, the exposed sunny side will leaf out earlier than the shady side. These differences aside, there is a fairly consistent pattern in the leaf-out timing of trees, shrubs, and vines from year to year. Biittonbush [CephoUinthus occidcntalis) is one of the latest native shrubs to leaf out in the sprinj;. It is seen here hlooining in inidsuniiner. In eastern Massachusetts, species leaf out over a 4 to 6 week period. Among the first plants to leaf out in the spring are such introduced ornamental shrubs as common lilac (Syringa vulgaris), honeysuckles [Lonicera spp.), and Jap- anese barberry {Berberis thunbergii), and non- native fruit trees such as apple [Malus spp.). Of native species, meadowsweet [Spiraea alba var. latifolia], quaking aspen [Populus tremuloides], hlack cherry (Prunus serotina], and grey hirch [Betula populifolia) are among the first species to leaf out. Consistently among the last species to leaf out are white ash [Fraxinus americana], white oak, and black tupelo [Nyssa sylvatica], with poison sumac [Toxicodendron vernix) and buttonbush [Cephalanthus occidentalis) often being the last of all. The pattern of leaf out is fairly consistent across the temperate zone of Europe and North America. Certain groups of plants tend to leaf out early (hirches, willows, alders, many poplars and aspens) and others late (hickories, walnuts, and ashes). So why do some species leaf out so early and other species leaf out so late? Since the func- tion of leaves is to carry out photosynthesis and provide sugars for the tree, in general it should benefit a tree to leaf out as early as possible to get the longest growing season. A tree species that leafs out in early April has four additional weeks to photosynthesize compared to a tree species that leafs out in early to mid May. How- ever, the early-leafing tree faces the danger of a late frost that will kill its leaves and damage its vessel elements, the chief water conducting tissue. This trade-off between the advantages of early growth and of late growth provides a good explanation of why certain species leaf out when they do. The stem anatomy supports this explanation, with early species tending to have smaller vessel elements that are less prone to frost damage than the larger vessel elements of later species (Lechowicz 1984; Miller-Rushing and Primack 2008). Also important is the evo- lutionary history of a plant group: If it orginated in a warmer climate, it may not have fully- adapted mechanisms for dealing with extreme cold and therefore may have different factors regulating leaf out than a plant group originat- ing in a colder climate. The vulnerability of trees and other plants to frost damage was recently demonstrated when I Leaf-out Dates 19 A late frost killed the new foliage on this oak tree. two weeks of abnormally warm weather in March 2007 triggered early leaf out all across eastern and central North America. A return of freezing weather from April 5 to 9 killed young leaves and flowers, and caused the die hack of tree canopies across the region (Gu et al. 2008). This frost damage was an example of the type of episodes of mismatches between plants and climate that may become increasingly common as climate change continues. What triggers leaf out? Leaf out is predominantly controlled by temper- ature, with plants generally leafing out earlier in warmer conditions, but warm temperature is the not only factor. In fact, for many species it is a combination of warm and cold tempera- tures along with day length that dictates when the leaves will emerge from the bud. Most temperate species, including sugar maple and quaking aspen, have a chilling requirement, meaning that a certain number of cold (gener- ally a minimum of 0 to 10°C [32 to 50°F]) days in winter are required before the buds are able to break dormancy. The exact number of chill- ing units required depends both on species and on the weather of the preceding growing season (Hunter and Lechowicz 1992; Perry 1971). Once this requirement has been fulfilled, a certain number of warm days above a certain tempera- ture threshold are then needed for leaf develop- ment to begin and buds to open. This pattern is seen in both deciduous and evergreen species. In addition, some species also have a photope- riod requirement, meaning that they will only leaf out once daylength reaches a certain num- ber of hours in the spring. In particular, long- lived trees of mature forests, such as American beech, some oak species, and hackberry [Celtis Occident alis], often rely on a combination of photoperiod and temperature cues to break dor- mancy. For these species, budbreak only occurs after specific photoperiod and temperature requirements have been met. This holds even IOWA S I ATE UNIVERSITY 20 Arnohlia 68/4 when individuals from these species are planted in subtropical climates with exceptionally high temperatures (Korner and Basler 2010). In contrast, many opportunistic species that are found early in forest succession, such as birches, hazelnuts [Corylus spp.), and poplars, do not have a photoperiod requirement to break winter dormancy. This somewhat risky strategy allows trees to respond more quickly to episodes of warm temperature in the early spring, but also creates more susceptibil- ity to late frosts. Yet a third group of species, which includes mostly ornamental plants from warmer climates, has a leaf-out strategy linked to spring temperature with minimal chilling requirements and no photoperiod requirement. The common lilac is a local example, and is one of the first plants to leaf out each spring. Learning from the past, predicting the future Using information about past phenological responses to temperature and future climate scenarios, scientists can develop models to pre- dict future phenological changes both at the spe- cies and ecosystem levels. One modeling study found that the advance in leaf-out time for most species and places is likely to continue in com- ing decades as the climate continues to warm (Morin et al. 2009). Many temperate tree species will show large advances in leaf out at higher latitudes, including the northern United States and Canada. Delays in leaf out, or abnormal leaf-out events, could occur at the southern end of species ranges in the southern United States for some species including black ash {Fraxinus nigra] and sugar maple if those species fail to meet their winter chilling requirement. Species with photoperiod requirements are also unlikely to continue to show linear advancements in leaf-out dates with increasing temperatures since photoperiod will not change. Because there are a host of complicated fac- tors involved in leaf-out phenology, it is hard to predict whether leaf out will continue to advance linearly with changes in tempera- ture at the whole forest level. The possibil- ity of shifts in speeies composition resulting from climate change, as some species expand their range and others contract theirs, adds yet another layer of uncertainty to the prediction of leaf-out dates. If certain early successional species with minimal photoperiod and chilling requirements continue to leaf earlier in the spring, they may increase their abundance and distribution to become the dominant species, and shift the leaf-out time of the whole forest. The unmet chilling and photoperiod require- ments of other species may significantly slow the advance of leaf out at the whole forest level. These two scenarios have consequences for many ecosystem processes, including the uptake of carbon dioxide, tree growth, forest temperature, and water movement. The earlier leaf-out times of many escaped ornamental shrubs, such as lapanese barberry and several honeysuckle species, may help to explain why these species are increasing so greatly in abundance in our forests. Their ear- lier leaf-out times may give them a competi- tive advantage over native species with more restrictive requirements for leaf out (Willis et al. 2010). Ecological interactions The onset of spring affects not only plants and ecosystem processes, but also organisms that depend on those plants. Leaf-out timing deter- mines the availability of food and shelter for many species, particularly insects. This timing is especially important for species that have gone through a long winter with little avail- able food, or for bird species completing an energy-demanding migration north. From his close observations of nature in Concord, Fienry David Thoreau was aware of the ecological importance of the emergence of leaves in the spring, writing in 1854: "To-day the air is full of birds; they attend the opening of the buds. The trees begin to leaf, and the leaf-like wings of birds are in the air. The buds start, then the insects, and then the birds." Thoreau was aware of order of events based on what he had experienced in previous years and took for granted that the same pattern would persist, even with the large inter-annual varia- tion in weather. In the twenty-first century, we can no longer take for granted that this order of natural events will continue each year. While plants are responsive to changes in tempera- ture, other organisms that interact with plants Leaf -out Dates 21 ^ < Clockwise from top left: Photos of the Old North Bridge in Concord, Massachusetts, showing the development of the leaf canopy in the spring of 2010 (April 15, April 20, May 3, May 13). The meadow in the foreground is flooded in the first two photos, and dried out in the second two photos. in an ecosystem may not be quite so quick to respond. For instance, while certain species of birds arrive earlier in warmer years, other birds do not change their arrival dates, and some spe- cies are even arriving later (Miller-Rushing et al. 2008). Insects are involved also: If certain kinds of insects feed only on the young leaves of a particular plant species that are present for a limited time in the spring, those insect species may decline in abundance if they emerge too early or late in the spring relative to their food resource. Birds that depend on those insects for food may similarly decline in abundance. Much more work is needed to understand how climate change and rising carbon dioxide con- centrations are affecting ecosystem processes. If trees are leafing out earlier in the spring and dropping their leaves later in the autumn, they are likely increasing the net amount of carhon being sequestered in biomass. This possibility is supported by the work done by Andrew Rich- ardson and others at the Harvard Forest and the Howland Forest in Maine, showing that the earlier onset of spring in New England results in an increase of carbon sequestered in decid- uous forest and somewhat less in coniferous forest (Richardson et al. 2009b). If this is occur- ring over a large area and over many years, the longer growing season could allow temperate forests to withdraw more carbon dioxide from the atmosphere. The longer growing season and warmer temperatures could also mean that 22 Arnoldia 68/4 trees are losing more water vapor to the atmo- sphere during the process of photosynthesis; in consequence, forest ecosystems could possibly release less water to streams and aquifers, with major implications for drinking water supplies, flood control, and ecology of aquatic organisms. Conclusion Throughout the world, forests are being altered in many ways by the rising temperatures associ- ated with global climate change, and the earlier leaf-out dates of trees and shrubs is one such example. Earlier leaf-out dates are expected to continue in coming decades across much of North America. Over a longer period of time, many tree species will likely be extirpated on a local scale and shift their ranges in response to the changing climate. Because there is a wide variation among species in leaf-out times, changes in the species composition of a forest will also mean changes in leaf-out dates at the level of the whole forest. Disentangling the sep- arate effects of changing species composition and changing climate is one of the great chal- lenges of detecting leaf-out trends using remote sensing. Botanical gardens such as the Arnold Arboretum can contribute to these efforts by quantifying the differences among species in leaf-out dates for trees, shrubs, and vines all growing at one location, which for many spe- cies is outside of their native range. Such infor- mation can then aid in calibrating leaf-out dates over a large area using remote sensing. References Bradley, N. L., A. C. Leopold, 1. Ross, and W. Huffaker. 1999. Phenological changes reflect climate change in Wisconsin. Proceedings of the National Academy of Sciences of the United States of America 96; 9701-9704. Fisher, f. I., ). F. Mustard, and M. A. Vadeboncoeur. 2006. Green leaf phenology at Landsat resolution: Scaling from the field to the satellite. Remote Sensing of Environment 100: 263-279. Fisher, J.I. and I.F. Mustard. 2007. Cross-scalar satellite phenology from ground, Landsat, and MODIS data. Remote Sensing of Environment 109: 261-273. Gu, L., P. ). Hanson, W. Mac Post, D. P. Kaiser, R. Yang, R. Nemani, S. G. Pallardy et al. 2008. The 2007 eastern US spring freezes: Increased cold damage in a warming world? Bioscience 58: 253-262. Hunter, A. F., and M. J. Lechowicz. 1992. Predicting the timing of budburst in temperate trees, fournal of Applied Ecology 29: 597-604. Ibanez, I., R. B. Primack, A, [. Miller-Rushing, E. Ellwood, H. Higuchi, S. D. Lee, H. Kobori et al. 2010. Forecasting phenology under global warming. Philosophical Transactions of the Royal Society B Biological Sciences 365; 3247-3260. Korner, C., and D. Basler. 2010. Phenology under global warming. Science 317: 1461-1462. Lechowicz, M. I. 1984. Why do temperate deciduous trees leaf out at different times? Adaptations and ecology of forest communities. American Naturalist 124: 821-842. Menzel, A. 2000. Trends in phenological phases in Europe between 1951 and 1996. International Journal of Biometeorology 44: 76-81 . Miller-Rushing, A. L, T. L. Lloyd-Evans, R. B. Primack, and P. Satzinger. 2008. Bird migration times, climate change, and changing population sizes. Global Change Biology 14: 1959-1972. Miller-Rushing, A. f., and R. B. Primack. 2008. Global warming and flowering times in Thoreau's concord: A community perspective. Ecology 89:332-341. Morin, X., M. 1. Lechowicz, C. Augspurger, I. O’ Keefe, D. Viner, and 1. Chuine. 2009. Leaf phenolog>' in 22 North American tree species during the 21st century. Global Change Biology 15: 961-975. O'Keefe 1. 2010. Phenology of Woody Species. Harvard Forest Data Archive: HF003. Perry, T. O. 1971, Dormancy of trees in winter. Science 171; 29-36. Richardson, A. D., A. S. Bailey, E. G. Denny, C. W. Martin, and I. O'Keefe. 2006. Phenology of a northern hardwood forest canopy. Global Change Biology' 12: 1174-1188. Richardson, A. D., B. H. Braswell, D. Y. Hollinger, L P. Jenkins, and S. V. Ollinger. 2009a. Near-surface remote sensing of spatial and temporal variation in canopy phenology. Ecological Applications 19: 1417-1428. Richardson, A. D., D. Y. Hollinger, D. B. Dail, ]. T. Lee, L W. Munger, and I. O'Keefe. 2009b. Influence of spring phenology on seasonal and annual carbon balance in two contrasting New England forests. Tree Physiology 29: 321-031. Willis, C. G., B. R. Ruhfel, R. B. Primack, A. I. Miller- Rushing, L B. Losos, and C. C. Davis. 2010. Favorable Climate Change Response Explains Non-Native Species' Success in Thoreau’s Woods. PLoS ONE 5(1); e8878. doi:10.1371/ journal. pone. 0008878. Caroline Polgar is a graduate student at Boston University, where Richard Primack is a professor. For the past eight years, Richard Primack and his students have been investigating the impact of climate change on the plants and animals of Massachusetts, with much of the focus at the Arnold Arboretum and Concord. Not-So-Traditional Chinese Medicine: The Example of Donglingcao (Isodon rubescens) Eric S. J. Harris T he use of plants in Tra- ditional Chinese Medi- cine (TCM) has a long and well-recorded history. Not all plants in the TCM phar- macopoeia share this long history of use, however, and TCM, like any institution of knowledge, continues to grow, expand, and change. As an example, the medicines sold in TCM stores in Chinatowns in the United States include a mix of herbs that have been known for centuries, and some that have been intro- duced to the TCM pharma- copoeia only in the last few decades. This article provides the context for my research on one of those recent intro- ductions to the TCM pharma- copoeia: an unassuming yet potentially medicinally pow- erful herb in the mint family called donglingcao. Folk Medicines and Formal TCM A statue of Shennong ("The Divine Farmer’') on the campus of the Shanghai Univ sity of Traditional Chinese Medicine. (.\ll photos by the author) One of the earliest written works about botanical medi- cines in TCM is the Divine Farmer’s Materia Medica [Shen Nong Ben Cao ling] which was written over 2,000 years ago and catalogues more than 300 types of medi- cines, most of which are plants (Yang 1998). The book has been attributed to the mythical Shennong (the Divine Farmer) who is claimed to have tasted different plants himself to deter- mine which were poisonous and which could be used as medicine. Many, if not all, of the herbs listed in the Divine Farmer’s Materia Medica remain in use. For example, the book includes herbs such as ginseng [Panax ginseng), licorice [Glycyrrhiza uralensis), and goji berries [Lycium chinense). While works such as the Divine Farmer’s Materia Medica maintain an influence in for- mal TCM practice, the use of different botani- cal medicines in China continues to transform 24 Arnoldio 68/4 and grow. For example, the recently published multi-volume work of the Chinese Materia Medica (Ministry of State Administration of Traditional Chinese Medicine 1999) lists more than 9,000 different medicines, or roughly 30 times as many substances as listed in the Divine Fanner’s Materia Medica. The Chinese Materia Medica contains different substances, such as animals and minerals, but plants make up the overwhelming majority. The Chinese Materia Medica includes plants that have been in recorded use in China for hundreds of years, and also those that were incorporated only very recently. Of the latter, a large num- ber of the newly recorded botanical medicines were catalogued for the first time in the 1960s and 1970s under Chairman Mao's directions to develop and improve medicine in the Chinese countryside. One result of those efforts was the documentation of plants used as folk med- icines (in Chinese, caoyao] (Harris and Yang 2009). Folk botanical medicines are typically used in a limited area in China (e.g., within one province), are generally not accompanied by pharmacy in a Traditional Chinese Medicine hospital in Beijing. Each wooden drawer holds 2 to 3 different medi- cines, most of which are plants. Traditional Chinese Medicine 25 Native range of Isodon rubescens by province (shaded in dark green), according to the Flora of China (Li and Hedges 1994). Region of traditional medicinal use of 1. rubescens circled in yellow dashed line. Collection sites from field trip in 2009 indicated by red triangles. Yellow River shown in blue. written documentation, and information about their medicinal uses is passed down orally from generation to generation. Folk botanical medi- cines can be distinguished from formal TCM herbs (in Chinese, zhongyao). Formal TCM herbs typically have a much longer written his- tory, standards for their production and use, are often cultivated, and are well known through- out China. Ginseng, licorice, and goji berries are good examples of these. In general, formal TCM herbs are listed in the official Pharmacopoeia of the People’s Republic of China (Chinese Phar- macopoeia Commission 2005). By contrast, folk medicines are not standardized and are usually collected from the wild. There are many exam- ples of folk medicines from throughout China, but one of recent note is the herb donglingcao {Isodon rubescens). The Story of Donglingcao Donglingcao {Isodon rubescens) is a mint fam- ily (Lamiaceae) plant within the basils and allies group (Tribe Ocimeae) and is closely related to plants like lavender {Lavandula) and coleus {Solenostemon). The genus Isodon includes about 100 species, most of which occur in Asia, with a few species in Africa (Li and Hedges 1994). Isodon rubescens is distributed through- out central China, usually in dry areas on slopes or in thickets along streams. The area of tradi- 26 Arnoldio 6H/4 Clockwise from upper left: Images of Isodon rubescens — a plant growing in typical habitat, a group of plants in flower, close-up view of flowers, inflorescence structure. tional medicinal use of the plant is in the Tai- hang Mountain range near the Yellow River in Northern Henan province. Plants of I. rubescens are shrubs that can grow about 1 meter (3.3 feet) tall. They typi- cally have many sprawling branches with ovate leaves (Li and Hedges 1994). Isodon rubescens flowers from late summer into autumn with inflorescences of small (about 1 cm[.4 inches] long) white or purplish flowers. Interestingly, populations of /. rubescens growing in parts of China that experience sub- freezing temperatures can sometimes produce ribbons of ice — known as "ice flowers" — from the stem (Means 2003). In fact, the Chinese name donglingcao ( ^ 'Vi ) roughly translates Traditional Chinese Medicine 17 as "winter-ice herb," probably in reference to this phenomenon. Based on the tolerance of the plant to low temperatures, it is possible that donglingcao would be able to grow in gardens in New England. I have not seen it grown here yet, but curious gardeners who would like to try growing it may find seeds of /. nibescens available commercially from some distributors in the United States. The first written records of the medicinal use of donglingcao in China are from the 1960s and 1970s during the period of documentation of China's folk medicines. The plant has been traditionally used for indications such as sore throat and stomach problems. Donglingcao is usually collected in the wild, although there have been some recent efforts at cultivation in northern Henan province. To prepare donglingcao as a medicine, the aerial portions (i.e., stems and leaves) are col- lected in July and August and dried in the sun. When needed, the dried plant is usually steeped in water to make a tea. The taste of the tea is extremely bitter, owing to diterpenoid chemi- cals produced by the plant (more about those below). In fact, it is very easy to identify plants of Isodon in the field by simply tasting a leaf — if after several bites the bitter taste compels you to spit it out, then the plant is likely a spe- cies of Isodon. In addition to being taken as a tea, donglingcao has been combined with other herbs in some Chinese patent or proprietary medicines that are available in pill form. During the effort to study folk botanical med- icines in the 1970s, it was discovered that one of the bitter diterpenoids in donglingcao, a chemi- cal called oridonin, might have some use in treating cancer (Sun et al. 2006); interestingly, parallel work in Japan on related species of Iso- don, such as I. japonicus also came to similar results. This discovery followed the general inte- gration of scientific and chemical approaches in the research of Chinese herbs (in what might be called a "re-tooling" of Shennong's approach). A Donglingcao cultivation site in northern Henan province. The plants shown are usually larger in the wild, but this picture was taken in late October after the plants had already been harvested. 28 Arnoldio 68/4 Commercial products that contain donglingcao include (left to right) throat lozenges, pills, and tea. Oridonin, one of the main chemical ingredients respon- sible for the bioactivity of donglingcao. famous example of the fruits of these efforts is the anti-malarial compound artemisinin. Arte- misinin was originally discovered in the 1970s hy Chinese researchers examining Artemisia annua, a plant long known in TCM (Hsu 2006). Artemisinin is now used globally as a standard treatment for malaria, and cultivated plants of Artemisia annua remain the main source of the compound today. In contrast to the more popu- lar Artemisia, donglingcao and the chemical oridonin gradually lost the spotlight after the initial studies in the 1970s. However, in the last few years oridonin has again garnered scientific interest for its potential as an anti-cancer rem- edy (Zhou et al. 2007). Current Research Starting in 2009, I became interested in donglingcao as an example of a folk botanical medicine that had clear potential to become a standardized TCM herb with more common and widespread use. I began research on this plant to understand the evolution and ecology of the chemicals that are responsible for the medicinal effect, in particular the compound oridonin. The primary goal of this research was to suggest populations or related species of this plant that would have the highest production of oridonin. In collaboration with researchers in the colleges of Chinese medicine in Beijing and Henan province, I traveled to China in the fall of 2009 to collect plants of I. rubescens and related species. The trip included collection areas in Henan province where donglingcao is traditionally used and also other areas in China where I. rubescens is known to occur (Hubei and Guizhou provinces). Through the course of the collecting trip, I traveled together with a Chinese graduate stu- Traditional Chinese Medicine 29 dent by car, sleeper-train, bus, and taxi, covering a distance of more than 1,500 kilometers (over 900 miles) from the northernmost col- lection site to the southern- most site (roughly the same distance as between Boston and Chicago). This distance allowed me to visit various scenic rural areas, from the expansive Taihang Moun- tains to small ethnic minor- ity villages in Guizhou province. The collection trip also provided the oppor- tunity to sample a wide vari- ety of Chinese local cooking, from mutton noodle soup in Henan in the north to fried "field chicken" (=frog) in the south. At each collection site, I collected several individual plants of Isodon to account for possible variability of chemical production within populations. For each indi- vidual plant, I collected a pressed voucher specimen, dried leaves in silica desic- cant, and a seed sample if the plant was in fruit. The vouchers will be accessioned and deposited at the Har- vard University Herbaria. The dried tissue in desic- cant has been used for DNA and chemical analyses. The seeds were collected so that chemical content of all populations could be compared in greenhouse grown samples in order to factor out possible differences in chemical production that result from different growing environments. I have completed the chemical and genetic lab work on the wild-collected and greenhouse-grown samples and am now eagerly examining and interpreting the results. In addition to my primary goal of locating sources of high oridonin production, the results Environment near Isodon collection site in the Taihang mountains, Henan province. Environment near Isodon collection site in [i^ngkou county, Guizhou province. of my work will provide insight into the degree of variability in oridonin production in I. rube- scens and related species, and will ideally help in the standardization of the use of the plant for more widespread use in TCM and elsewhere. In fact, although previous editions of the Pharma- copoeia of the People’s Republic of China did not list donglingcao, the most recent edition released in the summer of 2010 now includes this plant. It is likely, then, that research and .^0 Arnohlid (iH/4 The author in a thicket of Isodon rubescens in Hubei province. development of this plant will continue. With roots as a folk medicine in China, donglingcao has seemingly finally earned its place in the canons of the official Traditional Chinese Medi- cine. And, depending on the plant's hardiness and desirability as an ornamental, it may also earn its place in gardens in New England. [NOTE: Some of the greenhouse-grown Iso- don rubescens plants from this collection trip will he planted at the Arnold Arhoretum within the next year or two.] References Chinese Pharmacopoeia Commission. 200.S. Phaimacopoeia of the People’s Republic of Chino: 2005. People's Medical Publishing House, Beijing. Harris, E. and R. Yang. 2009. Variation and Standardization in the Use of a Chinese Medicinal Moss. Economic Botany 65: 190-20.T Hsu, E. 2006. Reflections on the "discovery" of the antimalarial qinghao. British loiirnal Of Clinical Pharmacology 61: 666-670. El, X.W. and EC. Hedges. 1994. Isodon. In: Flora of China. Vol. 17, 269-291. Science Press Missouri Botanical Garden, Beijing & St. Louis. Means, B. 2005. Mysterious Ice "Flowers". The American Gardener lan/Feb: 34-37. Ministry of State Administration of Traditional Chinese Medicine. 1999. Chinese Materia Medico. Shanghai Science and Technology Press, Shanghai. In Chinese. Sun, H., S. Huang, and Q. Han. 2006. Diterpenoids from Isodon species and their biological activities. Natural Product Reports 23: 673-698. Yang, S. 1998. The divine farmer’s materia medico : a translation of the Shen Nong Ben Cao ling. 1st ed. Blue Poppy Press, Boulder CO. Zhou, G., S. Chen, Z. Wang, and Z. Chen. 2007. Back to the future of oridonin: again, compound from medicinal herb shows potent antileukemia efficacies in vitro and in vivo. Cell Research 17: 274-276. Eric S. I. Harris, PhD, is a Research Associate at the Harvard University Herbaria. 2010 Weather at the Arboretum Bob Famiglietti A s in 2008 and 2009, above average rainfall continued in 2010. Moisture combined with warm temperatures and plentiful sunshine created optimum growing conditions for the Arboretum's plant collection. JANUARY produced less than 6 inches of snow and was relatively mild. The average temperature was almost 5°F warmer than the previous January. A January thaw occurred on the 24th through the 28th, reaching the monthly high temperature of 57°F on the 26th. It dropped to single digits on only three nights, a rare occurrence, reaching a low of 5°F each time. The first Arctic cold front of the year passed through on the 29th with wind gusts up to around 50 mph. The 6-inch snowpack dwindled to a trace by month's end. FEBRUARY was mild and had 4.74 inches of precipitation, much of it falling as rain. The 24th, 25th, and 26th produced strong east winds and 3.88 inches of rain. A low of 13°F was recorded on the 7th, one of the highest lows ever recorded for February. The remainder of the month was unseasonably warm and a high of 49°F was reached on the 21st. Snowfall was light with only 5 inches recorded from two storms. A minimal snowpack created optimum ground conditions, enabling our horticulture staff to perform vital winter pruning of the Arboretum's plants. There was only a trace of snow on the ground by the end of the month. MARCH continued the 2010 pattern of mild temperatures. There was only 0.4 inch of snow for the month. Spring appeared to be on a very early track and, as good gardeners, we hoped for the arrival of abundant spring rains. By month's end — and nearly 18 inches of rain later — we regretted what we had wished for. March started mild with strong winds, rain, and a trace of snow. Temperatures raced into the 50s for five days by mid-month. A three-day Nor'easter produced 3.94 inches of rain on the 14th, 3.74 inches on the 15th, and 1.27 inches on the 16th. A total of 9.43 inches of rain had fallen by mid- month. The rain continued: another 1.51 inches on the 23rd, 0.85 inches on the 24th, with smaller amounts from the 26th through the 29th. The third large storm of the month arrived on the 30th, dropping 3.15 inches that day and 2.15 inches on the 31st, ending the month with an amazing 17.44 inches of precipitation. This was about 13 inches above normal. There were 16 days with measurable precipitation in our rain gauge. March became the wettest month measured at the Arboretum since the weather station was established at the Dana Greenhouses in 1962. (By comparison, the wettest month ever recorded for Boston's official weather site was 1 7.09 inches in August 1955.) All the rain caused numerous problems throughout the Arboretum: ponds overflowed their banks and flooded adjoining roads and collections, the linden ■March 15th — Heavy raintall caused Bussey Brook to overflow, lead- ing to serious erosion in several locations including this spot at the base of Hemlock Hill near the South Street Gate, (matt connelly] V'isitors walked along a narrow dry strip on Forest Hills Road on March 16th, with an overflowing Daw'son Pond in the background. (KEVIN B. SCHOFIELD) Arboretum horticultural technologist Kit Ganshatv measures water depth in Rehder Pond on March 25th after yet more rain fell on the previous two days, (.nancy rose) [Tiliti] collection looked like a large lake, and Bussey and Gold- smith Brooks overflowed their banks, causing severe erosion. Our secondary road system was severely eroded — 90% of it had to be regraded and resurfaced, and additional water mitigation channels had to be installed. In early April a sinkhole was dis- covered in the road surface over Goldsmith Brook at the Arbo- retum's main entrance, likely caused when March floodwaters deteriorated the underlying cul- vert. The entrance was closed to vehicle traffic for nearly a year hut re-opened on April 1, 2011. APRIL started warm, reaching 78°F on the 3rd. It reached 90°F on the 7th, breaking a record as the earliest 90°F day in April. A low of 32°F occurred on the 28th. It was the only freezing tempera- ture recorded for the month — a rare event — and the last frost date for the season. April ended on the dry side with no snow and only 2.13 inches of rain. This gave our nurseries a chance to dry out so our spring transplant- ing season could begin. MAY was warm, dry, and sunny. A high of 94'F on the 26th and one of the sunniest Mays on record helped push the aver- age high temperature over 4‘F above normal, ranking it the 5th warmest on record. The first five months of 2010 averaged over 3°F above normal. Precipi- tation was below normal at 2.92 inches. Lilac Sunday on May 9th was partly sunny but cool and very windy. Weather 33 Arnold Arboretum Weather Station Data • 2010 Avg. Avg. Avg. Max. Min. Precipi- Snow- Max. Min. Temp. Temp. Temp. tation fall (°F) (°F) (°F) (°F) (°F) (inches) (inches) JAN 35.2 20.1 27.7 57 5 3.74 5.3 FEB 37.2 24.3 30.8 49 5 4.74 5.0 MAR 50.3 35.2 42.8 72 24 17.44 .4 APR 61.6 42.1 51.9 90 32 2.13 MAY 73.1 52.0 62.6 94 38 2.92 JUN 79.6 60.7 70.2 93 49 3.52 JUL 86.2 68.0 77.1 98 54 2.63 AUG 81.4 62.7 72.1 92 52 8.05 SEP 77.2 57.1 67.2 95 45 1.99 OCT 62.8 44.0 53.4 82 33 5.42 NOV 51.5 34.0 42.8 65 25 3.75 DEC 37.5 23.4 30.5 56 12 3.93 16.1 Average Maximum Temperature 61.1°F Average Minimum Temperature 43.6°F Average Temperature 52.4°F Total Precipitation 60.26 inches Total Snowfall 26.8 inches Warmest Temperature 98°F on July 7 Coldest Temperature 5°F on January 5 and February 1 Last Frost Date 32°F on April 28 First Frost Date 29°F on November 1 Growing Season 186 days 34 Arnoldio 68/4 JUNE continued very warm, reaching 93°F on the 24th and 28th. It was the 15th warmest June in Boston's 139 years of weather record keeping. In contrast, June 2009 was the 3rd coldest. There were 17 days of measurable ram hut only 3.52 inches fell for the month. Thunder was detected on six days, double the average. JULY was very hot and somewhat dry. The average high temperature was 86.2°F, making it the 3rd hottest July on record. It reached 100°F at Logan Airport in Boston for the first time since 2002. It hit at least 90°F twelve times this month alone, marking 17 days already for this year, more than the entire annual average for Boston. We had three heat waves (highs of at least 90°F for 3 consecutive days) this month. An Arboretum high of 98°F was reached on the 6th. In contrast, last June-Iuly was the 4th coldest in the 138 years of Boston's weather records. Rain totaled 2.63 inches, in contrast to last July's nearly 8 inches. AUGUST kept pace with the preceding months as warmer than normal, though not as extreme as July. A high of 92°F occurred on the 9th. This sum- mer (June-August) was the third warmest on record. It was also a wet month as 8.05 inches of rain fell, though rainfall occurred on only eight days. 6.43 inches of rain fell on the 22nd through the 26th. Three 90°F days ended the month as another heat wave began. SEPTEMBER also was very warm and dry with only 1 .99 inches of rain. Our only thunderstorm occurred on the 8th. The month started as August had ended with temperatures in the 90s for the first three days. A high for the month of 95°F was reached on the 2nd. This was the third warmest Septem- ber on record. Wind gusted to nearly 50 mph on the 30th as Tropical Storm Nicole passed offshore. OCTOBER was on track with the preceding 9 months as we continued with above average temperatures. A high of 82°F was reached on the 1st, our last reading in the 80s for the year. Decent rainfall occurred with a total of 5.42 inches recorded. Precipitation was recorded on 14 days hut the remaining ones were often sunny and glorious. There was no trace of snow this month but a low of 33°F was recorded on the 22nd, bringing just a hint of light frost in the low areas around the Arboretum ponds. This spectacular month of weather made for grand viewing of our fall foliage. NOVEMBER became our first colder than normal month of 2010. The Arboretum's first freeze occurred the night of the 1st when temperatures dropped to 29°F, ending our growing season. A heavy widespread frost occurred on the 3rd. Rainfall was near normal with 3.75 inches. There was no trace of snow this month, and a high of 65°F was recorded on the 17th. Finally as temperatures cooled we sensed the impending dormant season, a prerequisite to winter storage of our containerized plant material from the Dana Greenhouses. Weather 35 Glowing orange and gold sugar maple [Acer saccharum) foliage framed the Leventritt Shrub and Vine Garden on October 25th (MICHAEL DOSMANn) DECEMBER was snowy and the only month of 2010 with markedly below normal temperatures. A low of 12°F was reached on the 10th and then a high of 56°F was recorded on the 13th, an extreme range of 44°F in three days. Our first snowfall occurred on the 21st, leaving 2 inches on the ground. There was a large, violent Nor'easter on the 26th and 27th. Over a foot of snow was deposited but blizzard-level wind conditions created snowdrifts 3 to 4 feet deep, making it difficult to measure exactly how much snow fell. This fierce storm left some of the Arboretum's plants with structural damage. The year ended with a snow depth of nearly 1 foot, a sign of things to come. Bob Famiglietti is a Horticultural Technologist at the Arnold Arboretum's Dana Greenhouses. The Family Tree: Prunus 'Hally Jolivette' Miles Sax A sk someone to show you their family tree and you'll likely be shown a gene- alogy chart in an old book, or perhaps a family lineage document on the computer. As a child, if I asked my father to see our family tree he would take my hand, lead me outside, and show me the enchanting spring blooms of the 'Hally Jolivette' cherry in our yard. This tree — named for my great-grandmother — is important to me both as a link to my family history- and as a horticultural gem. Prunus 'Hally Jolivette' is a flowering cherry hybridized by Dr. Karl Sax, the Arnold Arbore- tum's fifth director (and my great-grandfather). A research scientist by training. Sax's investi- gations in genetics and chromosome studies played a seminal role in the biological sci- ences of his time, most notably in the field of cytology. His interests also encompassed plant breeding, a field to which he made many con- tributions through his extensive hybridizing studies. Conducting much of his work while a professor at the neighboring Bussey Institute, many of Sax's hybrids "jumped the fence" and ended up in the Arboretum's collections, and a number were introduced to the nursery trade. Perhaps the best of Sax's hybrids, Prunus 'Hally Jolivette' was introduced by the Arnold Arboretum in 1948. It resulted from crossing P. suhhirtella and P. x yedoensis, and then back- crossing with P. subhirtella. It is a fine-textured, densely branched, rounded small tree or large shrub that grows about 15 feet (4.6 meters) tall and equally wide. Each spring it delights the eye with a profusion of pink buds opening up to IV-i inch (3.2 centimeter) diameter pinkish white double flowers. At the Arboretum, flow- ering occurs in late April or early May. Bloom may continue for ten to twenty days, a nota- bly long period for a flowering cherry. Flowers open prior to leaf emergence so the floral effect is unobscured. The 2 to 3 inch (5.1 to 7.6 cen- timeter) long leaves are simple, alternate, and dark green. 'Hally Jolivette' cherry grows best in full sun, is drought tolerant, and is an ideal plant for small gardens, specimen plant- ings, or even bonsai. Best adapted to USDA zones 5 through 7, this cherry is a precocious bloomer and often flowers in its second year of growth. Three young specimens (acces- sions 278-2007-B, C, and D) can be seen in the Arboretum's newly renovated Bradley Rosaceous Collection. Prunus 'Hally Jolivette' has received many accolades .including awards from both the Pennsylvania Horticultural Society and Cor- nell Cooperative Extension. Of his many intro- ductions, Karl Sax clearly held this Prunus in a special place because he named it in honor of his wife, colleague, and scientist in her own right. Dr. Hally Jolivette. She was a mycologist and botanist, and in 1912 was the first woman to receive a Ph.D from Stanford University in the field of botany. She held many academic posts across the country including instruc- torships at Washington State University, Wellesley College, and the Bussey Institute. She was a research scientist and published original work as well as co-authoring many papers with Dr. Karl Sax. Both a scientist and a devoted mother, she is remembered as a woman who put cookies on the table for her three children one minute and was deep in study with her microscope the next. My family has been honored and delighted to have this tree that not only greets each spring with great beauty but also reminds us of our lineage. In the words of plantsman Michael Dirr "Great plants transcend the generations," and with this in mind I hope that Prunus 'Hally Jolivette' will be planted and enjoyed for many years to come. Miles Sax is a horticultural apprentice at the Arnold Arboretum, where he works on evaluating, maintaining, and improving the Malus collection.