Black Locust Savanna at Iron Bridge Prairie

Black Locust savanna

The savannas in the prairie region mainly consist of Bur Oak, Quercus macrocarpa, but here at the Iron Bridge Prairie at Midewin it is a small savanna or rather open woodland of Black Locust, Robinia pseudoacasia.

The Black Locust is a lovely tree with ornamental branches and a open, loose crown with a scanty leafage that allow some light to pass to the ground and permit a rich understory of grasses and forbs.

The Iron Bridge Prairie at Midewin is fairly new. The restoration of the prairie that once existed here began as late as in 2009. This text is partly taken from an information sign at the prairie. Thanks to many years of cultivating rowcrops as corn and soybeans the soil was rather free from weeds.

Two years ago Midewin staff and volunteers spread 1000 pounds of prairie seeds from 98 different species. This was followed by the planting of 5000 prairie plant plugs.

The first plants to flower are the pioneer plants with rapid growth as Yellow Coneflower, Ratibida pinnata and Wild Bergamot, Monarda fistulosa. They benefit from disturbance and have their best development some few years afterwards.

It will take several years for the majority of the prairie plants to establish their root systems and grow in numbers to out-compete invasive, weedy species.

 

Like a yellow lake of Coneflowers

Monarda and Ratibida are pioneer members of the prairie ecosystem 

Monarda fistulosa, Ratibida pinnata and Coreopsis tripterris

The path through the Black Locust Savanna

The Yellow Coneflower rules in Laholm

Yellow Coneflower, Ratibida pinnata, at the savanna in Laholm

Last weekend I first visited the plantings in the city park of Laholm and then continued to the Prairie Junction in Mariestad. That is a prairie planting we are making together with the garden students at the DaCapo School belonging to the University of Gothenburg. Today it is 1 500 sqm in size, but already next month we'll plant another additional 500 sqm.

Here are some pictures from the savanna in Laholm to start with. This time of the year there are many different species in bloom, but the dominating plants now are the Yellow Coneflower, Ratibida pinnata, and Coreopsis lanceolata.

Echinacea purpurea, Coreopsis and Ratibida

Smoke on the Savanna

Geum triflorum in the beginning of the smoke stage

In the end of May the students at the course in garden design at the University in Alnarp visited the new plantings in the city park of Laholm. The savanna has its best development during summer and early autumn with a beautiful display of Coneflowers, Echinacea and Ratibida, and of course all colorful grasses.

At this time of the year some parts of the savanna are dominated by the Prairie Smoke, Geum triflorum. It is a delicious little plant with deep brownish red flowers followed by mauve seed heads resembling soft, smoky feathers. The plant is creeping slowly by runners and will build up small colonies after some few years. Hopefully they will also be able to spread by seeds.

There are some other plants at the savanna in bloom during late May and early June and the brightest among them is the Golden Alexanders, Zizia aurea. The Canadian Columbine, Aquilegia canadensis is already coloring the savanna red, soon also the flax open its pale blue flowers and then the early summer blooming has started.

Prairie Smoke, Geum triflorum

Zizia aurea is flowering in May at the savanna in Laholm

The Canadian Columbine has hanging flowers in red and yellow

The Honey Locust Savanna

In 2008 we created two biotope plantings in the city park of Laholm inspired by the biomes from North Eastern North America. The Honey Locust Savanna with sparse groves of trees and a understory of savanna and prairie forbs is located on a west facing slope in the park.

Linum perenne and Coreopsis lanceolata

Penstemon smalli and Coreopsis lanceolata

All pictures above are from last year, 2009

This year the flax is overwhelming