Silva Fennica vol. 2 | 1968

This article is a book review of a book ’Marktforschung und Gemeinschaftwerbung für die Forst- und Holzirtschaft. Methoden, Vorschläge udn Beispiele’ by Michel Becker.

• Juslin, E-mail: hj@mm.unknown

This article is a book review of a book ’Produksjon av skogspanter’ by Rusten, Arne and Landmark, Leif.

• Yli-Vakkuri, E-mail: py@mm.unknown

This article is a book review of a book ’World pulpwood’ by Thorsten Streyffert.

• Keltikangas, E-mail: mk@mm.unknown

The concept of the internal rate can be defined as the rate of interest, which if applied to expenditures incurred at different times, gives a compounded sum equal to revenues compounded at the same rate for the same time. This concept has long been used in forestry, particularly concerning the development of a stand, because in this case there is a time difference between many items of expenditure and revenue. Several terms have been used or the notions derived on this basis. The term internal rate of return has begun to appear only recently. This article explains different variations of the concept and its different names, together with some related concepts and terms.

The PDF includes a summary in English.

• Saari, E-mail: es@mm.unknown

In early spring 1968 it was noticed that the black grouses (Lyrurus tetris L.) was eating terminal shoots of Scots pine (Pinus sylvestris L.) seedlings in a tree nursery in Luumäki, Southern Finland. The terminal shoots were picked 1–4 cm from the top of the seedlings. In total some thousands of two-year-old seedlings were damaged. The depth of the snow was 10–15 cm deep and only the tops of the seedlings could be seen above the surface of the snow.

The PDF includes a summary in English.

• Löyttyniemi, E-mail: kl@mm.unknown

The article is a lectio praecursoria held on May 18, 1968 at the University of Helsinki. It deals with some aspects connected with the adaptation of mathematic-statistical methods and in particular with multivariate methods. Among these regression, factor, and principal-component analysis are mostly used by the Finnish forest economists.

The PDF includes a summary in English.

• Mäkelä, E-mail: jm@mm.unknown

18 permanent sample subplots of the Swedish and the Hassian Forestry Institute, each measured in equal intervals for several decades, were divided into subplots of different size. An analysis of variance was calculated for every set of subplot size. The development of intraclass-correlations over years and over different sizes of subplots could be explained if three different correlations were assumed: soil-correlation, correlations from irregular distribution of the trees, and correlation resulting from competition. Intraclass-correlations were positive or negative depending on dominance of one or two of these correlations.

An explanatory simultation study of competitional variance showed the effect of the degree of competitional correlations on the variance of means of subplots of different sizes. If this coefficient was small, all variances of subplots means within the range investigated became larger than expected in experiments without competition, with larger coefficients the variances of means of the smaller subplots became smaller, those of larger subplots larger than expected.

Plots of medium or large size are probably optimal for long term experiments with forest trees, if all sources of costs in such experiments are taken into account.

The PDF includes a summary in English and Finnish.

• Stern, E-mail: ks@mm.unknown

The winter food of moose (Alces alces L.) was examined in 1967-68 in the Saariselkä fell area in the communes of Inari and Sodankylä, in the northern parts of the communes of Salla and Savukoski, and in the central part of the commune of Salla in eastern Lapland in Finland.

In northern parts of Salla and Savukoski 25 moose were followed during 3.-13.4.1968. This area is typical wintering terrain of moose in north-east Lapland. According to the estimate, 45% food taken by the moose was Scots pine shoots and needles, 28% birch, 17% juniper sprigs and needles, 9% willow, and 1.5% bear moss. According to observations of the researchers in 26.1.-16.5.1968, moose seemed to avoid birch, even if it was available in the area, and eat Scots pine shoots and needles and juniper.

Moose seemed to prefer willow in as a winter feed in the southern part of the area studied, where it accounts according to the present and earlier studies 50-90% of the winter food. In the northern wintering areas of moose, where willow is not as common, willow seemed to account for less than 10% of the winter food. There Scots pine is the most important winter food for moose.

The PDF includes a summary in English.

• Pulliainen, E-mail: ep@mm.unknown
• Loisa, E-mail: kl@mm.unknown
• Pohjalainen, E-mail: tp@mm.unknown

The aim of this paper was that of studying the optimum growing schedules of forest stands, with the classic Faustmann formula as starting point. The study is mainly theoretical in nature. The study shows that the net present-value of the future revenues from a forest stand can be calculated, not only by means of the harvesting revenues, but also by a more theoretical concept, here termed the current gross soil rent. The current gross soil rent represents the difference between the current value growth and the rent of the growing stock.

By use of the concepts described here, it is theoretically possible to find the growing schedule for the stand which maximizes the net present-value of the stand. To make the formulae simpler, a one-year period has been adopted for discussion of the concepts involved in determination of the optimum structure and density of the growing stock, and the financial maturity. However, these concepts can be extended to cover periods of any length.

The method for determination of the optimum growing schedule for a forest stand can be summarized as follows: Thin the stand as the internal rate of return on the marginal increase in ’timber capital’ falls below the guiding rate of interest. Clear-cut and regenerate the stand as the internal rate of return on the sum of the ’timber and soil capital’ falls below the guiding rate of interest.

The PDF includes a summary in Finnish.

• Kilkki, E-mail: pk@mm.unknown

The aim of the present study was to describe the diffusion of the professional insight in forestry taking place among forest owners and as factors attached thereto. The material is based on interviews of 289 forest owners in municipalities of Jämsä and Karstula in Central Finland in 1966. The forest owners were a random sample of all males in the municipalities, who were in the possession of at least 2 ha of cultivated land and 10 ha of forest.

Mass media (papers, radio and television) was an important source of information for the forest owners. Forest educational events are specially planned to spread information on forestry to forest owners, but 40% told that they had never participated any such event. Only 8% had got professional forest education. Knowledge concerning forests and forest management may also be inherited from the forest owner’s parents, or in discussions with professional forest officers or neighbours. About 73% of the forest owners had been in touch with professional foresters at least once during the last three years.

A third of the forest owners regarded professional insight their most important source of information on forestry, a little smaller group considered instruction in forestry questions the most important source. The third largest group had achieved their knowledge on forestry on own experience and inherited knowledge. Forest owners favouring mass media, own experience and inherited knowledge were often owners of a small forest holding.

The PDF includes a summary in English.

• Järveläinen, E-mail: vj@mm.unknown
• Vadén, E-mail: tv@mm.unknown

The technical term reduced yield stands – sometimes reduced yield soils – is widely used in the Finnish forest literature. However, there is no clear definition of the notion reduced yield and no explanation of how this notion is measured in the classifications. Some committee reports and bill proposals and some laws and statutes use the reduced yield forest soil. No definition can be found. In my opinion the term reduced yield forest soils ought to be completely abolished until forest soil experts can perhaps define what it means, if they consider such a concept useful.

Explanations for the term reduced yield stands can be found in the descriptions of classification systems of stands. According to them, the criterion is partly silvicultural (site, species of tree), partly mensurational (volume, sometimes growth), partly economic. No explanation is found as to how the economic aspect is measured, nor about the limit of a full yield and reduced yield.

In my opinion such a term is confusing. I therefore suggest that the term reduced yield stand ought to be abolished. If something is needed instead, I suggest the term understocked stand, defined as a growing stock under certain percentage of a fully stocked stand. The notion of economic reduced yield cannot be generally tied to certain silvicultural and mensurational characteristics of stands. The economic aspect of certain kinds of stands may differ, depending on the owner of the forest and his economic situation, the location of the forest, the composition of the whole forest ownership unit, etc.

The PDF includes a summary in English.

• Saari, E-mail: es@mm.unknown

Eight Scots pine (Pinus sylvestris L.) seed sources, ranging from 42° to 66° north latitude, were grown under a constant, 16-hour photoperiod in a greenhouse for approximately 6 months. Rates of photosynthesis, as measured by an IRGA, and growth, as measured by increase in height and fresh and dry weight, differed among seed sources at the end of the six-month growing period. Photosynthetic capacity and growth were strongly related to latitude of seed source, and were greatest in the seed sources coming from a parent environment in which maximum photoperiods are about 16 hours.

Photosynthetic efficiency (rate of photosynthesis per gram needle weight) was also strongly related to latitude of seed source, but was lowest in the seedlings which exhibited the greatest growth and photosynthetic capacity. This may have been due to (1) more mutual shading of needles on the larger seedlings and (2) a lesser proportion of juvenile needles on the larger seedlings or (3) biochemical differences in the use of photosynthate in the needles. Seed source and light intensity had an interacting effect on rates of photosynthesis only in seedlings of the two northernmost seed sources.

The PDF includes a summary in Finnish.

• Gordon, E-mail: jg@mm.unknown
• Gatherum, E-mail: gg@mm.unknown

The present paper is a preliminary report of a project designed to determine the order of profitability of various forest improvement measures – seeding and planting, drainage, and fertilization – in various types of stands and in different parts of the country on drained peatlands. Sample plot data on the effect of draining on increment was derived from areas drained 28– 36 years ago. The study was carried out in the southern half of Finland.

The observations on increment changes are based on two measurements of the sample stands 12 years apart. Supplementary calculations indicate that the stands on drained peatland, depending on site quality and tree species, have either continued to grow like mineral-soil sites of similar fertility or have somewhat increased their growth rate.

The effect of draining intensity was studied using strip measurements. It was found that both the total amount of wood produced (current stand + cutting removal + natural removal) and the current annual volume increment for the 5-year period systematically decrease as the ditch interval increases. The decrease is, however, relatively slight. In Eriophorum vaginatum pine swamps, the total amount of wood produced and the increment show a decrease of ca. 20% with an increase in ditch interval from 20 to 60 metres. In other sites, the decrease is ca. 5-10%

It can be concluded that if the increase in ditch interval do not result in considerably poorer timber assortment distributions than indicates by stand production and increment, it is profitable to pan for a relatively large ditch interval and a slightly smaller than maximum wood production. Supplementary data and check calculations may cause some changes in these preliminary results.

The PDF includes a summary in English.

• Seppälä, E-mail: ks@mm.unknown

The time interval between final felling and plantation means a waste of time and thus a production loss, and may lead to lush growth of ground cover and hardwood sprouts, which increases expenses in forest management. The objective of this study was to determine the length of time between final felling and artificial regeneration in private forests in the forest districts of Uusimaa-Häme in Southern Finland and Pohjois-Häme in Central Finland. The material consists of a sample of 150 plans of the 952 cutting and regeneration plans in the district of Uusimaa-Häme and a sample of 140 plans of the 1,102 plans in Pohjois-Häme.

The time lag between final cutting and seeding or planting was on average 1.4 years in Pohjois-Häme district and 0.7 years in Uusimaa-Häme. In the latter district, 56% of the logged area was regenerated in the spring immediately following the cutting, and 84% not later than in the second spring. In Pohjois-Häme, 29% of the harvested area was regenerated immediately in the first spring following cutting, and 79% not later than in the third spring following cutting.

In Pohjois-Häme, the interval was shortest in the smallest forest holdings, and longest in the largest holdings with the largest regeneration areas. The length seems to depend mainly on the size of the regeneration area. In Uusimaa-Häme district, the interval was shortest in the smallest holdings, rather short in the largest, and longest in the intermediate-size forest properties. Seeding with Scots pine (Pinus sylvestris L.) was used in almost all regeneration areas.

The forest owners had mainly carried out the regeneration work themselves. In the Pohjois-Häme area, the interval was shorter when the district forestry board regenerated the area. 35% of the regenerated areas had required supplementary planting in Pohjois-Häme, and 47% in the Uusimaa-Häme area. Supplementary planting was more common in areas regenerated later after the cutting. In Pohjois-Häme, according to the reports of the forest owners, 75% of the regenerated areas required tending during the first three years, in Uusimaa-Häme, 80%.

The PDF includes a summary in English.

• Yli-Vakkuri, E-mail: py@mm.unknown
• Autio, E-mail: aa@mm.unknown
• Vehkaoja, E-mail: jv@mm.unknown

The present paper presents studies on the influence of some relatively common defects of Scots pine logs in Northern Finland on both the sawing yield and on the quality of the sawn goods. The study was based on test sawing of 25 logs for each of the defects (upright limb, heart shake and various kinds of wounds and scars) at Karihaara sawmill. The yield was graded into grades used for export timber according to the system of the sawmill. The proportion of the different export grades (U/S), fifths, sixths and culls) were used as characteristics together with the ratio of raw-wood consumption expressed as cu.ft/std.

Upright limbs occurring in a piece of sawn timber was shown to lower its quality to fifth grade in 43.5%, to sixth grade in 46.8% and to the category of culls in 6.5% of all cases. Only 3.2% of the cases the piece remained in U/S-grades. The size of the upright limb was the most important factor lowering the quality and affecting the ratio of raw-wood consumption.

Heart shakes are relatively common defects in pine logs deriving from over-mature trees. The quality-decreasing influence on the sawing yield depends clearly on the length of the shake in the cross-section. The same characteristics also decreases the ratio of raw-wood consumption. In addition, twisting and star shakes are considerably more harmful than straight ones. If rot occurs in connection with shakes, the places marred by the shakes are only capable of yielding sixth-grade sawn goods or culls.

Scar encountered in logs affect the sawn yield and its quality to quite a varying degree, but these defects themselves may also vary considerably both in size and quality. The length of the scar is highly significant as a quality-decreasing factor. If, in addition, rot is encountered, the defect is of a severe nature.

The PDF includes a summary in English.

• Heiskanen, E-mail: vh@mm.unknown

This article is a book review of a book Établissement des courbes de variation de la densité du bois par exploration densitométrique de radiographies d’échantillons prélevés à la tariére sur des arbes vivants’ by Hubert Polge.

• Hakkila, E-mail: ph@mm.unknown

The paper outlines the information about forest tree nurseries in the Roman Empire, found in ancient writings. According to the author, it cannot be stated that actual forest cultivation was practiced in the times of the Roman Empire, even if tree seedlings were used for a variety of purposes, such as embellishment of cities, parks and gardens, and raising supporting trees in forest vineyards. Nurseries were usually established on farms to fill the owner’s needs. For instance, Gato, Varro, Virgil, Pliny and Colulmella have given instructions about establishment and management of nurseries, and methods to sowing seeds of different tree species. Except for seeds, both root- and branch-cuttings were used in cultivation of trees. Also, grafting was known.

The PDF includes a summary in English.

• Makkonen, E-mail: om@mm.unknown

The present study is an examination of the problems involved in raw-wood inventory from the viewpoint of business economics. The term inventory used here includes the standing timber marked for cutting as well as delivery contracts. The task of inventory is to buffer the differences in timing, locality, quantity and quality caused by purchase, production and delivery processes. The basic problem is concerned with profits.

The basic aim is to keep the inventory small. Its limits are determined by comparing the storage costs and costs of shortage. The costs may be decreased without risking the reliability of deliveries by technical development and road improvement, which also decrease dependence on the seasonal variation of harvesting of timber. A model based on present practices, statistics and practical experiences can be used to calculate different alternatives. The volume of purchases, felling, deliveries, transportation, and differences in quantities and transfer is used to estimate the target level of the inventory. It forms a forecast which the future performances can be compared to. In addition to monitoring turnover rate of the total inventory and capital tied to the inventory, also the exceptions in structure, time and quantity of the inventory and the factors changing it should be monitored. A special difficulty in timber inventory book-keeping are the continuous variations in the measured volumes even if no loss occurs.

The PDF includes a summary in English.

• Einola, E-mail: je@mm.unknown

Due to mechanization of draining of peatlands, also open peatlands have been included in the draining projects due to technical reasons. Some research has been published on afforestation of open drained peatlands, but there is yet no experiments that reaches the entire development of the stands. The purpose of this paper is to discuss the possibility of extending the planting season of Scots pine (Pinus sylvestris L.) over the entire growing season in drained peatlands, where the water condition of the site is probably not the factor limiting forest development. An open low-sedge swamps in Southern Finland were planted in early summer and two weeks in midsummer in 1967.

In the light of the results, planting Scots pine would seem possible in drained peatlands throughout the growing season. However, plants may suffer considerably from lifting for the plantation in August. The success of planting at the turn of September and October is also uncertain. The nursery must be situated close to the areas to be planted, since the transportation and handling of plants during the growing season must be carried out with extreme care. The seasonality of planting work could be decreased by extending the planting season. In the future, several transplant storing methods should be tried out in connection with similar planting-time experiments.

The PDF includes a summary in English.

• Päivänen, E-mail: jp@mm.unknown

The paper lists the papers of forest scientific research published in Finland in 1967 by the scientific series Acta Forestalia Fennica, Silva Fennica, Communicationes Instituti Forestalis Fenniae, Folia Forestales, and Metsäteho Reports.

• Finnish Society of Forest Science, E-mail: –

The aim of this paper was to shape and analyse certain alternatives in the development processes in the organization chains of Finnish forestry. The material was collected by analysing market structures and characteristics of competition with regard to raw wood and forest industry products.

The paper presents two alternative ways to rationalize the organization chains between the forest owner’s organizations and forest industry. In the price mechanism of raw wood originating from Finnish private forests there there has been increasing influence of the central organizations of the private forest owners and forest industry. In their relationship, the model of bilateral monopolistic competition can be chosen as a conceptual framework.

Under bilateral monopoly price is fixed as a result of negotiations between competitive parties, and the position and tactics within the negotiations are of great importance for the negotiating parties. Because of the competition, Finnish forest industry cannot compensate the increase in the production costs by raising independently the export prices of its products. This and the fact that the annual earnings of forest workers are fixed by law to the earnings of the workers in wood-processing industry, will cause pressure on stumpage prices.

In the paper two schemes are outlined. In the Scheme 1 a development alternative is described in which the organization chain of private forest owners is supposed to develop to the industry growing direction. In the Scheme 2 the organization chain of private forest owners is supposed to develop to the organizational orientated direction.

It is concluded that as long as the forest owners’ organizational orientated central organization is too weak to form a monopoly as counterweight to the monopsol of forest industry (except the industries of forest owners), it will consider the industry growing direction superior to the organizational orientated alternative.

The PDF includes a summary in English.

• Rinkinen, E-mail: ir@mm.unknown

The present study gives an account of the dependence prevailing between the actual volume of timber crops, and, on one hand, the sum of cylindrical volume of individual trees, and on the other hand, the utilization per cent. This dependence is rectlinear if the volumes in question are calculated on a running-foot basis. The cylindrical volume of individual trees was calculated on the basis of cross-section area at breast height and the height of the trees. On the basis of the results, it seems that it is possible to simplify timber measurement.

The PDF includes a summary in English.

• Nisula, E-mail: pn@mm.unknown

The aim of the present study was to find the factors influencing the distribution of Norway spruce (Picea abies (L.) H. Karst.) logs on various grades with special stress on the effects of the grade on the value of logs. The material was obtained from ten sawmills located in Southern Finland by grading a total of 13,559 logs.

The results showed that knottiness in its different forms of appearance is the most important factor influencing the quality of spruce logs. Its significance is clearly greater in spruce than in Scots pine saw logs. Among the other defects, the most common are crooks. Even scars and decay occur to a considerable degree, but other defects seldom affect the grade. The quality of butt logs is markedly better than that of top logs. Both in butt and top logs the smallest logs in diameter are of poorer quality. However, in the largest diameter classes the quality begins again to decrease.

The difference in the quality of logs of the same grade at various sawmills is very small. The results of grading at varying times at the same sawmill show greater differences than can be observed between different sawmills. However, the logs of sawmills that procure the timber from coastal areas and islands are inferior to those which procure the timber from the mainland.

The PDF includes a summary in English.

• Heiskanen, E-mail: vh@mm.unknown