Current issue: 58(5)
Silva Fennica no. 115 | 1963
Category : Article
No other manifestation of life is allied more conspicuously to the theory of relativity as the growth of forest stands which is a function of the inherent growth potential of trees, the productive capacity of environment, and time.
The height over age quotient of a forest stand is usually the most reliable indicator of the productive forces of the habitat. Stem analysis have shown that increment of a tree at different ages is closely correlated with the extension of roots into individual geological horizons of different productive capacity. Growth curves of stands of a same tree species growing on different soils can be disparate due to different conditions. The temporal variety of tree growth on different sites is of prime importance in the construction of yield tables. Investigations of natural plant communities of Finland provided one rational approach towards the construction of yield tables. By confining mensuration analyses to define floristic types, the Finnish foresters harmonized their records with Einstein’s formula for space-time matrix of material events.
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Wilde,
E-mail:
sw@mm.unknown
On the basis of time studies on pruning, one thousand stems in four stands was pruned, carried out in 1962. The work was done in two phases with Olli pruning saw, first attached to a shaft about 1.8 metres long and the to a shaft about 4 metres long.
The total time of moving from one stem to another when pruning the stem varied from 0,28 to 0.31 min per stem in the different working sites. The resting time was 19–20% of the effective working time, which included actual pruning time and the moving time. In average, 7.5% of the actual pruning time was unproductive. The actual pruning took in average 0.75–1.1 min/stem in the different sites. The time depended on size of the tree, the DBH, and on the length of the part to be pruned. The total working site time for the pruning was in average 1.34–1.98 min/stem. The output of the work per 7 hours’ working day varied from 226 to 280 stems, and the costs from 10 to 14 pennies per stem.
The PDF includes a summary in English.
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Heiskanen,
E-mail:
vh@mm.unknown
This paper describes different methods of long-term forecasts in forest management planning with a special attention on intention forecasts for a total forest property or district. Methods for calculating the sustained yield on the basis of the actual increment or the yearly area cut are discussed. It is concluded that a better estimate of the sustained yield is obtainable by the application of a long-term forecast technique. Forecasts for 100 years should not be viewed as plans, but as a background for making short-term decisions. Some of the long-term-type programmes, such as the programme of maximum profit, sustained yield in volume and in money are discussed briefly.
It is pointed out that there is often present a conflict between the various elements of the policy formulated by a forest owner. This leads to the conclusion that the calculations of the profitability of single projects may be misleading.
The precision of a long-term forecast is discussed, and how under certain assumptions the error of the allowable cut is influenced by errors in area, volume, age etc. It is shown that the precision in area and volume is more important in this connection than, say, the precision in increment. In conclusion, existing knowledge, methods and equipment for calculations constitute a basis for long-term forecasts which make them an important instrument in forest management planning.
The PDF includes a summary in English.
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Seip,
E-mail:
hs@mm.unknown
The purpose of this investigation was to construct a procedure for measuring the profitability of the use of waste wood. The average price a sawmill gets from the waste wood depends, on the amount of use compared with the waste wood output, and on the composition of waste wood. Production of different kinds of waste wood presupposes investments, therefore, the size of a sawmill, in addition to its location, affects the composition. The data was collected by mailing a questionnaire through the central organizations of the sawmill industry in 1959.
The amount of waste wood per standard of sawn wood increases with the size of the sawmill. Because small sawmills cannot generally use or sell their waste wood, they strive at using the raw material effectively. In addition, they produce much rough-edged sawn wood, and sorting is not as strict as at large sawmills. They also leave their sawn wood untrimmed.
Finland’s pulp industry has expanded significantly since 1958. This has increased the need of raw wood, and the demand of sawmill waste. An additional data collected showed that in 1958 there was about 150 and in 1963 about 200 sawmills delivering waste wood to the forest industry. The amount of waste wood used as raw material compared with the total waste wood utilization had increased about 10% during the period. The production of cellulose chips became profitable when the annual output of sawn wood of a sawmill exceeded 1,000-2,000 stds. The size structure of the sawmills affects the regional usage of the waste wood.
The PDF includes a summary in English.
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Rinkinen,
E-mail:
ir@mm.unknown
The present article reviews a geological report given by Daniel Tilas, a Swedish mining manufacturer, towards the end of the 1730s as the report regards information on the Finnish forests. His report gives at hand that forests in several localities southwest of the region demarcated by the towns of Loviisa, Äänekoskei and Kristiina were seriously diminished or burdened by tar burning and shifting cultivation. Larger saw log stands were found mainly in the scaterly populated parishes of Central Finland. Thus, in the chain of ridges between Orivesi and Ruovesi, covering an area of about 4,000 km2, there was a heavily stocked Scots pine forest, as reported by Tilas.
The report given by Tilas is kept in the files of the Geological Research Institute in Helsinki.
The PDF includes a summary in English.
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Laitakari,
E-mail:
al@mm.unknown
One forest drainage undertaking in Finland often consists of woodlots belonging to several owners, and over hundred owners may be involved. In the present paper a method for allocation the costs to different owners in a joint drainage undertaking is worked out. The problem has been emphasised by the new Waterways Law, which enables also such drainage projects to be undertaken to which some of the land owners oppose. In those cased the costs must be allocated according to the benefit driven by each owner from the project.
The method attempts to assess the benefits to be driven from the forest drainage, those costs of the drainage that are joint and thus subjected to allocation, and what is the area affected by drainage as used as a basis for cost allocation.
The joined costs are apportioned in the following manner. The area of peatland adjusted to differences in the benefit obtained by drainage is ascertained by the land holder by multiplying the index number by the corresponding areas. In the case of cultivated agricultural land, also an index showing the need for drainage is used in computing the adjusted area. Each topographic unit in the map is provided with a notation of its apportionment area. Joined costs are allocated to different land owners in relation to their adjusted land areas.
The PDF includes a summary in English.
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Heikurainen,
E-mail:
lh@mm.unknown
- Keltikangas, E-mail: mk@mm.unknown
- Seppälä, E-mail: ks@mm.unknown
