Acta Forestalia Fennica vol. 53 | 1946

This investigation concerns the felling volumes in Finland in 1935-1945 as regards future fellings. The statistics are divided in two time periods: 1935-1939, when there was an upward trend in the trade cycle, and 1940-1945, when the trade was disturbed by the Second World War. Fellings of household timber and for sales are presented separately.

Removal was annually in average 38.1 million cubic meters (cbm) without bark in 1935-1939, and 29.8 million cbm in 1940-1945. According to the statistics, felling volumes decreased by about one quarter after the period of 1935-1945. Reduction was largest in private and company forests, but smaller in the state forests. The increment balance for the 1935-1945 shows an excess of growth that gives an accumulated yield of 24.4 million cbm.

In private forests the cut is about half as large as the growth of the standing stock due to the poor silvicultural condition of the forests. Private forests account for about ¾ of the total forest area in Finland. In the state lands the cut is 130% of the growth. The report introduces also rental cut, a method developed by the writer, which defines the volume to be cut aiming at the same time to optimise the future increase of the yield. The principle is to preserve the young and vigorous stands, while cutting stands that have low growth.

According to the statistics, the felling volume of private forests has followed the variations in demand. It seems likely that in the coming years the fellings will not be kept within the limits calculated by the rental cut. Consequently, the reserve formed during the war will be utilized. To meet the demand of wood, forest management must be improved and preference should be given to regeneration fellings. Improving transportation systems, such as roads, would give access to forest resources that are now difficult to harvest.

The PDF includes a summary in English.

• Lihtonen, E-mail: vl@mm.unknown

The aim of the study was to collect the first complete statistics on pastures and grazing of cattle in Finland. The data was collected in connection with an investigation of wood utilization in 1937-1938. Overall trend in grazing is that forest pastures are being replaced with restricted forest pastures and those further with hay meadows. This development is proceeding in the whole country, and it is almost completed in Western Finland. Grazing will probably be transferred completely to cultivated lands in the coming decades. This is important question also for the forestry, because of the damage grazing causes for forest.

Forest pastures are, however, still very important in animal husbandry. They produce over 500 million forage units. It would require 400,000 ha of hay meadows to produce corresponding amount of fodder. To sustain the present number of cattle, a third of all arable land in Finland should be hay meadows. The main goal for development of pastural agriculture is improving the effectivity of grazing and productivity of the pastures.

The PDF includes a summary in German.

• Jäntti, E-mail: aj@mm.unknown

According to the theory of peatland types, particular peatland types, after sufficient drainage, change into certain forest types. It has been found, that the range of forest types in peatlands in different stages of draining is as large as on mineral soil; and comprise Cladina, Calluna, Vaccinium, Myrtillus Oxalis-myrtillus and grove types. Poor peatland types change into poor forest types, better for better types. However, a Swedish scientist Mellin suggested that after effective drainage especially oligotrophic bogs, when well drained, change usually into Myrtillus type.

The different conclusions are due to the fact that the same bog type may develop into different forest types according to the effectiveness and duration of the drainage. Greater the decay of the peat bog layer, the more exacting is the type of vegetation which appears. Bog types of classes V, IV and III (Finnish classification of site quality) change into a Myrtillus type, as do the poorer peatland types of class II. The types vary, however, in their economical drainage value. The fact that bogs which in their natural stage are clearly different in their site quality change after through drainage into the same forest type, is explained by the chemical quality of the peat. However, class I and the best types of class II bogs change into better forest types because they as eutropchic bogs are richer in nitrogen and lime. This difference persists despite of effective draining.

It has been shown that the development of eutrophic peatland types at the forest type stage also differs clearly from the development of oligotrophic peatland types. The Finnish classification of drainage value shows correctly the relative drainability when using normal spacing of ditches. The notes on forest types on mineral soil should, however, be replaced by corresponding notes on the transitive types between bog and forest types.

The PDF includes a summary in Swedish and English.

• Keltikangas, E-mail: vk@mm.unknown