Current issue: 58(5)
Articles containing the keyword 'storm damage'
Category : Article
A big storm hit Finland in 12.10.1933, and caused forest damages especially in the coasts of the Gulf of Finland and Baltic Sea, and in the eastern part of the country. In these areas the wind felled about 75,000‒85,000 m3 timber trees in the state lands. The extent of the wind damage was measured in forest area of 1,500 hectares in Lapinjärvi in Southern Finland. The wind had felled 42% of the Scots pine (Pinus sylvestris L.), 70% of the Norway spruce (Picea abies (L.) H. Karst.) and 44% of the Betula sp. trees. Thus, Norway spruce had been most susceptible for wind damage. That extensive damages in Norway spruce seed tree stands risk the regeneration in the area. Natural regeneration of Norway spruce using seed trees may, therefore, be questioned. The seed tree areas on hills, and especially hollows next to the hills were susceptible for wind damage. A denser border stand protects sparsely stocked seed tree area. The damages were also smaller in older seed tree areas, where the trees and ground vegetation had had time to recover after the felling. The felled spruce and birch trees had often stem rot.
The PDF includes a summary in German.
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Cajander,
E-mail:
ec@mm.unknown
The article represents, based on meteorological data from 1900-1910 and 1911-1915 and annual reports of forest directorate with descriptions or statistics about wind damages of trees in state owned lands, the biggest storms in Finland and the damage they have caused to forests. The most powerful storms of the studied period and damages they caused are presented.
It was found out that the storm damages take place primarily during the growing season. Frozen ground and a snow cover protects the trees from falling.-
Bonsdorff,
E-mail:
ab@mm.unknown
There are lot of storm damages in the Finnish forests. They are particularly common in forests logged as strips or with clear cuts, but not absent in selection forestry either. To protect the forests from natural disasters requires more intensive management. For the forestry purposes it is important to know the most common wind directions of different parts of the country. The paper finds out which stormy wind directions are most dangerous to Finnish forests and hence need to be mostly taken into consideration when planning logging operations. The study is based on meteorological data that has been compared with the reports of storm damages in state owned forests.
The most storm damage take place during the growing season, and to some extent in late fall. The regeneration felling should take place against the primary direction of the stormy winds. The paper represents the most common wind directions for different parts of the country. However, the wind directions may vary from the primary with local conditions such as altitude differences.
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Bonsdorff,
E-mail:
ab@mm.unknown
