Wind and snow damage in a thinning and fertilisation experiment in Pinus sylvestris
1994
Valinger, E. | Lundqvist, L. | Brandel, G.
Damage induced by wind and snow was examined in an experimental series with thinning and fertilisation established in 34-58 years old Scots pine (Pinus sylvestris L.) stands in northern Sweden during the period 1969-83. The experiment contained six treatments and 23 replications. The treatments were 25% and 60% thinning from below, 25 % thinning from above, 30% thinning from below combined with N and NP fertilisation. Percentages represent basal area harvested at the first thinning. Differences in damage level were examined at the first reinventory, 4-8 years after thinning. The level of wind and snow-induced damage was about 1% of the basal area during the period studied. Proportion of basal area damaged was not affected by the treatments, but there was more snow damage after thinning from above than after thinning from below. The proportion of trees damaged by snow and the proportion of dead trees were affected by treatment. The densest stands, the control and 25% thinning from above, were damaged the most, and had a greater proportion of dead trees. Although not statistically significant, plots subjected to the fertilisation + thinning treatment had a greater proportion of dead trees than plots that were only thinned. Significant differences between blocks were found for proportion of both basal area and number of trees damaged, which could be explained by differences in, e.g., altitude and latitude.
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