Current issue: 54(4)
Under compilation: 54(5)
The material used in this study was collected in 1975 from a 41-years old curly birch (Betula pendula f. carelica Sok.) stand in Southern Finland, which had been pruned 12 years earlier. While the stand was thinned, 26 felled trees were selected for further study to study occurrence of discoloration originating from of pruned branches.
The study material included 35 pruned branch stumps and 38 naturally pruned branch stumps of curly birch. The mean diameter of the former was 31 mm and of the latter, only 15 mm. Of the pruned branch stumps, 23% had become completely sealed-off within 12 years. The discoloration had spread into the stem as little from pruned branch stumps as from naturally pruned ones even though the former were greater in diameter. Advanced rot was not found in any of the samples studied.
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