DIGITALNA ARHIVA ŠUMARSKOG LISTA
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| ŠUMARSKI LIST 5-6/2015 str. 44 <-- 44 --> PDF |
stand (0.32 wounds per winching operation) and 27 trees in the pure stand (0.24 wounds per winching operation). Next in importance was damage to the stem. The total of partially or fully uprooted trees was 17 in the mixed stand (0.11 trees per winching operation) and 16 in the pure stand (0.14 trees per winching operation). Damage to the butt end and crown was not recorded, whereas damage to the regeneration was very pronounced. In the mixed stand, damage to 116 young plants was recorded, i.e. 0.78 damaged plants per winching operation. In the pure stand, the number of damaged plants was 36, i.e. 0.32 plants per winching operation. In order to determine the percentage of damaged trees along the skid trail, the number of trees in the zone of possible damage was first specified. The length of skid trail in the mixed stand was 900 m and 963 trees were located in the area of increased risk of damage. In the pure stand the length of skid trail was 600 m, and the number of trees counted on both sides of the skid trail was 276. During the timber skidding to a roadside landing on a truck road, the most common type of damage was to the butt end. The total number of wounds to the butt end in the mixed stand was 116. In other words, 12% of trees located along the skid trail were damaged in this way. In the pure stand, a total of 51 wounds to the bole were recorded, and 18% of trees along the skid trail were damaged. Damage to the root collar of the trees located along the skid trail was observed in 30 trees in the mixed stand and 9 trees in the pure stand (in both cases about 3% of the total number of trees). The recorded number of injuries to the stem was 14 (1.45 % of the total number of trees) in the mixed stand, whereas uprooting of 5 trees (1.81 % of the total number of trees) was observed in the pure stand. In the zone of potential risk of damage along the skid trail, the number of plants counted in the regeneration storey was 669 in the mixed stand and 161 in the pure stand. During the timber skidding, 166 plants (0.78 plants per winching operation) were damaged in the mixed stand, whereas the number of damaged plants in the pure stand was 34 (0.31 plants per winching operation). Most of the wounds occurring during the timber extraction have areas ranging from 50 to 200 cm2. The minimum wound area is 12 cm2, whereas the maximum wound area reaches 600 cm2. The average wound area is 145.4 cm2 in the mixed stand and 176.6 cm2 in the pure stand. DISCUSSION RASPRAVA Trunk parts of coniferous tree species are on average by 18.67% longer than the trunk parts produced from beech trees. Consequently, the number of assortments produced per tree is smaller, which had an impact on the number of pieces in the optimal load. The results of this survey indicate that there are significant differences in the type and number of incurred injuries between the phases of felling and timber extraction, both |