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EN
The aim of this work was to analyze the tree−ring width, the share of the latewood as well as the density of wood of trees growing in commercial and degraded stands. The research was carried out in the Brynek Forest District (southern Poland) in 3 commercial stands and in 4 degraded stands. For every study plot fifteen spruces were chosen and increment cores were sampled using the Pressler borer. Next, the surface of the cores was smoothed and the width of the annual rings was measured. Latewood zones were determined and the share of latewood was calculated. It was found that the average and minimum tree−ring width was the same in both commercial and degraded stands, while the maximum values were slightly and insignificantly different. In turn, the average share of latewood was higher in trees from commercial stands, but higher minimum and maximum values were recorded in stands on degraded sites. In this case, the differences turned to be statistically significant. The average density of wood was slightly lower in trees from degraded stands compared to wood from commercial stands (413 vs 418 kg/m³). The minimum and maximum values were also higher in trees from commercial stands. However, this feature did not show a significant difference between analysed groups of stands. We found that despite such significant differences in the terrain formed during the production of zinc and lead ores, the wood of trees growing in these areas hardly shows any differences (except for the share of latewood) in comparison to wood from commercial stands.
EN
The paper compares the properties of Norway spruce (Picea abies (L.) Karst.) wood from stands growing in the lower and upper subalpine forest zone in terms of the tree−ring width, the share of latewood and the wood density. The investigation concerned material originating from plots established within the boundaries of the south−western incidence of spruce in Poland. Plots were located in the Sudety Mts. and in the Carpathians (tab. 1). On each plot fifteen Norway spruces were chosen and increment cores were sampled using the Pressler borer. The surface of the cores was smoothed and the tree−ring width was measured. The latewood zones were determined and the share of latewood was calculated. Then, the cores were divided into 2 cm sections, for which the relative wood density was determined. Tree−rings were wider in trees growing in the lower when compared with those from the upper subalpine forest zone (tab. 2). Weak negative correlation was revealed between the elevation and the tree−ring width (r=–0.308). The latewood share was slightly higher in trees from the upper than those from the lower subalpine forest zone (tab. 2). However, no statistically significant correlation between the latewood share and elevation was recorded. The wood density was slightly lower in trees from the lower than those from the upper subalpine forest zone (tab. 2), but the difference was not statistically significant. The correlation between the wood density and the elevation turned out to be insignificant.
EN
The paper contains analyses of pine wood features, carried out on 27 areas, representing forest stands on Carpathians and Sudetes area. On studied area it was possible to separate origin groups differing according annual growth widths, late wood contribution and its density. The highest values these features entertain in wood of pines on areas of Bieszczads, whether the lowest ones in origins recognized as montanes. In Beskidian forest stands, values of wood features were intermediate.
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