European larch presents one of the key tree species of high-altitude forests in the Alps. We studied the structure of larch forests, the growth of larch and the differences in the quality structure of larch along an altitudinal gradient of 1500-1800 m on the Dleskovška planota in the Kamnik-Savinja Alps. We set up 20 research plots of 20 x 20 m in size. We carried out a full callipering of stands, inventoried regeneration, surveyed visible external defects of the trunk, and took two cores from two randomly selected larch trees in each plot. In relation to elevation and stand mixture, local chronologies were calculated and larch diameter growth was represented by growth functions. In addition, the impact of climate change on diameter growth of larch trees was evaluated. The assortment structure of timber was determined according to the Rules on Measurement and Classification of Forest Wood Assortments (2017). Along the increasing elevation gradient, there was a decrease in the values of most stand parameters and an increase in stand heterogeneity. Larch was growing the fastest in diameter at the lowest-lying plots, where we also found a very early culmination of diameter increments. Radial growth of larch was found to be greater in mixed than in pure stands. The expected impact of climate change was observed only with the larch local chronology at 1800 m, where a constant increase in the tree ring width was detected over the last century. In the assortment structure, there was a predominance of the C-grade assortment class (16.2%) and a statistically significant decrease of proportions of all assortment classes with elevation was determined. We conclude that elevation influences the structure of larch stands, diameter increment decreases with increasing elevation, and climate change seems to have the expected impact on increasing diameter increments only at the highest altitudes of larch occurrence.
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