The decrease of Silver Fir in fir-beech forests in addition to climatic factors and methods of forest management is also affected by large herbivorous ungulates, which may hinder the regeneration of forests by browsing young trees. The purpose of thesis was to investigate the effects of size of gaps on browsing level on Silver Fir and other tree species caused by herbivorous ungulates. Inventory of regeneration was conducted in summer 2008 on 120 plots (1,5m x 1,5m in size) in GGE Črni Vrh. Half of plots were chosen on small canopy gaps or near small gaps, other half on large gaps or near. Large gaps were defined as gaps with diameter of more than two tree height, while small gaps as gaps with diameter of 0,5-1 tree height. Specifications and measurements were conducted using GPS device. Total damage on saplings inside gaps was 69%. Damage on Silver Fir was high % 81%. Consequently, fir rejuvenation as an important builder of fir-beech forests is very difficult, in some areas even impossible. High browsing pressure was found also on other tree species. Damage on Sycamore Maple, which was the most frequent tree species in saplings, was 78%. We did not find differences between the densities of saplings in small and large gaps; moreover, we did not find statistically significant differences in the level of browsing between small and large gaps. Results show that after felling we do not minimize browsing with forming larger gaps but probably do not improve nutrition supply for herbivorous ungulates. The silviculture should be largely devoted to a balanced state of development phases, rather than adjusting the size of the gap. This will improve the conditions that will allow the game a sufficient amount of quality food and the woods the smooth process of rejuvenation of all tree species.
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