Vliv buřeně na odrůstání kultur douglasky tisolisté

The aim of the study was to determine the influence of weed growing up on Douglas fir cultures using different methods of protection against weeds. There were used several methods as: whole surface trimming, trimming in stripes, individual trimming, trampling, whole surface herbicide application, trimimming the grass blades to a height level. As a control area was chosen an area with no treatment against the forest weeds. The research was carried out on forest property LHC Horáková, set of forest types 5H. In the spring of 2012 was established a research area, which was divided into seven parts, each part for a different kind of protection against forest weeds. On each plot were planted approximately 200 individuals of Douglas fir. For seedlings were evaluated the following criteria: length of the aboveground parts, terminal increment, replacing of the terminal shoot by lateral shoot, thickness of the root collar, the occurrence of tress with fork trunk shape, multiple top, trunk straightness, canopy shape, color of needles, length of needles, crown base height and damage of tree by biotic and abiotic factors and total losses. There was also examined the effect of treatment against weeds on soil moisture, sunlit of seedlings on individual plots, the species composition of weed on individual plots and the influence of different intervention against weeds on the chemical composition of the assimilation apparatus. It was found out that Douglas fir exibits the greatest terminal increment on area without treatment, and after three years of research achieving an average height of 121.7 cm. But seedlings on this plot have weaker root collar (15.61 mm) and also have relatively high slenderness ratio. The strongest root collars are at the end of the research identified on a plot with individual trimming - 19.71 mm, at the same time the seedlings have comparable terminal increment to that area without any treatment (119.7 cm). The least suitable way to protect against forest weeds after three years of research, was found out herbicides treatment, because it showed the worst results. The best way in contrary seems individual trimming