Tending and thinning of younger forest stands is the main cost for the owner in managing the forest. In order to reduce costs, alternative methods of thinning (i.e. situational thinning) have been developed in addition to the classical selective thinning. In order to monitor long-term effects of different types of thinning, a research facility was established in the Forest management unit Mirna gora. In pure beech stands eight 4-9 are large research plots were established. The types of thinning analyzed were classical selective thinning (treatment A), situational thinning after Abetz (treatment B), situational thinning after Schütz (treatment C), and control (treatment D). The thinning types were randomly assigned to the plots. All trees above the threshold of 5 cm were registered on each plot. The thinning intensity with respect to the number of trees, the basal area, and the growing stock was higher at treatment A than in treatments B and C. The thinning intensity, expressed as the number of competitors per crop tree, was lower in treatment A than in treatment B and higher than in treatment C. The proportion of sycamore maple among the crop trees was higher than its share in the total number of trees. Our study suggested a preference for situational thinnings over conventional selective thinning, but more reliable findings will be provided after re-measurements and re-evaluation of gathered data.
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