An appropriate management of pedunculate oak (Quercus robur) stands requires well-planned rejuvenation, followed by regular and appropriate silvicultural measures, including thinning of younger and middle-aged stands. These measures represent the highest costs of forest management. To reduce them new concepts of thinnings has been developing (i.e. situational thinnings), the effects of which need to be tested in forestry practice. Thus, the main objective of our research was to establish a permanent research site in pedunculate oak forest that would enable comparison of selective and situational thinning concepts and will serve for monitoring the effects of both thinning concepts in the long term. The Senuša research site was established in young oak stands in the Krakovo forest management unit. The research site consists of 6 research plots of 900 m2 and 2 research plots of 625 m2. We applied and analysed selective thinning (treatment A), situational thinning with the final crop trees (treatment B), and stands under natural development (control, treatment C); the treatment was determined to the plots randomly. At the time of establishment, the average number of trees per plot was 10,750/ha, of which 67 % were pedunculate oaks. In treatment A, 622 crop trees/ha were selected, while in treatment B only 81 crop trees/ha were selected. The thinning intensity in relation to the number of trees was higher in treatment A than in treatment B (19.3 % and 4.8%, respectively), while the thinning intensity in relation to the number of competitors per crop tree was higher in treatment B (6.2 and 3.1 competitors/crop tree, respectively). Our results do not allow firm conclusions on the suitability of the two thinning concepts in pedunculate oak stands. For that, at least the first consecutive measurement after few years will have to be waited.
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