Tree growth space of larch (Larix decidua Mill.)in relation to age, forest habitat type and biosocial position

Abstract

The study presents the results of an analysis of the variance of the characteristics of single tree growth space. The study involved larch trees of Kraft’s class I, II and III (dominant stand) in stands of different age classes growing on optimal and rich forest sites. The following measurements of the single tree growth space were selected and determined: crown projection area – pk (m2), crown diameter – dk (m), Seebach’s growth space number – dk/d1,3, and crown deflection coefficient – dk/h. The research material consisted of the measurement of 48 larch trees, from 16 stands growing on optimal and rich sites. Sample trees were selected from four successive age classes starting with class II in accordance with the assumptions of Hartig’s method. Three sample trees with properly developed crowns were selected from each stand. The crown projection area was calculated as the area of a circle with a radius equal to the average radius of the crown (the average crown radius was established after crown projection in the four main geographical directions). The real height was determined after the felling of trees. Basic statistical characteristics were established. A three−way variance analysis was performed assessing the statistical significance of the impact of the forest site, age and biosocial position of the trees in a stand. Basic statistical characteristics were established. The three−way variance analysis was performed assessing the statistical significance of the impact of the forest site, age and biosocial position of the trees in a stand. The performed analysis showed a statistically significant effect of stand age on Seebach’s growth space number and crown deflection coefficient. In the research, the biosocial position of larch in a stand affected the size of the crown projection area and the crown diameter, and the relationship was statistically proven.