Abstract
The choice of particular trees for stripping by deer is puzzling because a preference is observed for trees of the highest social class. Trees ranked highest in the stand can produce more carbohydrates as a product of carbon assimilation. Among the many important nutrient and defense groups of metabolites in plants, high sugar content is postulated to be an attractant due to its impact on the sense of taste of different herbivores. Thus, we hypothesize that the carbohydrate content in the bast of the European beech is the most important factor by which deer make their choice. Our aim was to assess whether the sugar content in the bark and in the bast can be a factor which influences the intensity of bark stripping of particular trees in a beech thicket by red deer. A single episode connected with tree damaging pertained to 7% of the trees on the analyzed sampling plots. In total, 27% of the trees were damaged, including old damages. The mean size of damage to a given tree equaled 36% of the tree's circumference and 0.06 m(2) of the trunk's surface. Analysis of the sugar content in the bast and in the bark jointly indicates that the trees subjected to bark stripping possessed a distinctly higher sugar content than the trees which were not damaged. The probability of bark stripping grows together with an increase in the sugar content of the bark and of the bast.