The relationship between bark damage to Chamaecyparis obtusa by the Asiatic black bear, Ursus thibetanus, and resulting trunk rot and staining: a case study of a 62-year C. obtusa stand in Shizuoka prefectural forest.

摘要

Elongation of the area of stem rot and staining of Chamaecyparis obtusa, from which bark had been peeled by the Asiatic black bear, Ursus thibetanus, were examined in a 62-yr-old stand at Iwasaki in Shizuoka prefectural forest, Japan, in April 1994.Ten damaged trees, which had already been felled for thinning in February 1994, were randomly sampled; measured mean tree heights and base diameters were 15.4 m and 37.3 cm, respectively. The mean ratios of rot height (mean=1.82 m) and stain length (mean=3.35 m) to the heights of peeled bark (mean=1.39 m) were 1.32 and 2.56, respectively. There was a significant positive correlation between the height of the peeled bark and rot height, but no significant correlation between the height of peeled bark and the stain length. This indicates that more severe damage by bears increases the length of stem rot.