Abstract
The avalanche hazard area (Fig. 1) in the mountain of Teshio Experiment Forest of Hokkaido Univ., in the northern part of Hokkaido, was researched through winter and summer of 1966 to get information of vegetation's damaged forms on snow sliding zones. In this area, many ground avalanches occured on slopes with a southern aspect where Sasa Macrochlamys grew thick and few broad-leaved trees were scattered after two forest fires of 1926 and -27. They broke out on feet of slopes with a northern aspect, too. The features of the vegetation on avalanched slopes are as follows: 1. Stands are small and bushy (Table 4). 2. Trunks slope near level to valley side and no branches are observed at hill sides of trunks (Fig. 3). 3. The hill side barks of Betula Ermani are stripped over. 4. As compared with an non-avalanched slope, Sasa Macrochlamys grow much the same in density, but smaller in height and diameter (Table 5).
