Abstract
Serious damage caused by glaze occurred in the forest of Hidaka from the 22nd to the 23rd of February 2004. The entire damage area has reached about 163 ha where 84% of the area is occupied by Japanese larch (Larix leptolepis Gordon) forest. In this research, the weather conditions at the time damage occurred were investigated, and the relationship between the damage rate to Japanese larch forest and site conditions was analyzed by using various analysis methods. It was considered that a warmer air (air temperature above 0°C) layer must have existed at the upper air (more than 400 m in altitude) during the nights of 22nd and the 23rd. This is why the glaze did not damage the higher altitude area. The scores of aspects were higher in the N-NW direction, which suggests that the damage might have been expanded by the winds after ice accretion. The scores of the average diameter at breast height indicated that the damage rate in larger diameter (>25 cm) threes was reduced.
