Stand Density of Avalanche Prevention Forest

Abstract

The relation between the stand density or the intervals of broad-leaved trees over 5 cm in diameter, and the stability of accumulated snow in the forest estimated from the size of snow cracks at the beginning of the spring thaw was investigated on the mountain slopes in Kamabuchi, Mamurogawa town, Yamagata, in north Honshu.
It seems that the accumulated snow is stable and no avalanche occurs in forests on the slope in which the number of trees n per ha is over
n=12500 (θ-30) secθ/D²
where θ : inclination (degree)
D : diameter of tree at breast height (cm)
or the volume of the stand is over 100m³ or thereabouts under snow conditions of 1.52 m in depth.