Abstract
Tree saplings were planted in 1977 on a slope covered by Sasa bamboo in the Teshio Experiment Forest of Hokkaido University to prevent snow avalanches occuring every year and to restore the natural landscape of the slope. Before the planting, Sasa densely covering the slope was pruned away and short wood stakes were rammed in the upper part of the slope, and saplings of Abies, Picea and two species of Larix were planted in the slope. Then the slope was protected from snow avalanches in the following years, probably by effects of sasa-clearing and wood stakes, and the growth of saplings resulted in the reestablishment of a forest stand. After 19 years of the planting, mean heights of Larix, Abies and Picea attained 12, 7 and 4 m, respectively. Avalanches on the slope never occurred from 1978 to the present. Natural broad-leaved trees such as Quercus and Tilia species, which were inhibited their growth by the avalanche, also regained vigorous growth and attained their maximum height over 7 m. Present small patches on the slope are mixed stands of conifers and braodleaved trees. An overall discussion is given on the introduction method of trees to the slope with deep snow, especially from aspects of landscape restoration and expected costs.
