抄録
Although it is necessary to examine the dynamics of snow deposit in order to establish the avalanche prevention forest or the method of planting and tending general forest in the heavy-snow area, the most fundamental subject is the knowledge of the effect of the snow pressure upon trees. For this reason, it will be important to clarify and study the adaptability or life-form of the trees in the snow-covered environment. From such a viewpoint the investigation was carried out in northern Hokkaido.
The results are summarized as follows.
1) In the heavy-snow environment, most of trees take a form of trunk-bending near the ground (Fig. 3).
2) From the bending portion, where the trunk touches soil, new adventitious roots sprout out and support the upper portion of trunk upright.
3) With the development of the adventitious roots, the trunk recovers from the bent form to the previous upright form externally. Todomatsu (Abies sachalinensis MAST.) (conifer) is superior to Itayakaede (Acer mono MAXIM.) (leaf tree) in ability of recovering from the bent form (Fig. 2 and 3).
4) A natural tree growing on the slope in a heavy-snow area adapts itself to its environment with a suitable method. This method and life-form of trees show their ability to grow against the snow pressure.
