1. In a volcanic district such as in Japan, there is a tendency of high moors developing on the upland of the mountain slopes. Genshi-ga-hara moor is considered to be such a case. This moor is located halfway up Mt. Furano, one of the Tokachi Volcanic mountains in the Taisetsu-zan National Park in Hokkaido. 2. The wood invasions into the moor region consist of Picea Glehnii-Sasa senanensis, community and P. Glehnii-Betula Ermani var. communis community. It is assumed that the succession of the plant community arising from the "Verlanding" in this moor will be follows : Fotamogeton subsessilifolius-P. nipponicus comm.→Carex Michauxiana-Rhynchospora alba comm.→Molinia japonica-C. Tsuishikarensis [table] 3. In this moor district there are 89 swamps of more than two meters in diameter, and most of these are the nourishing-type, thus suggesting that the whole process of "Verlanding" in the moor is rather fast. 4. The air, soil surface and the soil temperatures (at 10 cm and at 30 cm) are measured both inside the moor and in the wood invasions. The results are : a. The air temperature has no significant differences between the two places, showing that in the wood the temperature is 0.5℃ lower in the day-time, on the contrary at night it is 1.3℃ higher than that in the moor. b. The soil surface temperature in the moor is higher than in the wood, but the temperature in Sphagnum Girgensohnii and S. pulchrum growing places is lower than that in the wood. c. As to the soil temperature, the temperatures both at 10 cm and at 30 cm depth in the wood are lower than those in the moor. The temperature range at 10 cm depth is larger in the moor than in the wood, but at 30 cm depth in the moor the temperature is smaller.
