The burnt forest described in this paper is situated on the Gamow coast, about 4 km east of Sendai. This forest is dominated by Pinus Thunbergii which is estimated to be around 60 years old. Before the 1965 fire, there had been no logging in the forest, therefore, needles, branches and dead grasses on the forest floor were abundant. (viz. the weight of dry matter for fuels was 360-1000g per square meter). After the fire, the plant communities in the various habitats of burnt forest floor and unburnt forest floor are compared with each other. The main components of the burnt forest, herbs and grasses, are also among the abundant species of the unburnt forest. However, some spcies increased markedly after the destruction of ground cover. For example, the coverage of Amorpha fruticosa, Indigofera pseudo-tinctoria, Kummerowia striata, Ixeris dentata, Youngia denticulata and Rhacomitrium canescens increased. On the other hand, the height growth and weight growth of the apical buds of the burnt pine trees were measured. Compared with the unburnt trees, trees that were charred more than one-half of tree canopy did not resprout until the following year. By the end of the growing season, however, it was found that the growth of the apical buds of slight damaged trees had been reduced to about 30 percent of the uaburnt level. In addition, in order to estimate the probable high temperatures in the tree layer during the fire, burning tests with the pine leaves were carried out in the laboratory. Pine leaves are charred for two min. at 250℃, and the leaves are ignited for one min. at 400℃. In view of this fact, it became clear that considerable temperatures are reached in the tree layer during fire.
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