During intense earthquake activity and subsequent fires, urban parks become natural areas of shelter. Shortly after the great Kanto earthquake in 1923 , many parks and some residential gardens in the Tokyo area were described and assessed for fire damage by Kawada & Yanagida (1923) and Tanaka (1923). They assessed the areas as to their relative safty and the fire resistance of tree species which was indicated by the leaf susceptibility to fire. In this study, ten of these parks were selected as presentative and compared to data that was published 65 years ago by Kawada & Yanagida (1923) and Tanaka (1923). Within each park, the distribution of all tree and shrub species and the structure of forest zones were surveyed in detail. From this initial survey, Hibiya park was studied in depth. Data were collected in both summer and winter in order to determine the differentiation of seasonal fire resistance. Fire resistance map was drawn for Hibiya park. This map was used to assess the safety and general susceptibility of this park to fire.

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A large scale of forest fire has happened in Kamaishi peninsula, Iwate Prefecture, on April, 1987, by which a great deal of manmade Sugi forests were burned or damaged. There were 3 types in the forest fire; canopy fire, stem fire, and forest floor fire. In case of canopy fire or severe stem fire, damaged trees were killed perfectly. While, in case of forest floor fire, it was very difficult to estimate accurately about the future condition of damaged trees. Because, Sugi trees are not always die immediately after their stem was scorched. Basing on the after-2-years' condition of damaged trees, such as dead tree, weakened tree and healthy tree, the authors discussed the relationships between scorched degree and the fate of damaged trees, with use of several kinds of index from various parts of scorched stem, shown by figure-1. As the result of that, they could find the possibility of accurate estimation with some indexes, such as the ratio of scorched area to the total surface area in the foot part of damaged trees (S'/So') , that of scorched length to the girth length in the ground level of damaged trees (Cb/Co) and that of scorched area to the girth length of breast height (S+S'/C_<BH>) or to the girth length in the half of scorched height on stem (S+S'/C).

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