The forested area maps in 1955, 1970, 1985 and 1995 were developed based on the official terrain maps of Japan. Social situations including the rapid population increase and new town plans were also investigated, in order to understand the background of the change of forested area. This study revealed clearly the rapid change of forested area in Tama in the last 40 years.

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The forest management policy in the Japanese national forests has shifted from timber production to one that emphasizes environmental functions since 'The New Forest Practice in National Forests" was established in 1973. The objective of this study is to show how this change affects forestry practice in unit scale of forest management. The management plans in Agematsu Forest District in Kisodani from 1967 to 1997 were analyzed and compared with the practices. The results of the analysis showed that the policy of plans at the Agemastu Forest District had changed with the whole national forest. At first, felling volume was reduced because over cutting in the early 60s caused the decline of forest resources. Secondly, "The New Forest Practice in National Forests" brought about improvement of clear cutting. Thirdly, forest practices based on forest classification by its functions started in 1993. On the other hand, the problem was that practices in reality did not reflect the policy plans. Particularly, the discrepancy between the plan and the practice was significant for tending and care. This situation was attributed to claims from timber companies in the area and to the decrease of labor forces in Agematsu Forest District.

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The purpose of this study was to measure the trunk-MOE (modulus of elasticity of a tree trunk) of Cryptomeia in the forest stand and to examine its use as forestry management information. First we analyzed the relationships between the trunk-MOE measured by the tree-bending test and the tree growth factors (tree height and DBH) in the Obi-sugi (Cryptomeria japonica) young plantation stand. Then, we proposed a DBH-based thinning method to control trunk-MOE in the stand, and discussed the possible application of trunk-MOE as forest management information. There was a weak negative correlation between the DBH and the trunk-MOE in 19- and 23-year-old stands, which showed the formation of mature wood during this period and the reproductivity of the measurement. The DBH-based thinning was suggested to result in the change of the average trunk-MOE in a stand and little affect coefficient of variation of trunk-MOE. The results indicate that it might be possible to produce timber satisfying user-side demands by using the stand trunk-MOE as management information.

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