林業経営情報としてのスギ樹幹ヤング係数の利用

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.