The aim of this study is to organize the techniques for long term forest management and put the vanishing technique on record by examining the existing technique in Yoshino. We obtained by hearing the criteria of thinning tree selection and Mr. Tadakazu Arizuka's autobiography who is one of 'Yamamori' forester working at sugi and hinoki plantation at Sugitani in Higashiyoshino. As the results, it is clear that he found fun and something to work for and was responsible for his work. He learned about some of techniques by his leaders and he kept working for a long time. His criteria of thinning tree selection are; 1. 'To keep good tree formation. (He would like to keep forest high quality.) 2. To watch the tree canopy. (By doing so, he decides which tree is to be thinned.) 3. To cut the tree standing at the upper side of the hill. (Such trees will disturb the growth of ones standing at lower.)