The types of nee 1ength rotten are introduced in this paper. According to the practical experiments, the author summarize the optimal bucking method to the tree length with rotten defects.

• 本文从实际工作经验中总结出有腐朽缺陷的原条的合理造材方法，并根据了东京城林业局的实际情况，证明合理造材是提高经济效益的关键。