长白落叶松木材材性株内变异

以３０年和５４年生长白落叶松人工林为样本，对木材材质性状的株内变异进行了分析。试验结果表明：（１）由树干基部至树梢，基本密度逐渐减少。管胞长度先逐渐增加。达最大值后逐渐缩短；（２）由髓心至形成层。基本密度，管胞长度迅速增大，至第２０轮后增幅变小；（３）用胸高处任一半方向的基本和管胞长度可以估算树干平均值；（４）胸高木芯法为合理的，实用的取样方法。

The Variation of Wood Properties within Individual Trees for Larix olgensis

The variations of wood properties within individual trees were studied for artificial stands of Larix olgensis at age of thirty and fifty-four. The basic density progressively decreased from the base to the top of trunks. The lengths of trachied increases progressively and become short step by step when it reaches the longest. The basic density and trachied length increases rapidly to the 20 rings from the pith to the cambium of trees. and then the increase exient become smaller. The basic density and trachied length at any radius orientation of breast height was used to estimate means of trunks. The method of timber wick is reasonable and practical sampling methods.