stem timber

Excellent clones are selected for Beijing, through the economical weights analysis and index selection of industrial timber properties such as volume increment, timber total density, fiber length and stem straightness. The comprehensive breeding gain of industrial timber can be higher than 20%.

经过材积生长量、木材全年密度、纤维长度、主干通直度性状经济权重分析和指数选择，为北京点选出8个优良无性系，平均综合育种增益达20%以上。

Arbors grow fast with good stem shape and good timber.

乔木的干形好、材质优良、较速生。

According to the forecast equations of biomass and stand growth, commercial timber yield table of main stand factors, stand stem and various specifications had been compiled, which were at 6 planting densities and 14~ 20 site indexes.

依据生物量和林分生长预测方程，编制了6种不同造林密度、14～20指数级林分主要测树因子、林分树干和各种规格商品材生物量的生长过程表。