一、材料来源来源于黑龙江省东方红林业局永幸林场30株初选优树材料(表1),取自年龄30～80年之间,郁闭度在0.6～0.8的山场林中.选择树干通直、无病虫害者为初选优树,然后逐项评分,满分为100分,若优树总分≥平均分数,如本例≥65分者选为复选优树,其综合得分标准是根据选优的目的和山杨的特点,做出各项规定如下:1.生长指标的评定(满分50分):当优树 First, the source of the material is from 30 primaries selected from the Yongfeng Forest Farm of Dongfang Huan Forestry Bureau in Heilongjiang Province (Table 1), taken from the mountain forests aged from 30 to 80 years and with canopy density ranging from 0.6 to 0.8. Tree trunk straight, no pests and diseases were primaries tree, and then itemized, out of 100 points, if the tree total score ≥ average score, such as ≥ 65 points in this case were selected as superior tree, the composite score Is based on the purpose of selection and the characteristics of aspen, to make the following provisions: 1 assessment of growth indicators (out of 50 points): When the tree