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选择刺槐优树是建立采穗圃和种子园的物质基础,它的好坏直接关系到所产条材和种子的品质。所以,优树的选择,要求在长势旺盛,林相整齐,未拔大毛,郁闭度不低于0.6,10年生以上的实生林或萌芽林林分中进行。优树标准:胸径要大于对比树的平均值的15％;树高要大于或等于对比树的平均值;主干高(指由地面至树干分叉并突然变细处)不低于树全高的60％;干型比较通直圆满,树冠匀称;无病虫害。
Choosing acacia tree is the material basis to establish scion garden and seed garden. Its quality is directly related to the quality of the produced strips and seeds. Therefore, the choice of superior trees requires vigorous growth, neat forest, not pull big hair, canopy density of not less than 0 6, 10 years old or more forest or sprout forest stand. Excellent tree standard: the diameter at breast height should be greater than 15% of the average of the comparison tree; the height of the tree should be greater than or equal to the average value of the comparison tree; the height of the trunk (bifurcation from the ground to the trunk and abrupt thinning) 60%; dry type more straight, crown symmetry; no pests.