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目前山楂的产量较低,其中原因之一是不修剪,任其生长,这样到了盛果期,树体结构明显地暴露出三大矛盾。其一是大枝(主枝和辅养枝)多。据北京十三陵果园调查,平均每株树有大枝14.4个,多者达20个。第一层平均有主枝8.7个,最多13个,它们密挤轮生,把大量小枝挤垮,造成大小枝之间的矛盾。其二是外围枝密。据调查,主枝头以下30厘米长的一段距离内,平均有结果母枝37.2个,最多达52个,高度密集,相互排挤、竞争,影响冠内光照,造成外
At present, the production of hawthorn is lower, among which one of the reasons is that it is not pruned and allowed to grow. In this way, the tree structure clearly reveals three major contradictions. One is the big branch (main branch and supporting branch) and more. According to the investigation of the Ming Tombs orchards in Beijing, there are 14.4 large branches per tree on average, up to 20 more. On the first floor, there are an average of 8.7 main branches and a maximum of 13 branches. They are crowded and swollen with lots of branchlets, resulting in contradictions between branches. The second is the peripheral branch density. According to the survey, within a distance of 30 centimeters below the main branch, there are on average 37.2 mother trees, up to 52, highly densely crowded, competing and affecting the crown light, resulting in