近日,笔者在微信朋友圈里看到一张照片:一株北美海棠树干弯曲,树冠偏向一边,像一个弯腰塌背的老人。笔者结合自己的实践经验,谈谈导致北美海棠出现弯腰现象的原因。发生弯曲的北美海棠树干不是很粗,目测米径大概有2~3cm左右,树干中下部没有枝条,所有的枝条集中在树干顶部,给人头重脚轻的感觉。笔者认为,主要原因是树干顶部枝条较多, Recently, I saw in the circle of friends in WeChat a photo: a Begonia Begonia trunk bending, crown to one side, like a bent over the old man. The author combined his own practical experience, talk about the reasons leading to North American Begonia bent over. Curved North American crabapple trunk is not very thick, visual diameter of about 2 ~ 3cm, no branches in the lower part of the trunk, all the branches concentrated in the top of the trunk, give top-heavy feeling. The author believes that the main reason is the top of the trunk more branches,