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为了明确桑天牛对毛白杨造成的危害情况，确定防治阈值，在河北省对不同虫口密度、不同树龄的９０株毛白杨进行了解析木调查分析。其结果为：桑天牛影响树木高、径和材积生长，还严重影响木材质量：研究确定了其最低防治阈值；对幼林采取全部种群治理（ＴＰＭ）对策；对成林加强修技（允许少量天牛在树冠枝上存在，但要防止其进入主干），采取综合治理（ＩＰＭ）对策
In order to clarify the harm of Morus alba on Populus tomentosa and to determine the control threshold, 90 Populus tomentosa populations with different population density and different ages were surveyed in Hebei Province. The results showed as follows: Morus alba affected tree height, diameter and volume growth, but also seriously affected the quality of wood: the study determined the minimum control threshold; young population management strategy Cerambycium exists on the crown, but to prevent it from entering the trunk), to take comprehensive management (IPM) countermeasures