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杨树是我省平原地区造林的主要树种。它具有速生丰产的特点,栽培比较广泛。近年来,由于杨树病虫害发生较重,对杨树的发展威胁很大,下面介绍杨树几种主要蛀干害虫及其防治方法。 1.杨干象虫 是国内检疫害虫之一,主要以幼虫在韧皮部中环绕树干蛀道,外观呈刀砍状切痕,破坏树木输导组织,造成树木枯梢或死亡,对三、四年生的幼树危害较大。防治应抓住
Poplar is the main afforestation species in the plains of our province. It has the characteristics of fast growing, more extensive cultivation. In recent years, poplar pests and diseases due to heavy occurrence, the threat to the development of poplar is very large, the following describes several main types of poplar stem borer pest and its prevention and treatment methods. 1. Yang dry as insects is one of the domestic quarantine pests, mainly larvae in the phloem around the trunk of the tunnel, the appearance of a knife-cut incision, damage to the organization of the trees, causing trees dead or dead, three or four years of young Trees are more harmful. Prevention should seize