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一、危害情况:杨干白尾象(虫甲)是我省主要害虫之一,对杨、柳、桦等幼树有毁灭性的危害,是森林植物检疫对象。我场的德隆地、兴隆庄等杨树人工林被害最严重。杨干白尾象虫甲主要危害青杨、加拿大杨、小叶杨和青皮柳,其中以小青杨被害最重。从一九六五年开始对此虫进行了观察和防治试验。据历年来的观察在幼虫阶段对树木危害最重,幼虫在树干的皮层内取食危害,因此,不易发现,2～3命幼虫在边材处危害,咬成不规则的浅坑.3命以后的幼虫开始蛀入木质部,自上或向下蛀
First, the damage: Yang dry white tail elephant (insect) is one of the major pests in our province, Yang, Liu, birch and other young trees have devastating hazards, is the object of forest plant quarantine. My field of Delong, Xinglong village and other poplar plantation was the worst. Yang dry white tail bug insects A main hazard Poplar, Canada poplar, Populus and green blue willow, of which the young Populus was the most victims. The worm was observed and controlled from 1965 onwards. According to the observation over the years in the stage larvae most damaging to the trees, the larvae feeding in the cortex of the tree trunk damage, therefore, not easy to find, 2 to 3 life-threatening sapwood in the sap, bite into irregular shallow pit .3 life After the larvae began to erode xylem, since the moth or down