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落叶松尺蠖(Erannis ankeraria)是落叶松的重要害虫。最近两年,我省围场县落叶松尺蠖大发生,1983年被害松林达40余万亩,虫口密度最高达20,000头/株以上,数万亩松林树叶被吃光。6月下旬至7月上旬,我们在被害松林发现落叶松尺蠖大量自然死亡,经室内检查,为核型多角体病毒病所致。据7月上旬初步调查,落叶松尺蠖核型多角体病毒病发生范围很广,在龙头山林场、塞罕坝机械林场各个分场的林地,均见到自然发
Larix spp. (Erannis ankeraria) is an important pest of larch. In the last two years, the Larix principis-rupprechtii in Weichang County of our province took place. In 1983, more than 40 million mu of pine forests were harmed and the density of insect pests reached as high as 20,000 heads / plant. Tens of thousands of mu of pine-tree leaves were eaten. From late June to early July, we found a large number of natural deaths of Larix kaempferi in the pine forests. After laboratory examinations, we found nuclear polyhedrosis virus disease. According to a preliminary survey in early July, Larix olgensis nuclear polyhedrosis virus disease occurs in a wide range of forest in Longtoushan Forest Farm and Saihanba Machinery Forest Farm, all saw natural hair