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一、杨树蛀干害虫的为害、种类和分布根据几年来对华北、东北、西北、华东、华中和西南部分省(区)20多个县市进行的调查和有关资料,许多苗圃、农田防护林、四旁树木和丰产林的杨树都受到蛀干害虫的为害。北京丰台区1978年统计,90%以上的毛白杨苗木受白杨透翅蛾侵害。河北省衡水县小侯公社1976年营造的农田防护林,1982
First, the damage, species and distribution of poplar stem borer According to the survey and related data of over 20 counties in some provinces (districts) of North China, Northeast, Northwest, East China, Central China and Southwest China over the past few years, many nurseries, farmland shelterbelts , The trees around and the poplar trees in high-yield forests are all damaged by stem pests. Fengtai District, Beijing in 1978, statistics, more than 90% of Populus tomentosa Poplar seedlings infested by. Hengshui County, Hebei Province, Xiao Hou commune to create farmland shelter in 1976,