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杨树是“三北”防护林和用材林主要造林树种。建国以来,我省杨树造林保存面积达1000余万亩,这些林木对防风固沙、解决国家和民需用材、改善自然环境都起了重要作用。但是,随着造林面积的逐渐扩大,杨树害虫的危害也日趋加重,特别是危害性的检疫害虫,给林业生产和防护效益都造成了很大损失。目前我省各种杨树检疫害虫发生面积约263万余
Poplar is the “Three North” shelterbelt and timber plantation tree species. Since the founding of the People’s Republic of China, poplar trees in our province have been preserved in an area of more than 1000 mu. These trees play an important role in windbreak and sand fixation, in solving the problems of the country and the people in need and in improving the natural environment. However, with the gradual expansion of afforestation area, the harm of poplar pests is also aggravating, especially the harmful quarantine pests, which have caused great losses in the forestry production and protection benefits. At present, various poplar quarantine pests in our province have an area of about 2.63 million