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博尔塔拉州和博州垦区的各团场,现有人工林近20万亩,其中85%的面积是各种杨树品种,大部分是1—3年生的幼龄树。近两年受杨毒蛾为害普遍且严重,每年有20—30%面积的杨树叶子被吃光。今春发现大量杨毒蛾的越冬幼虫上树。据4月29至5月5日在84、89团场调查,2—3年生的杨树,有虫株率为80—100%,地面至树主干2米范围内的虫口密度,每株平均在10.9头,多的
Bortala and Bozhou reclamation area of the community, the existing nearly 20 million mu of plantations, of which 85% of the area is a variety of poplar species, mostly young trees 1-3 years old. In the past two years, the damage caused by the thunbergii moth was widespread and serious, with 30 to 30% of the poplar leaves eaten each year. Spring this year found that a large number of winter moths overwintering larvae on the tree. From April 29 to May 5 in 84,89 field surveys, poplar trees aged 2-3 years had an insect population of 80-100% and a population density within 2 meters from the ground to the trunk of the tree, In 10.9 head, more