甘肃冷杉尺蠖生态学及防治措施研究

甘肃冷杉尺蠖在甘肃迭部林区大面积发生，危害严重。主要为害冷杉和云杉。冷杉纯林受害最重，冷、云杉混交林次之，针阔叶混交林受害较轻，该虫两年一代，隔年以幼虫于６月下旬至８月下旬为害。多年重复防治试验和大面积防治实践表明：于６月底至７月初即初龄幼虫期开始放烟，施放３次“７４１”烟剂，两次间隔期７～１０天，每公顷用１５ｋｇ烟剂，放烟点之间距离３０～５０ｍ，防治效果可达９８％以上。

A Study on the Ecology of Gansu Fir Looper and Its Control

Gansu fir looper(Bupalus vestalis konsuensis Webrli)is a serious insect pest in themost of the region in Diebu forest,Gansu province.It mainly attacks fir(Abies spp.)and spruce(Picea spp.).Fir pure forest is seriously injured by this insect; fir-spruce mixed forest comes thenext; it is not severe in coniferous and broadleaf mixed forest.This insect requires 2 years to com-plete its life cycle.Larve feed on the foliage of trees from the last ten days of June to the last tendays of August every other year.Experiments and the control of this insect indicated that use ofsmoke generators is the most effective approach.They are named“smoke generator 721”(SG741).Application of these insecticides in 7～10 day intervals during young larval stage from the end ofJune to early July gave efficacy of more than 98%. Fifteen kg per hm￣2 each time was the suitabledosage. Smoke-generating plots were separated by a space of 30～50m. Facts proved that this in-sect was on longer a serious problem in Diebu forest by using this control measure.