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一、松毛虫分布及危害: 我省发生的松毛虫,有赤松毛虫、油松毛虫两种。油松毛虫分布于易县、遵化、平泉、迁西及迁安的西部;赤松毛虫分布于抚宁、秦皇岛市、昌黎、丰润及迁安的东部。两种通称松毛虫,发生、发展规律和防治方法相同。危害油松、赤松、黑松等针叶树种。初孵化的幼虫,仅能啃针叶边缘,不能将针叶咬断,二令幼虫能将钎叶咬断。末令幼虫食量大,占总食叶量的百分之八十。雌性幼虫
First, the distribution and damage of pine caterpillars: Dendrolimus occurred in our province, there are red caterpillar, two kinds of pine caterpillar. Pine oil caterpillars are distributed in Yixian, Zunhua, Pingquan, Qianxi and Qian’an west; red caterpillars are distributed in Funing, Qinhuangdao, Changli, Fengrun and the east of Qian’an. Two kinds of commonly known as pine caterpillars, occurrence, development and control methods. Endanger pine, red pine, black pine and other conifer species. The first hatch larvae, can only chew coniferous edge, can not be bitten off, two orders larvae can bite off the brazier. Last larvae food intake, accounting for eighty percent of the total amount of leaves. Female larvae