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建国以来,由于大面积营造人工油松、落叶松等纯林,加之综合管理较差,致使丰宁县每年有近10万余亩林分被落叶松毛虫〔Dendrolimus superans(Butler)〕为害,成灾面积达4万余亩。有的林分被其成片为害致死,生长量严重受到抑制,给林业生产带来巨大损失。为了进行有效的预测预报工作,提高防治经济效益,1987年我们在云务山国营林场对落叶松毛虫雌蛹重量与携卵粒数进行了相关分析的研究。
Since the founding of the People’s Republic of China, nearly 100,000 mu of forest stands in Fengning County have been damaged and devastated by Dendrolimus superans (Butler) annually due to large-scale construction of pure forests such as Pinus tabulaeformis and larch, and poor integrated management. An area of more than 4 acres. Some of the forest was killed by its film damage, the growth was severely suppressed, to the forestry production has brought huge losses. In order to carry out effective prediction and forecasting work and increase the economic benefits of prevention and control, in 1987, we conducted a correlation analysis on the female pupae weight and the number of eggs harvested from the pine caterpillars in Yunwu Mountain National Forest Farm.