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松毛虫是河北省的主要森林害虫,初步调查有赤松毛虫(Dendrolimus SpectabisButler)、油松毛虫(D.tabulaeformis Tsai et Jiu)和落叶松毛虫(D.SuperansButler)。由于松毛虫繁殖力强,危害严重,给林业生产带来很大损失。近几年来,各地的防治手段逐步提高,特别是生物防治已被人们所认识,看到了自然界既有危害松林的松毛虫,又有抑制松毛虫灾害的天敌。为了提高生物防治水平,选择松毛虫天敌的优良种型,加以保护和利用。我们于7月下旬至8月上旬的松毛虫卵期,分别到丰宁、兴隆、青龙、平
Dendrolimus is a major forest pest in Hebei Province. Preliminary investigations include Dendrolimus Spectabis Butler, D. tabulaeformis Tsai et Jiu and D.SuperansButler. As pine caterpillars reproductive power, serious harm to forestry production has brought great losses. In recent years, the means of prevention and control have gradually increased everywhere. In particular, the biological control has been recognized by people. The natural world has both the pine caterpillars that endanger the pine forests and the natural enemies that suppress the pine caterpillars. In order to improve the level of biological control, choose the excellent species of pine caterpillar natural enemies to be protected and utilized. We are in late July to early August of the pine caterpillar egg period, respectively, to Fengning, Xinglong, Qinglong, Ping