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龙游县马尾松毛虫的发生分安全区、偶灾区和常灾区３种类型，安全区基本呈无虫状态，常、偶灾区１９８７年前每２～３年和６～７年大发生１次，１９８７年后每３～４年和６～７年有一个幅度小、时间短的虫口上升期。该县白僵病的流行是抑制松毛虫种群增长的主导因子，其次是赤眼蜂的寄生，因此，采用以营林措施为基础，生物预防为主、化学防治为辅的综合治理的是适合该县的防治策略的，１９８１～１９９４年共为松林挽回经济损失３３５６．２万元，获经济效益３０２４．５万元，同时取得了明显的生态和社会效益。
The occurrence of Masson pine caterpillars in Longyou County was divided into three types: the safe area, the disaster-stricken area and the frequently-hit area. The safety area was basically insects-free, and the frequent occurrences occurred once every 2 to 3 years and 6 to 7 years before 1987 After 1987, every 3 to 4 years and 6 to 7 years there is a small amplitude and short period of rise of the population. The prevalence of white stiff disease in this county is the dominant factor that inhibits the population growth of the pine caterpillars, followed by the parasitic Trichogramma. Therefore, the comprehensive management based on the measures of silviculture, biological prevention and supplemented by chemical control is suitable The prevention and control strategy of the county from 1981 to 1994, a total of 33.562 million yuan economic losses for the forest to restore economic benefits of 30,245,000 yuan, while achieving significant ecological and social benefits.