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桦树是昭盟高山次生林区的主要防护和用材树种。据统计,现有桦林面积约800多万亩,近十多年来普遍遭受桦蛱蝶(Polyonia vaualbum Schiffermuller)的危害。1971年该虫在林西县富林林场大发生时,将桦树叶吃去40—50%,单株最大虫口密度100条,平均虫口40条/株,严重地影响了桦树的生长,给林业生产造成很大损失。鉴于该虫在内蒙古、新疆及东北各地分布普遍。1978—1980年我们对此虫进行了系统观察和防治试验,现将结果报道如下。
Birch is the primary protection and timber species of the secondary forest in Zhaomen. According to statistics, the existing birch forest covers an area of more than 800 million mu and has generally been endangered by Polyonia vaualbum Schiffermuller for more than a decade. In 1971 the insects occurred in Linlin County Forest Farm, the birch leaves to eat 40-50%, the largest single plant population density of 100, the average population of 40 insects per plant, seriously affecting the growth of birch, giving Forestry production caused great losses. In view of the insects in Inner Mongolia, Xinjiang and northeast across the distribution. 1978-1980 we conducted a systematic observation and prevention and control of insects, the results are reported below.