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我省南北树种各异,森林病虫种类繁多,每年成灾面积在250—320万亩之间,虽经连年防治,但未从根本上解决问题。为了澄清原因,探索有效防治方法。现将有关调查材料整理述后,供作参考。 1.大面积纯林是导致病虫成灾的根本原因。我省大别、桐柏山区有天然马尾松次生林300余万亩,松毛虫在历史上连年间歇成灾。解放后,虽经大规模防治,但仍未达到长期控制灾害的目的。主要原因是林相单纯,植被单一,害虫迁徙蔓延无阻,所到之处都有广泛而又丰富的食料,易于完成世代,加上繁殖量大,适应性强。因而灾害此起彼伏,绵延不断。据1979年4月在信阳县柳林湃河港、董家河三个公社调查,马尾松纯林每株平均
Different types of trees in the south and north of our province, a wide range of forest pests and diseases, the annual disaster area of 250-320 acres, although after years of control, but did not fundamentally solve the problem. In order to clarify the reasons, to explore effective methods of prevention and treatment. The survey materials will be sorted out for reference. 1. A large area of pure forest is the root causes of disease and insect disaster. Dabie, Tongbai mountainous area has more than 300 acres of natural Pinus massoniana secondary forest, pine caterpillars in the history of successive years of disaster. After the liberation, despite the large-scale prevention and control, the purpose of long-term control of the disaster has not yet been reached. The main reason is the simple forest, single vegetation, pest migration unobstructed everywhere to have a wide range and abundant food, easy to complete the generation, with a large breeding volume, adaptability. So the disaster one after another, endless. According to April 1979 in Xinyang County Li Lin Pai River port, Dongjiahe three communes survey, Masson pine average per plant