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我国已发现的森林病虫害有8000多种,其中对林木造成严重危害的有200多种。仅松毛虫危害的马尾松林面积,湖南、湖北、江西、广西等南方省区去年就达2000多万亩。因此,坚持早疫防、早发现森林病虫害的原则很有必要,现介绍如下方法: 一、叶色变化健康的森林保持固有色彩。如发现异常变色,则可能是受到什么侵害。二、叶量减少不论针叶或阔叶树,如林冠稀疏可以透视时,
There are over 8,000 kinds of forest pests and diseases found in our country, of which there are over 200 kinds of trees that cause serious harm to the trees. Only pine caterpillar harm Pinus massoniana forest area, Hunan, Hubei, Jiangxi, Guangxi and other southern provinces reached more than 2000 million mu last year. Therefore, it is necessary to insist on the principle of early-stage epidemic prevention and early detection of forest pests and diseases. The following methods are introduced as follows: First, forests with healthy leaf color maintain their inherent color. If you find abnormal discoloration, you may be subject to what violations. Second, reduce the amount of leaves Whether conifers or broadleaf trees, such as canopy sparse perspective,