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白榆是平原绿化的主要树种,由于受榆兰金花虫危害,生长受到严重影响,防碍了这一速生优良树种的发展.为有效防治此害虫我们于一九七三—一九七九年进行了生物学观察和防治试验.现总结如下:一、为害情况榆兰金花虫的成幼虫均食叶危害.主要危害白榆.据知一九七七年北京颐和园内的大果榆也遭到此虫的严重危害.我县发生严重时,将叶肉全部食光,叶片呈网状或孔状,一片桔黄,光合作用极度减弱,使林木生长受到严重影响.
White elm is the main species of plains greening, due to the damage caused by the goldenrod of Ellen, the growth has been seriously affected, hinder the development of this fast-growing fine species.In order to effectively control this pest we in 1973 - 1979 Years of biological observation and prevention and control are summarized as follows: First, the damage situation Ulmus larvae into the larvae are eating leaves the main harm Ulmus.It is known that in 1977 the Beijing Summer Palace of fruit elm Also seriously affected by this pest.What happened in our county, all the leaves will be edible, leaves mesh or hole shape, a piece of orange, the extremely weakened photosynthesis, so that the growth of trees are seriously affected.