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我国核桃的栽培遍於华北及华东、华中的局部山区地带。所产的核桃除在国内市场自销外,主要是运销国外。每年给国家换回不少社会主义建设所需要的机器。但由於核桃黑(核桃举肢蛾幼虫)的为害,影响核桃的生产,成为华北一带发展核桃生产的一个障碍。北京京西矿区的核桃栽培是全国核桃驰名的产地,由於核桃黑的为害,每年就减产40％以上。为害严重的核桃树上,连一个好的核桃都没有。
The cultivation of China’s walnut throughout northern and eastern China, central China’s mountainous areas. The walnut produced in addition to self-sales in the domestic market, the main overseas sales. Every year, the country is required to exchange many machines needed for socialist construction. However, due to the damage caused by walnut black (wallaby moth larvae) and the production of walnut, it has become an obstacle to the development of walnut production in North China. Beijing Jingxi mining walnut cultivation is well-known origin of the country’s walnut, due to the damage of walnut black, annual reduction of 40% or more. Harmful walnut trees, not even a good walnut.