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榆树是漯河市的优良乡土树种之一。全市现有榆树二十余万株,居四旁树种之首位,分布广泛,遍布市区内和乡村。该树种适应性强,育苗容易,造林成活率高;材质柔韧坚硬,是农具、家具和建筑用材的优良树种;对防护农田、美化环境、增加肥料及饲料来源都起着重要作用。但是,从七十年代以来,特别是最近几年来,榆金花虫(榆兰金花虫占90％,榆黄金花虫占10％左右)逐步蔓延,连年成灾。据调查,漯河郊区一株六年生榆树,一代幼虫多达一万五千多头;每头幼虫一代可为害9—11片叶子;一
Elm is one of the fine native trees in Luohe City. The city has more than 200,000 elm trees, ranking first in all four species, widely distributed throughout the urban areas and rural areas. The species adaptable, easy nursery, afforestation survival rate is high; flexible and hard material, is a tool for farming tools, furniture and construction timber species; to protect farmland, beautify the environment, increase fertilizer and feed sources all play an important role. However, since the seventies, especially in recent years, Ulmus elaphus (90% of Ulmus and about 10% of Ulmus elaphus) have gradually spread and have been catastrophic in successive years. According to the survey, a six-year-old elm tree in the suburbs of Luohe has as many as 15,000 first-generation larvae; each generation of larvae can damage 9-11 leaves;