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我县位于河南省西北部,素称“白榆之乡”。全县共有白榆280余万株,占四旁植树总株数的34％。但长期以来,采用混杂种子造林,缺乏科学管理,造成品质低劣、干形弯曲,以致林木生长率、木材利用率较低。据调查,单株年均胸径生长0.98cm,单株材积0.015m~3,主干通直率仅20％左右,加之近年来榆树病虫害严重,大大挫伤了群众栽植白榆的积极性。为了提高白榆生产能力,改变
My county is located in northwestern Henan Province, known as “elm township.” There are altogether more than 2.8 million elm in the county, accounting for 34% of the total number of trees planted on four sides. However, for a long time, the use of mixed seed reforestation, lack of scientific management, resulting in poor quality, dry bending, resulting in the growth rate of trees, timber utilization is low. According to the survey, the average annual DBH growth of 0.98cm, single plant volume 0.015m ~ 3, the backbone of the pass rate of only about 20%, combined with serious diseases and pests in elm trees in recent years, greatly hurt the enthusiasm of the people planted elm. In order to improve the production capacity of elm, change