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白榆(家榆)是落叶乔木,生长快,材质好,寿命长,分布广,适应性强,是我国常见的一种速生阔叶用材树种。为东北、华北和淮北广大平原地区“四旁”绿化、用材林、农防林、盐碱地造林的主要树种之一。过去培育2年生榆树苗一直采用截干苗移植方法,但因种种原因成苗率仅在30—50％。我们在对现行培育技术进行调查分析的基础上,从1983年开始试验,采用“截头、控制侧枝修剪法”,取得亩
Elm (Elm) is a deciduous tree, grow fast, good material, long life, wide distribution, strong adaptability, is a common species of fast growing broad-leaved timber species. For the Northeast, North China and the vast plains of Huaibei “four sides” afforestation, timber, agricultural defense forest, saline-alkali afforestation one of the main tree species. In the past to cultivate 2-year-old elm seedlings have been used truncated stem cell transplantation method, but due to various reasons into the seedling rate of only 30-50%. Based on the investigation and analysis of current cultivation techniques, we started the experiment in 1983 and adopted the method of “truncating and controlling collateral pruning”