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白榆生长快,材质好,对气候、土壤适应性强,是我省平原绿化,农田防护林带以及营造速生丰产林的优良树种。但是,由于自然和人工选择,树木个体之间的差异很大,经我院几年的选择测定,筛选出6个生长快,干形好,易繁殖,用途广的白榆优良无性系。北京15号.是从种源试验林北京种源中选出的优良单株培育而成的。主干又直又高,树皮光滑,树
White elm grow fast, good material, adaptability to climate and soil, is the province of plain green, farmland shelterbelts and to create fast-growing high-yielding tree species. However, due to the natural and artificial selection, there are great differences among individuals. After several years of selection in our hospital, six elite elite clones with fast growth, good dryness, easy reproduction and wide use have been screened out. Beijing No. 15 is from the provenance of provenances in Beijing provenances selected from the fine single plant cultivation. Trunk and straight trunk, bark smooth, tree