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白榆生长快、材质好、分布广、适应性强,是我国常见的速生阔叶用材树种,也是甘肃绿化造林的主要树种。长期的生产实践证明,本省的白榆,普遍表现为生长缓慢、树冠扩展,干形弯曲,因而在一定程度上影响了白榆的利用和发展。苗期试验初步探讨和掌握了白榆不同地理种源生长、形态以及抗性等方面的差异。但是要选择最佳种源直接用于林业生产上,进而为种子区划提供可靠的科学依据,造林试验就显得更为重要。现将幼林初期(1982—1984年)的试验结果综述如下。
Elm grow fast, good material, wide distribution, strong adaptability, is China’s common fast-growing broad-leaved timber species, but also the main afforestation afforestation in Gansu. Long-term production practice has proved that the elm in the province, generally showed slow growth, crown expansion, dry bending, which to a certain extent, affected the utilization and development of elm. The seedling experiment initially discussed and mastered the differences in the growth, morphology and resistance of different geographical provenances of Ulmus pumila. However, it is more important to choose the best provenance to be used directly in forestry production, and then provide a reliable scientific basis for seed division. Now young early stage (1982-1984) test results are summarized below.