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河北杨在我省黄土丘陵区分布较广,是水土保持的优良树种。为了解其生长特性,我们于1987年6月在保德、河曲两县进行了比较全面的调查。一、河北杨在我省的分布河北杨主要分布在我省吕梁山的西坡。北起右玉、平鲁县,南到大宁、蒲县,以河曲、保德县比较集中,每县的片林面积可达400—533公顷。阴坡、半阴坡及沟谷地带最多。靠其根蘖能力自然成林,面积大小不等,一般1—10公顷。垂直分布范围为800—1500米,河曲、保德多在1000—1200米。河北杨喜生于湿润、肥厚、疏松的土壤
Hebei Yang in loess hilly area of our province is widely distributed, is an excellent tree species of soil and water conservation. In order to understand its growth characteristics, we conducted a comprehensive survey in Baode County and Hequ County in June 1987. First, Hebei Yang distribution in our province Hebei Yang mainly in the western slope of Luliang Mountain in our province. North from the right jade, Pinglu County, south to Daning, Puxian, to meanders, Baode County more concentrated, each county’s forest area up to 400-533 hectares. Shady, semi-shady and valley most. By its root tillering capacity of natural forest, the size of the area, generally 1-10 hectares. Vertical distribution of 800-1500 meters, meandering, Prudential at 1000-1200 meters. Hebei Yang Xi was born in moist, hypertrophy, loose soil