杨树品种很多,但在河北省坝上高寒干旱地区,仅小叶杨、小青杨生长较好,分布普遍,适应性较强。加拿大杨、毛白杨、银白杨每年地上部均冻死,不能成林。河北省张北县中心林场于1957年,从河北省灵寿县引进阴杨均较其它品种表现为好,深受群众欢迎和称赞。目前在河北省坝上地区已大量育苗和造 There are many varieties of poplar, but in the arid and arid area of ​​Bashang in Hebei Province, only Populus simonii and Populus simonii grow better, with widespread distribution and strong adaptability. Poplar, Populus tomentosa, Poplar in Canada are frozen to death every year, can not become a forest. Hebei Province Zhangbei Center Forest Farm in 1957, introduced from Lingshou County, Hebei Province Yin Yang are better than other varieties, welcomed by the masses and praised. Currently in Bashang area in Hebei Province has a large number of seedlings and made