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一.前言笔杨(Populus pyramidalis Borkh.P.ni-gra var.italica Dur.)又名拿布达白杨(Lom-bardy Poplar)、美国白杨、箭杆杨、黑杨、钻天杨、塔杨等,自生于中央亚细亚现在我国江苏、浙江、湖北、陕西、甘肃、新疆、山东、河北、黑龙江等省均早已引种栽培,一般生长良好.笔杨不但对于土壤和气候等条件的选择并不十分严格,而且生长迅速,树干挺直,分
I. Introduction Populus pyramidalis Borkh.P.ni-gra var.italica Dur., Aka Lom-bardy Poplar, American poplar, arrowhead poplar, black poplar, Asclepiadis, Self-born in Central Asia At present, Jiangsu Province, Zhejiang Province, Hubei Province, Shaanxi Province, Gansu Province, Xinjiang Province, Shandong Province, Hebei Province and Heilongjiang Province all have long been introduced and cultivated in general and are generally well-developed. Not only is penny’s choice of soil and climatic conditions not very strict, And rapid growth, trunk upright, points