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一、北京杨北京杨是以钻天杨为母本,青杨为父本的人工杂交种。树形美观,生长快,在华北及东北、西北试种,生长迅速。北京市顺义县引河林场四旁植树9年生单株高22米,胸径30.3厘米,单株材积约0.8立方米;北京林研所试验林场16年生平均高20米,胸径24.2厘米,单株材积0.46立方米,每亩蓄积量30立方米,年生长量为1.88立方米。二、意大利-214 意大利-214是意大利杨树研究所选出的天然杂交欧美杨无性系,现在全世界许多国家和
First, Beijing Yang Beijing Yang Yang is drilling Tian Yang as the female parent, Qing Yang as the male parent hybrids. Tree beautiful, fast growth, in North China and Northeast, northwest try planting, rapid growth. 9-year-old single plant height of 22 cm, diameter at breast height 30.3 cm, single plant volume of about 0.8 cubic meters; Forest Institute Beijing Institute of Forestry 16-year average of 20 meters high, DBH 24.2 cm, single volume 0.46 cubic meters Rice, 30 cubic meters per acre volume, the annual growth of 1.88 cubic meters. Second, Italy -214 Italy -214 is selected by the poplar Institute of Italy natural hybrid European and American poplar, and now many countries in the world and