杨树是我国北方地区主要的速树种,但生长速度不同品种有很大差异。1970年以来,我们连续5年进行了杨树杂交育种工作,选出了一些优良系号。1982年种植在林业果树研究所围墙西边的道路上。通过几年生长后看出:131表现特别速生,7年生树(包括苗龄)最大的一株胸径40.5cm,每年直径 Poplar is the main speed tree species in northern China, but the growth rate of different varieties are very different. Since 1970, we have conducted poplar hybrid breeding for five consecutive years and selected some excellent lines. In 1982 planted in the forestry and fruit trees west of the fence on the road. After several years of growth, it can be seen that: 131 has a particularly fast-growing, 40.5cm-diameter breast diameter at its 7-year-old tree (including seedling age)