1977年,我所引进黑杨派新无性系进行试验,就目前四个主栽品种来说,除Ⅰ—214造林成活率较高外,其余63、72、69三个无性系都较低.为了提高造林成活率,从1978年开始,我们进行了杨树不同时期的定植试验,现将结果初报如下:材料和方法定植试验共进行七次.从1978年11月1日起到12月16日止,定植四次;1979年2月21日起到3月20日止定植三次.每次四个无性系,三个重复.定植时,每株浇水一担.3月5日定植时,采用本所苗与年前从外地调来的假植苗作对比定植. In 1977, the introduction of black poplar clones introduced by Myeong-dong led to the fact that for the four major cultivars currently, except for the high survival rate of I-214 afforestation, the remaining three clones, 63,72 and 69, were all lower. In order to improve the survival rate of afforestation, we have carried out the colonization experiment of different stages of poplar since 1978. The results are as follows: The materials and methods of colonization experiments were carried out seven times from November 1, 1978 to December March 16, planting four times; February 21, 1979 until March 20 planting three times each of four clones, three replicates. When planting, each plant watering a bear. March 5 planting When using the seedlings and transferred from the field in the years ago for the contrast planting.