集安县郊区公社通沟大队苗圃八一年插穗育苗,八二年准备留床育二年生苗。在起苗时发现被压的,木质化不好的苗木,完全是杨条上部的插穗。而杨条中部的插穗苗木生长的比较高和粗。为了进一步探讨其原因,我们在八二年对72个杨树品种,进行了按杨条上、中、下三个部位的插穗分段扦插的实验。一、扦插方法的要点杨树上部枝条过于纤弱部分,髓心所占比例较大,插入苗床后,不但成活率低,长出的 Ji’an Suburban communes through the ditch Brigade nursery cuttings nursery eighty-one years, eight two years to stay bed-fed two-year-old seedlings. When the seedling is found to be pressured, poorly lignified seedlings, is entirely cuttings on the top of Yang. The middle section of poplar seedlings growth is relatively high and crude. In order to further explore the reasons for this, we conducted 72 poplar varieties in August in 2002, according to the top, middle and lower parts of the cuttage cuttings experiments. First, the main points of the cutting method Poplar branches above the part is too weak, a large proportion of medulla, inserted into the seedbed, not only low survival rate, grow