前言本项试验是1980年参加由中国林科院林研所主持的全国白榆种源研究协作课题,1983年列入区内白榆种源试验研究。区内在呼市、乌盟、伊盟三处组织了二级白榆区域协作试验。六年来已看出不同种源苗期到幼林 Preface This experiment is to participate in 1980 by the Chinese Academy of Forestry Lin Institute presided over the national elm provenance research collaboration topics, in 1983 included in the region elm provenance research. In Hohhot, Uygur and Iraqi Armed Regions, the second grade elm region collaborative experiment was organized in the area. Six years have seen different provenances seedling to young forest