造林密度是人工林的一个重要技术关键环节。国内外有关杨树造林密度的研究资料较多,但就我国特有杨树毛白杨造林密度的研究尚无定论。在五十年代末和六十年代初,国内一些科研、教学单位虽就这一树种的造林密度设置定位试验,但因时间短,都未取得较完整的资料。本项研究于1963年设置,并坚持了系统观察,1979年进行了全面调查。现将17 Afforestation density is an important technological link of plantation. There is a lot of research data about the poplar density at home and abroad, but the research on the afforestation density of Populus tomentosa in our country is inconclusive. In the late 1950s and early 1960s, although some research institutes and teaching units in the country have set up a pilot test on the planting density of this tree species, no complete information has been obtained due to the short time. The study was set up in 1963 and insisted on systematic observation. In 1979, a comprehensive survey was conducted. Now 17