光照对于苗木生育有密切的关系。苏联和国内都有试验报告,例如苏联试验橡树幼苗光照的结果,在四个月不断光照的橡树苗,移植於平地,经过4年的生长,结果和9年生的橡树相同。这对于造林事业有着重大的意义。因此,选定几种经济较高的树种幼苗进行光照初步试验,藉以了解这些树种对于光照条件的要求,以作今後进一步试验研究。一.材料和方法供试树种3个:(一)杜仲 Eucommia ulmoides,(二)水杉 Metasequaia Glyptostroboider, Light for nursery stock birth are closely related. Test reports were reported in the Soviet Union and in the country, such as the results of Soviet trials of the light of oak seedlings, the continuous emergence of four-year-old oak saplings transplanted to the ground for four years and the same results as the nine-year-old oak trees. This is of great significance to afforestation. Therefore, we selected several seedlings of higher economic tree species to carry out preliminary experiments of light, in order to understand the requirements of these species for light conditions for further experimental study. I. Materials and methods Three species tested: (a) Eucommia ulmoides, (two) Metasequaia Glyptostroboider,