Abstract:From 1987 to 1991 a survey on the rational stand density after one-time final thinning and the effect of deep soil tending orperation on the growth of Chinese fir plantation in fastgrowth phase was carried out in Dagangshanmountain, Jiangxi province. The result shows that the reasonable stand densityafter thinning should be kept at 1350 trees/ha or so on sites with a site indexof 16m in the hilly area; if a stand has a initial planting density above 2505trees/ha and no thinning afterward, it will be subjected to the risk of price.On sites with high quality class, the yield volume is maily determined by stand density while the deep soil tending has no significant effect, the increasedDBH growth by thinning is not detectable untill the second year since the DBHgrowth in the first year by thinning is not significent greater than that in theuntouched stands. It is expected that through one-time final heavey thinningthe rotation for Chinese fir can be shortened by 8 years on sites with highquality clas