Abstract:Abstracts:The rhizome root system of Phyllostachys praecox cv. Prevernalis experimental forest was investigated and analyzed. The results showed that: ①the average value of rhizome was 5.95 segments per square,and the length of rhizome 10.8 m per four squares, and the diameter ofhizome 1.42 cm,and rhizome distribution rate was 54.7% in depth of 11~30 cm,and the rhizome from the second to forth year accounted for 67.31% of rhizome;②The robust shoots weremainly distributed from the first to 15th bamboo joint, which accounted for 80.8%;and the shootingrate was 85.1%; The robust shoots above the 16th bamboo joint accounted for 19.2%, and the shooting rate was 14.9%;③The bifurcated whip mainly concentrated from the first to 10th bamboo joint, which accounted for 66.4%; The bifurcated whip above the 11th bamboo joint was less, which only accounted for 33.6%; ④The rhizome spread upward along the slope direction accounted for 56.8% of the total, and that downward only accounted for 16.7%;⑤The site condition, soil depth, soil fertility and drainage condition were important for the rhizome diameter, bamboo shoot, shoot rate, survival rate and critical bifurcated whip, and they were positively correlated;⑥The reasonable bamboo stand density affected the population structure of bamboo aboveground and underground parts and the production of fresh bamboo shoot. Under the condition of good sites,if the standing bamboo density is 900 to 1 000 plants per 666.7 squares,the best economic and ecological benefits were archived.