Studies on the Biomass and Productivity of Eucommia ulmoides Plantation

Studies on the biomass of Eucommia ulmoides Plantation of 26～27 years old were conducted in Zunyi,Guizhou Province and Cili,Hunan Province with 20 plots,80 sampling trees and 71 leaf-surface groups.The results show that the biomass of a stand on a good site is greater than that of another on a poorer site and that on the same site condition,the trunk and branch biomass ratio increases with the increase of age,but the leaf and root biomass decreases with the increase of age,and the bark biomass keeps more stable.The root's cuticle is some 30% of the total and it can be utilized after cutting.In the same stand,the dominant tree has the maximum biomass,the middle ones the second and the suppressed ones the minimum,controlling the density of the stand and choosing the suitable site for cultivation are the two important measures to increase the yield of Eucommia ulmoides.Besides,the establishment of regression equation for each nutritions organ's biomass of individual tree can be used in practical production.