Abstract: We studied the biomass allocation and clonal growth characteristics of Bambusa pervariabilis × Dendrocalamopsis daii and B. rigida in Changning County, Sichuan Province. The biomass of stem was higher but those of branches and leaves lower in B. rigida than B. pervariabilis × D. daii, so B. rigida had greater nutrient assimilation efficiency. The reproduction ratio of both species did not differ. However, the degenerated shoot ratio was lower for B. rigida than B. pervariabilis × D. daii, so reproduction of B. rigida was more efficient. The rhizome length was longer for B. rigida than B. pervariabilis × D. daii, so B. rigida had faster expansion ability. The growth characteristics of new bamboo were significantly associated with quantity, size and age structure of mother bamboo in B. pervariabilis × D. daii and B. rigida forests. B. rigida had a K-strategy reproductive strategy, for strong ability to produce shoots with higher ratio of grown bamboo, and B. pervariabilis × D. daii had an R-strategy, with higher ratio of shoot production and degeneration. The numbers and diameters of new bamboo at breast height were strongly correlated with that of the mother bamboo, which could be simulated with a linear model.