Flowering bamboo groves can be renewed by sexual or asexual rejuvenation. In genus Phyllostachys, some species with a lof of fertile seeds after flowering are rejuvenated via sexual way, i.e. renewed by seedling; the rest are generally rejuvenated by vegetative process, i.e. renewed by rejuvenating rhizomes sprouted from, basal nodes of flowering culms. Because the sympodial growth appears in the seedling stage of monopodial species, the sympodial type seems to be an original characteristic. However, the chromosome numbers of most monopodial bamboo species are 36 or 48, but that of most sympodial bamboo species are 72. Therefore, monopodial bamboo species do not seem to evolve from the present sympodial bamboo species. Vegetative rejuvenation of some bamboo species can be effected by exogenous GA3.