Extraction and analysis of paclitaxel and other taxanes in bark, needle leaves and stem segments of male and female plants of Taxus wallichiana, representing several populations, indicate that significant variation in taxane content exists within the population. Bark accumulated maximum amount of paclitaxel in almost all plants. Populations located at higher altitude tended to accumulate more paclitaxel than lower altitude plants. Seasons in which samples were collected and plant age have also been shown to affect paclitaxel accumulation. No effects of plant sex on paclitaxel content of the plants analyzed were observed. Significant differences in baccatin-III and 10-deacetylbaccatin III content were found to exist in the trees analyzed in this study.