Datura is a genus of 12-15 species of vespertine flowering plants belonging to the family Solanaceae. Their exact natural istribution is uncertain, due to extensive cultivation and naturalization throughout the temperate and tropical regions of the globe, but is most likely restricted to the Americas, from the United States south through Mexico (where the highest species diversity occurs) to the mid-latitudes of South America. Some species are reported by some authorities to be native to China, but this is not accepted by the Flora of China, where the three species present are treated as introductions from the Americas. It also grows naturally throughout India and most of Australia. According to the old ayurvedic medicinal system (at least since 2000 BC) in India, this plant has versatile uses in medicinal preparations.