Camellia sinensis is the species of plant whose leaves and leaf buds are used to produce Chinese tea. It is of the genus Camellia, a genus of flowering plants in the family Theaceae. White tea, green tea, oolong, pu-erh tea and black tea are all harvested from this species, but are processed differently to attain different levels of oxidation. Kukicha (twig tea) is also harvested from Camellia sinensis, but uses twigs and stems rather than leaves. Common names include tea plant, tea tree, and tea shrub. There are two major varieties used for tea, Chinese tea, Camellia sinensis var. sinensis, and Assam tea, Camellia sinensis var. assamica. The name Camellia is taken from the Latinized name of Rev. Chinese Camellia sinensis is native to mainland China, South and Southeast Asia, but it is today cultivated across the world in tropical and subtropical regions.