The tea bush or tree is a member of the natural order Ternstroemiaceae and is closely allied to the well-known ornamental shrub the camellia. Cultivated in China, it is an evergreen shrub growing to a height of from three to five feet. The stem is bushy, with numerous and leafy branches; the leaves are alternate, leathery in texture, elliptical, obtusely serrated, strongly veined and placed on short-channelled footstalks. The flowers are white, axillary and slightly fragrant. The fruit is a woody capsule of three cells, each containing one large nearly spherical seed, which consists mainly of two large hemispherical cotyledons.

The teas of commerce are derived almost entirely from the varieties Viridis and Bohea. The Assam Indigenous, in its two sub-races of Singlo and Bazalona, and the Manipur, originally found wild in the jungles of the native state of that name, have, with various intermixtures and crossings, been used to cover the greatest areas of all the more modern planting in India, Ceylon and Java.

Constant controversy has existed as to what is the actual original home of the tea plant, and probably no one has given to the subject more careful study than Professor Andreas Krassnow of Kliarkoff University. By order of the Russian government, he visited each of the great tea-growing countries, and the results of his observations were published in a book titled "On the Tea-producing Districts of Asia." He holds the opinion that the tea plant is indigenous, not to Assam only, but to the whole monsoon region of eastern Asia, where he found it growing wild as far north as the islands of southern Japan.