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Tea Plant

Camellia sinensis (L.) Kuntze

Comprehensive Description

    Comprehensive Description
    provided by EOL staff

    The widely consumed beverage we know as tea is made from the leaves of Camellia sinensis. This evergreen shrub or small tree originated near the source of the Irawaddy River (in Burma), then spread eastward into southeastern China and westward into upper Burma and Assam (northeastern India) (this history explains the development of the distinct China and Assam tea types). Tea has been consumed as a beverage in China for 2000 to 3000 years. It was introduced to Japan around 600 A.D. and to Europe in the 1600s. Tea is grown mainly in the subtropics and in the mountainous areas of the tropics between latitudes 41° N and 16° S. It is an intensively managed perennial monoculture crop cultivated on large- and small-scale plantations in a variety of countries including China, India, Sri Lanka, Kenya, Turkey, Vietnam, and Indonesia. Overall, tea is grown on over 2.71 million hectares in more than 34 countries across Asia, Africa, Latin America, and Oceania, with an annual yield of 3.22 million metric tons of processed tea. A tea bush may be harvested for 40 to 50 years (in some cases up to a century). Harvest involves plucking the terminal bud and the 2 or 3 leaves immediately beneath it. (Vaughan and Geissler 1997; Hazarika et al. 2009)

    The economies of many tea-growing countries are heavily dependent on tea. Among the greatest challenges faced by tea growers is damage from insect and mite pests, which typically cause losses on the order of a tenth to a half of yield, and can sometimes result in total crop loss. The annual value of yield loss to arthropod pests has been estimated at U.S. $500 million to $1 billion. Hazarika et al. 2009 reviewed the biology of arthropods known to feed on one or more parts of the tea plant, as well as the history of attempts at chemical control with organosynthetic pesticides and prospects for more effective and ecologically sustainable approaches to minimizing losses to pests in the future. (Hazarika et al. 2009 and references therein)

    Around 75% of the world's tea production is black tea, which is produced by drying, macerating, and "fermenting", or faciliating the oxidation of, the leaves (this "fermentation" process does not involve microorganisms). Green tea production, which is concentrated in China and Japan, does not involve a fermentation process. Oolong tea (or Wulong Tea) is partially fermented. Some herbal "teas" contain no actual tea, making them caffeine-free. (Vaughan and Geissler 1997)