The tea plant (Thea sinensis, Camellia thea, or C. sinensis) is an evergreen related to the camellia. It is native to India and probably parts of China and Japan. In the wild it grows to about 30 feet (9.1 meters) in height, but in cultivation it is normally pruned to 3 to 5 feet (91 to 152 centimeters). Tea plants require a well-drained habitat in a warm climate with ample rainfall. The leaves are prepared by drying, rolling, and then firing. Black teas (such as pekoes), unlike green teas, are fermented before firing; oolong teas are partially fermented. Tea's stimulating properties are due to its relatively high caffeine content plus its astringency to tannin. Grown in China since prehistoric times, tea was produced on a commercial scale there by the 8th century. It was introduced into Europe by the Dutch <l:3,10>East India Company<e> in the 17th century, and its popularity helped spur the opening of Eastern Asia to western commerce. In colonial America, a tax on tea led to the Boston Tea Party in 1773. Today tea is consumed by more people and in greater quantity than any beverage except water. 
