Commonly grass is thought of as the short, green ground cover of lawns, but a wide variety of monocotyledonous flowering plants comprising the family Poaceae (sometimes alternatively termed Gramineae) are grasses. Nearly 10,000 species are classified in the grass family, including many economically important plants, such as corn, wheat, barley, rice, rye, sugarcane, and bamboo. Cereal grasses have been cultivated since about 8000 BC, and today the majority of farmland around the world is dedicated to their propagation. Much of the rest of the Earth is naturally covered by grasses, which grow rapidly and are well adapted for survival. Though most plants exhibit growing points at the tips of their stems, grasses possess basal meristems so that even when the upper section of a grass is lost due to grazing, fire, or cutting, regrowth may easily occur