panicum, (genus Panicum), large genus of forage and cereal grasses in the family Poaceae, distributed throughout tropical and warm temperate regions of the world. Several species, including proso millet (Panicum miliaceum) and little millet (P. sumatrense), are important food crops in Asia and Africa. See also millet.
Panicum grasses are a diverse group of plants and can be annuals or perennials. Many are tufted or have stolons or rhizomes (underground stems) and can spread vegetatively. The flowers are typically borne in dense clusters known as panicles.
Switchgrass (P. virgatum) is an erect tough perennial, 1 to 2 metres (about 3.3 to 6.6 feet) tall, that grows in clumps; its spikelets may be reddish. It is a major constituent of tall grass prairie in North America and is a valuable forage grass. It is sometimes used for erosion control because its thick rhizomes send up new plants. Witchgrass (P. capillare), a tufted annual, is a common weed in fields and disturbed areas. Its large purplish flower clusters break off and are blown by the wind.