The four species of wild rice compose the genus Zizania (common names: Canada rice, Indian rice, and water oats), a group of grasses that grow in shallow water in small lakes and slow-flowing streams. Often, only the flowering head of wild rice rises above the water. True rice, genus Oryza, is also a grass; the two genera Oryza and Zizania are closely related, sharing the tribe Oryzeae. Three species of wild rice are native to North America:Northern wild rice (Zizania palustris) is an annual plant native to the Great Lakes region of North America. Northern wild rice is the state grain of the U.S. state of Minnesota.Wild rice (Z. aquatica), also an annual, grows in the Saint Lawrence River and on the Atlantic and Gulf coasts of the United States.Texas wild rice (Z. texana) is a perennial plant only found in a small area along the San Marcos River in central Texas.and one species is native to Asia:Manchurian wild rice (Z. latifolia; incorrect synonym: Z. caduciflora), is a perennial native to China.Texas wild rice is in danger of extinction due to loss of suitable habitat in its limited range and pollution. Manchurian wild rice has almost disappeared from the wild in its native range, but has been accidentally introduced into the wild in New Zealand and is considered an invasive species there.