Zizaniopsis miliacea, commonly known as giant cutgrass or southern wildrice, is a robust perennial grass native to freshwater marshes, slow-moving streams, and the edges of ponds and lakes in the southeastern United States, extending to central Mexico. It can reach impressive heights of up to 13 feet, with stout, erect stems and broad, blue-green leaves that can be sharp-edged. The plant produces large, showy panicles of flowers that are typically greenish to purplish, blooming from late summer to early fall. The flowers are followed by grain-like seeds that resemble rice, hence the common name "wildrice".

Giant cutgrass is valued for its use in erosion control due to its extensive root system that stabilizes soil in wetland areas. It is also utilized in habitat restoration projects and can be planted along waterways to improve water quality by filtering runoff. In cultivation, it requires consistently moist or wet soil conditions and can grow in full sun to part shade. While it can be beneficial for wildlife, providing nesting sites and cover, it can also form dense stands that may outcompete other native wetland plants and be considered invasive in some areas. Care should be taken to manage its spread in cultivated landscapes.CC BY-SA 4.0