Indian grass, (Sorghastrum nutans), perennial grass of the family Poaceae, one of the important constituents of the North American tallgrass prairie. Indian grass is sometimes planted as an ornamental border grass and is a good forage plant for livestock. It is a close relative of slender Indian grass (Sorghastrum elliottii) and lopsided Indian grass (S. secundum).
Indian grass is a tall sod-forming plant. Its fibrous roots reach depths of down to 1.8 metres (6 feet). The upright clumping leaves are blue-green and fade to yellow-orange in the fall. The plant bears narrow, greatly branched flower clusters. Each yellow spikelet is fringed with white hairs, giving the plant a silver-and-gold appearance. It readily reseeds itself in a variety of soils and is well adapted to fire.