Cenchrus echinatus is a species of grass known by the common names southern sandbur, spiny sandbur, southern sandspur, and in Australia, Mossman River grass.It is native to North and South America. t is a clump-forming annual grass growing up to 80 cm tall. The leaves occur with or without hairs and measure up to 12 mm wide. The ligule is a fringe of hairs. The grass has barbed burrs of 4–10 mm long.