Rivergrass
Echinochloa polystachya

Description: Clump-forming annual grass to 80 cm high. Leaves with or without hairs, to 12 mm wide, ligule a fringe of hairs.

Distinguishing features: Distinguished by burrs 4–10 mm long with backwardly directed barbs and with ring of smaller bristles around base of burr.

Dispersal: Spread by seed in burrs. Burrs are spread attached to animals, clothing and bags, and burrs float and are moved by water.