Eleusine tristachya

Tufted or shortly rhizomatous perennial or annual, culms spreading to erect, to 30(–50) cm high. Leaves glabrous or nearly so; blade smooth to somewhat scabrous, flat to folded, to 20 cm long and 5 mm wide; ligule c. 0.5 mm long. Inflorescence usually quite terminal, rarely with a reduced spike shortly below the umbel. Spikelets 4–10-flowered, 4–9 mm long; lower glume 1-nerved, broadly acute to obtuse, 1.5–2.5 mm long, weakly keeled, upper glume 3–5-nerved, acute, 2.5–3.5 mm long, strongly keeled; lemma resembling upper glume but slightly longer and 5–7-nerved; seed papillose, and obliquely ridged, c. 1 mm long. Flowers Dec.–Apr.