E. crus-galli is an annual grass, culms 30-200 cm, spreading, decumbent or stiffly erect; nodes usually glabrous or the lower nodes puberulent. Sheaths glabrous; ligules absent, ligule region sometimes pubescent; blades to 65 cm long, 5-30 mm wide, usually glabrous, occasionally sparsely hirsute. Panicles 5-25 cm, with few-many papillose-based hairs at or below the nodes of the primary axes, hairs sometimes longer than the spikelets; primary branches 1.5-10 cm, erect to spreading, longer branches with short, inconspicuous secondary branches, axes scabrous, sometimes also sparsely hispid, hairs to 5 mm, papillose-based. Spikelets 2.5-4 mm long, 1.1-2.3 mm wide, disarticulating at maturity. Upper glumes about as long as the spikelets; lower florets sterile; lower lemmas unawned to awned, sometimes varying within a branch, awns to 50 mm; lower paleas subequal to the lemmas; upper lemmas broadly ovate to elliptical, coriaceous portion rounded distally, passing abruptly into an early-withering, acuminate, membranous tip that is further demarcated from the coriaceous portion by a line of minute hairs (use 25× magnification); anthers 0.5-1 mm. Caryopses 1.3-2.2 mm long, 1-1.8 mm wide, ovoid or oblong, brownish.

Growing in wetland.