Straggling annual; culms 10-100 cm high. Leaf-blades 5-30 cm long, 3-15 mm wide. Inflorescences terminal and axillary, of paired racemes each 3-12 cm long, internodes and pedicels clavate, ciliate. Sessile spikelet oblong-ovate, 4-6 mm long; lower glume coriaceous and transversely ridged below, membranous above, 2-keeled along its length; upper lemma with an awn 15-20 mm long. Pedicelled spikelet resembling the sessile and on a pedicel one-third the length of the internode, or much reduced and on a pedicel equalling the internode.

Fl. & Fr. Per.: October-December.

Type: India, Koenig (BM).

Distribution: Pakistan (Punjab); tropical Asia and tropical Africa; introduced to most tropical countries.

Ischaemum rugosum is a very variable species in which the pedicelled spikelet may be large and on a short pedicel (var. rugosum) or reduced and on a long pedicel (var. segetum). Although common over much of India, it is found only occasionally in Pakistan. It is eaten by horses and cattle when young.