Perennial, 1–3 ft. high. Culms geniculately ascending or with a prostrate base, rooting from the nodes, more or less branched, with the branches erect, terete, smooth and glabrous, the erect culms or portions of culms 7–8-noded, internodes mostly shorter than the sheaths or at any rate not long-exserted. Leaf-sheaths tight, but the lower soon slipping off the culms and inrolled, subherbaceous, shortly and often scantily pubescent at the nodes, ciliate along the outer margin, often bearded at the mouth, otherwise glabrous and smooth, striate; ligules membranous, rounded, 1/2 lin. long; blades linear-lanceolate to sublinear from a more or less narrowed base, tapering to a very fine point, 3–5 in. by 4–5 lin., flat, thin, soft, dark green, long and finely fimbriate-ciliate at the base, otherwise finely and appressedly hairy or glabrescent, slightly rough on the face and along the margins, midrib very slender, whitish and slightly prominent below, primary lateral nerves about 3 on each side, very fine. Panicles terminal on the culms and their branches, enclosed with their base in the uppermost sheath, obovate to broad-oblong in outline and very loose and open or more or less contracted, 4–9 in. long, divided up to the third, rarely the fourth degree; primary axis slender, like all its divisions terete, loosely beset with long and short silky hairs and very minutely scaberulous except downwards where it is smooth, internodes unequal from over 1 in. to a few lines; primary branches solitary or paired or in scanty false whorls, remotely divided from 1/2–1 1/2 in. from the base, finely filiform or like its divisions capillary and flexuous, the latter up to over 1 1/2 in. long, bearing 3–2 distant or only 1 spikelet, rarely again divided; pedicels short (if axes of the third or fourth order) to long or very long (over 1 in.). Spikelets broadly and obliquely obovate to semi-obovate in outline, laterally much compressed, up to 1 lin. long, dark olive-brown, very loosely scattered. Glumes very unequal, thinly membranous; lower lanceolate-acute in profile, broad-ovate if flattened out, one half to two-thirds the length of the lower floret to which it is tightly appressed, obscurely scaberulous and sparingly and minutely hairy, 3- to sub-5-nerved; upper obliquely oblong with a curved back, subacute, almost as long as the spikelet, ciliolate and loosely silkily hairy on the back, faintly 5-nerved. Lower floret: valve oblong (in profile), obtuse, very similar to the upper glume but with a straight back, 3- to sub-5-nerved; valvule more or less reduced, very narrow, 3-nerved. Upper floret hermaphrodite, almost semi-obovate or semi-elliptic, apiculate at the tip, subacute at the base, up to over 7/8 lin. long, narrowly boat-shaped, brown, minutely punctate all over; valve and valvule papery, at length subcrustaceous, the former very obscurely 5-nerved with firm very narrow margins, the latter with a narrow oblong convex back, finely and transparently winged keels and thin flaps; anthers 1/2 lin. long. Grain unknown.
