Perennial, with a long slender creeping often branching rhizome; cataphylls scarious, strongly striate, early decaying down to the pubescent or villous base; distal innovations extravaginal, subterminal intravaginal growing out into fascicles of barren and flowering shoots. Culms usually more or less geniculate, ascending, or sometimes prostrate at the base, very slender, 1/2–1 ft. high, rarely much higher, glabrous, 2–4-or if the base is prostrate more-noded, lowest internodes short, terete, simple or branched below. Leaf-sheaths rather tight, the lower more or less compressed and keeled, sometimes at length slipping off the culm, glabrous or with a few spreading hairs, subherbaceous; ligules scarious, rounded, up to 2 lin. long, usually much shorter, glabrous; blades linear, tapering to a fine point, 1–4 in. by 1 1/2–3 lin., thin, green or more or less glaucous, glabrous or more or less loosely hairy. Racemes 2–9 (rarely more), sessile or bare at the base with traces of arrested spikelets, subdigitate or racemosely arranged on a very slender angular (at least upwards) smooth common rhachis 1 1/2–3 in. long, usually solitary, sometimes 2–3-nate, erect or more or less spreading, straight, flexuous or arching, very slender, 1–3 in. long, rather loose, green, variously tinged with purple, the lowest sometimes compound at the base; rhachis more or less wavy, very slender, 1/10– 1/8 lin. wide, rarely much wider, triquetrous, angles smooth or more rarely scaberulous, internodes 1–1 1/2 lin. long or here and there much longer and then the spikelets very unevenly distributed; pedicels 2-nate, finely filiform, flexuous, angular to subangular, scaberulous or almost smooth, unequal, the longer up to 1 lin. long. Spikelets loosely appressed, elliptic-oblong, acute or subobtuse, 1 lin. long, glabrous. Lower glume membranous, ovate, acute or obtuse, up to 1 1/4 lin. long; upper elliptic-oblong, acute or subobtuse, as long as the spikelet or slightly shorter, usually 5-rarely 3- or 7-nerved with the submarginal nerves faint. Lower floret: valve very similar in shape and size to the upper glume if not slightly longer, 7-nerved, nerves more or less prominent, equidistant; valvule exceeding the lodicules by their own length or shorter. Upper floret as long as the lower, chartaceous, elliptic-oblong to elliptic, shortly acute to apiculate, 3-nerved, pale to pale olive-green, at maturity shining brown, margins of valve white. Anthers 1/2 lin. long. Grain whitish, ellipsoid, up to 3/4 lin. by 3/8 lin., scutellum half the length of the grain.
