Muhlenbergia angustata (J. Presl) Kunth

Densely caespitose perennials. Culms 50−100(−120) cm tall, erect, rigid, hirsute below the basal, terete nodes; usually 1 node per culm; internodes mostly glabrous and scabrous. Leaf sheaths mostly 5−18 cm long, glabrous to scaberulous above, rounded near base, lower sheaths often becoming fibrous with age; ligules 8−15 mm long, firm below, strongly decurrent, often lacerate, apex obtuse to acute; blades 15−35(−45) cm long, 2−5 mm wide, tightly involute, glabrous to scaberulous below mostly scaberulous near above. Panicles (6−)10−24(−30) cm long, 6−15 mm wide, narrow, spike-like, usually plumbeous; primary branches 0.2−2.5 cm long, erect and tightly ascending appressed, floriferous to base; pedicels 0.5−4 mm long, usually shorter than the spikelets, hispid. Spikelets 5−7(−8) mm long, plumbeous, rarely 2-flowered; glumes (4−)5−7(−8) mm long, usually as long or longer than the floret, sometimes a little shorter, lanceolate, about equal, 1-nerved, scabrous, apex acuminate, unawned, mucronate, or short-awned; lemmas (4.6−)5−6.7(−7.1) mm long, lanceolate, plumbeous, scabrous, apex acuminate, unawned, mucronate or short-awned, the awn 1−3(−4) mm long, inserted just below the apex; callus sparsely short bearded, the hairs 0.1−0.2 mm long; paleas (4.6−)5−6.5 mm long, about as long as the lemma, narrowly lanceolate, scaberulous, apex acuminate; anthers 2−3 mm long, purplish or yellowish. Caryopses 2.5−3.5 mm long, fusiform, dark reddish-brown.

Muhlenbergiacoerulea ranges throughout the Andean Cordillera from Colombia, Venezuela, Ecuador to Argentina, Peru and Bolivia.