Plants perennial; cespitose, not rhizomatous. Culms 15-250 cm, often disarticulating at the first node, basal internodes persistent, often swollen and clavate. Leaves mostly basal; ligules of hairs; blades flat or convolute, eventually disarticulating from the sheaths. Inflorescences terminal, panicles, not plumose. Spikelets laterally compressed, with (1)2-5 florets; rachilla prolonged beyond the distal florets, terminating in a rudimentary floret, internodes 1/3-1/2 as long as the florets, glabrous; disarticulation beneath the florets. Glumes exceeded by the florets, 1- or 3-veined; calluses 0.1-0.3 mm, blunt, glabrous or sparsely strigose, hairs to 0.5 mm; lemmas glabrous, inconspicuously 3(5)-veined, rounded over the back, acute to obtuse, unawned; paleas subequal to the lemmas; anthers 3. Caryopses falling free from the lemmas and paleas; pericarps loosely adherent. x = 9. Named for Juan Ignazio Molina (1740-1829), a Jesuit missionary and botanist, and the author of the first comprehensive summary of Chilean plants.
Spikelets 2-4-fld, disarticulating above the glumes and between the lemmas; uppermost floret reduced or abortive; glumes subequal, shorter than the lemmas, the lower 1-veined or veinless, the upper 1-3-veined; lemmas chartaceous, rounded on the back, not scarious, obscurely 3-veined; palea about equaling the lemma; rachilla-joints elongate; densely tufted grasses with long flat blades and elongate upper internodes, bearing a slender panicle; ligule a row of hairs. 2-3, temp. Eurasia.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.