Poa subg. Poa
Plants annual or perennial; sometimes unisexual; with or without rhizomes or stolons, densely to loosely tufted or the culms solitary. Basal branching intra- and/or extravaginal or pseudointravaginal. Culms spindly to stout, terete or weakly to strongly compressed; nodes 0-5, exserted. Sheaths terete or weakly to strongly compressed, closed only at the base or up to full length, fusion of the margins not extended by a hyaline membrane, basal sheaths usually glabrous, rarely sparsely retrorsely strigose, hairs about 0.1 mm; ligules 0.1-18 mm, thinly membranous and white to milky white or hyaline, truncate to acuminate, entire or erose to lacerate, smooth or ciliolate; blades flat, folded, or involute, thin to thick, smooth or sparsely to densely scabrous, adaxial surfaces glabrous or hairy, hispidulous or puberulent, apices narrowly to broadly prow-shaped. Panicles 1-41 cm, erect to nodding or lax, tightly contracted to open, with 1-100+ spikelets; branches 0.5-20 cm, erect to reflexed, terete or angled, smooth or sparsely to densely scabrous, usually glabrous, rarely hispidulous, with 1 to many spikelets. Spikelets 2-12 mm, subterete to strongly laterally compressed, sometimes bulbiferous; florets (1)2-8(13); rachilla internodes smooth or scabrous, glabrous or pubescent. Glumes shorter than to slightly exceeding the adjacent lemmas, weakly to distinctly keeled, smooth or scabrous; calluses blunt, usually terete or slightly laterally compressed, sometimes slightly dorsally compressed, glabrous, dorsally webbed, diffusely webbed, or with a crown of hairs; lemmas 1.7-11 mm, rounded to weakly or distinctly keeled, thinly membranous to chartaceous, glabrous or hairy on the keel and veins, sometimes the intercostal regions also hairy, 5-7(11)-veined, margins smooth or scabrous, glabrous, apices obtuse to acuminate; palea keels usually scabrous, infrequently smooth, glabrous or with hairs; anthers (1-2)3, 0.1-4.5(5) mm.