Flora of North America species comparison

10-170 cm.

4-230 cm tall, erect or decumbent, sometimes swollen at the base, not branching above the base.

more or less evenly distributed, glabrous;

sheaths open for most of their length, uppermost sheaths often somewhat inflated;

auricles absent;

ligules hyaline, glabrous, truncate to acuminate, entire or lacerate;

blades usually flat, sometimes revolute.

2-20 cm long, 0.6-1.5 cm wide, cylindrical, discontinuous, sometimes lobed;

branches sometimes evident, spikelets borne singly, not clustered.

terminal panicles, sometimes spikelike, ovoid to cylindrical, dense, sometimes interrupted, with 10-200 spikelets borne singly or in clusters, spikelets homogamous in species with single spikelets, heterogamous in species with spikelets in clusters, lower spikelets in the clusters usually staminate, rarely sterile, terminal spikelets bisexual or pistillate.

homogamous, with 3 florets, terminal floret bisexual;

disarticulation above the glumes, beneath the sterile florets.

pedicellate, laterally compressed, with 1-3(4) florets, the terminal or only floret usually sexual, lower floret(s), if present, sterile;

disarticulation above the glumes, beneath the sterile florets in species with solitary spikelets, in species with clustered spikelets usually at the base of the spikelet clusters, sometimes beneath the bisexual or pistillate spikelets.

2-6 mm long, 0.6-1.1 mm wide, rectangular, often purplish, keels winged, scabrous, wings about 0.4 mm wide, smooth, lateral veins conspicuous, scabrous, apices mucronate;

sterile florets 2, equal, 0.5-1.5 mm, linear, sparsely and inconspicuously hairy;

bisexual florets 2-3.8 mm long, 0.9-1.5 mm wide, laterally compressed, hairy, particularly distally, shiny, apices tapering;

anthers 0.5-1.3 mm.

subequal, exceeding the florets, 1-5-veined, keeled, keels often conspicuously winged;

lower (sterile) florets reduced, varying from knoblike projections on the calluses of the bisexual florets to linear or lanceolate lemmas less than 3/4 as long as the bisexual florets;

terminal florets usually bisexual, in the lower spikelets of a spikelet cluster the terminal florets pistillate or staminate, rarely sterile;

lemmas of terminal florets coriaceous to indurate, shiny, glabrous or hairy, inconspicuously 5-veined, acute to acuminate or beaked, unawned;

paleas similar to the lemmas in length and texture, enclosed by the lemmas at maturity, 1-veined, mostly glabrous, veins shortly hairy;

lodicules absent or 2 and reduced;

anthers 3;

ovaries glabrous;

styles 2, plumose.

shorter than the lemmas, concealed at maturity, with a reticulate pericarp, falling free of the lemma and palea;

hila long-linear, x = 6, 7.

4-7 mm, truncate to rounded or obtuse, lacerate;

blades 3-15 cm long, 2-12 mm wide.

= 14.