Flora of North America species comparison

(30)50-110 cm, clumped, erect, glabrous or pubescent.

5-150 cm, glabrous or pubescent, basal branching extravaginal.

open the entire length or fused at the base;

auricles absent;

ligules membranous, often erose to lacerate, sometimes ciliolate;

blades rolled in the bud.

2-3 per culm;

sheaths scabridulous or pilose;

ligules 1.5-3 mm, truncate, erose to lacerate;

blades (8.5)15-20+ cm long, (3)7-12 mm wide, flat, ascending, lax at maturity, often scabridulous.

10-30 cm long, (1)2-9 cm wide, open, nodding, green or tan, occasionally purple-tinged;

branches 2-12+ cm, most, except sometimes the uppermost, spikelet-bearing only towards the apices, with the basal (1/5)1/3-1/2 bare, filiform, flexuous, at least the lowest 1-3 whorls spreading or drooping.

terminal panicles, open and diffuse to dense and spikelike;

branches antrorsely scabrous.

6-12 mm, subsessile to pedicellate, pedicels to 2 cm, usually with 2-3 functional florets below 1-2 reduced florets;

rachilla internodes and hairs 1-2.5 mm;

disarticulation above the glumes, beneath the florets.

2.5-12 mm, usually subsessile to pedicellate, rarely sessile, laterally compressed, with 2-5 florets, reduced florets sometimes present distally;

rachillas hairy, internodes evident, prolonged beyond the base of the distal bisexual florets;

disarticulation usually initially above the glumes and beneath the florets, subsequently below the glumes, in some species initially below the glumes.

unequal;

lower glumes 0.75-2(3) mm, subulate;

upper glumes 3.5-5 mm long, shorter than the lowest florets, 2-3 times as wide as the lower glumes, widest at or above the middle, ovate or obovate, rounded to the acuminate apices;

callus hairs to 1 mm;

lemmas 5-6 mm, broadly lanceolate, glabrous, bifid, teeth to 1.3 mm, awned, awns (7)9-14 mm, arising from above midlength to just below the teeth, exceeding the lemma apices, arcuate to flexuous;

paleas shorter than the lemmas;

anthers about 1 mm.

subequal or unequal, keels scabrous, apices usually acute, unawned, often apiculate;

lower glumes 1(3)-veined;

upper glumes 3(5)-veined, lateral veins less than 1/2 the glume length;

calluses hairy;

lemmas 3-7-veined, margins hyaline, unawned or awned from above the middle with a single awn, apices usually bifid, sometimes entire;

paleas from subequal to longer than the lemmas, membranous, 2-veined, veins usually extending as bristlelike tips;

lodicules 2, shallowly and usually slenderly lobed to fimbriate;

anthers 3;

ovaries glabrous or pubescent;

styles 2.

2.5-3.2 mm, densely to sparsely pubescent.

shorter than the lemmas, concealed at maturity, elongate-fusiform, compressed, brown;

embryos elliptic, to 1/3 the length of the caryopses;

endosperm milky, x = 7.

= 42.