Flora of North America species comparison

20-110 cm, erect or ascending.

45-120(180) cm tall, usually less than 3 mm thick, erect.

mostly glabrous or retrorsely soft pilose, throats usually hairy;

auricles sometimes present on the lower leaves;

ligules 1-3.5(4) mm, glabrous or sparsely hairy, acute to obtuse, lacerate or erose;

blades 8-30 cm long, 1-12 mm wide, flat or becoming involute, glabrous or sparsely pilose to pubescent on 1 or both surfaces.

4-16 cm long, 2-3 cm wide, erect, open;

branches sometimes longer than the spikelets, slender, usually ascending, slightly curved or straight.

5-40 cm, lax, open or erect;

lower branches usually shorter than 10 cm, 1-4 per node, ascending to strongly divergent or reflexed, with 1-4 spikelets variously distributed.

12-20 mm, lanceolate, terete to moderately laterally compressed;

florets 5-6, bases concealed at maturity;

rachilla internodes 1-1.5 mm, concealed at maturity.

20-40 mm, shorter than at least some pedicels and branches, elliptic to lanceolate, strongly laterally compressed, not crowded or overlapping, sometimes purplish, with 4-11 florets.

smooth to scabrous;

lower glumes 4-6 mm, (3)5-veined;

upper glumes 4-7 mm, 7-veined;

lemmas 6.5-8 mm long, 3-4.5 mm wide, elliptic to lanceolate, coriaceous, backs smooth, distinctly 7(9)-veined, not ribbed, rounded over the midvein, margins scabrous, rounded, not inrolled at maturity, apices acute to obtuse, bifid, teeth shorter than 1 mm;

awns 5-9 mm, all more or less equal in length, straight, arising less than 1.5 mm below the lemma apices;

anthers 1.5-3 mm.

glabrous or pubescent;

lower glumes 7-11 mm, 3-7(9)-veined;

upper glumes 9-13 mm, shorter than the lowest lemma, 5-9(11)-veined;

lemmas 10-16(17) mm, lanceolate, laterally compressed, strongly keeled distally, usually more or less uniformly pubescent or pubescent on the margins only, sometimes glabrous or scabrous, 7-9-veined, veins usually not raised or riblike, apices entire or with acute teeth shorter than 1 mm;

awns 4-17 mm, sometimes slightly geniculate;

anthers 1-6 mm.

shorter than the paleas, thin, weakly inrolled or flat.

sheaths densely hairy, hairs stiff, often retrorse;

upper sheaths glabrous or pubescent;

ligules 1-2 mm, glabrous or hairy, erose;

blades 7-18 cm long, 1-4 mm wide, pilose on both surfaces.

= 28.

= 28, 42, 56.