Flora of North America species comparison

55-100 cm, not forming corms;

internodes smooth, basal internodes not thickened.

(4)9-250 cm, sometimes forming a basal corm;

nodes and internodes usually glabrous.

often scabrous on the keels, otherwise smooth;

ligules 1-7 mm;

blades 2-5 mm wide, both surfaces glabrous, scabridulous.

closed almost to the top;

auricles sometimes present;

ligules thinly membranous, erose to lacerate, usually glabrous, those of the lower leaves shorter than those of the upper leaves;

blades flat or folded, glabrous or hairy, particularly on the adaxial surfaces, sometimes scabrous.

13-25 cm;

branches 1-9 cm, straight and appressed or flexible and ascending to strongly divergent, with 1-12 spikelets;

pedicels sharply bent below the spikelets;

disarticulation below the glumes.

terminal panicles;

primary branches often appressed;

secondary branches appressed or divergent;

pedicels either more or less straight or sharply bent below the spikelets, scabrous to strigose distally;

disarticulation below the glumes in species with sharply bent pedicels, above the glumes in other species.

8-16 mm long, 1.5-5 mm wide, parallel-sided when mature, with 2-5 bisexual florets;

rachilla internodes 1.9-2.1 mm.

with 1-7 bisexual florets, terminating in a sterile structure, the rudiment, composed of 1-4 sterile florets;

rudiments sometimes morphologically distinct from the bisexual florets, sometimes similar but smaller.

green, pale, or purplish-tinged;

lower glumes 3.5-6 mm long, 2-3 mm wide, 3-5-veined;

upper glumes 5-8 mm long, 2-3 mm wide, 5-veined;

lemmas 6-10 mm, glabrous, chartaceous on the distal 1/3, 5-11-veined, veins conspicuous, apices rounded to acute, unawned;

paleas about 2/3 the length of the lemmas;

anthers 1-2.5 mm;

rudiments 1.8-5 mm, acute to acuminate, resembling the bisexual florets.

membranous or chartaceous, distal margins wide, translucent;

lower glumes 1-9-veined;

upper glumes 1-11-veined;

calluses glabrous;

lemmas membranous basally, sometimes becoming coriaceous at maturity, glabrous or with hairs, (4)5-15-veined, usually unawned, sometimes awned, awns to 12 mm, straight;

paleas from 1/2 as long as to almost equaling the lemmas, keels usually ciliate;

lodicules fused into a single, collarlike structure extending 1/2 - 2/3 around the base of the ovaries;

anthers (2)3.

usually 2-3 mm, smooth, glabrous, longitudinally furrowed, falling from the floret when mature, x = 9.

= 18.