Flora of North America species comparison

15-60 cm, erect.

to 135 cm.

glabrous;

ligules 0.7-1 mm;

blades to 20 cm long, 2-4 mm wide, without basal hairs, glabrous or scabrous, upper cauline leaves often greatly reduced.

mostly glabrous;

ligules 0.7-1 mm, erose to lacerate;

blades to 45 cm long, to 15 mm wide, with basal hairs, otherwise usually glabrous, occasionally scabrous.

with 10-20 branches in several closely-spaced whorls;

branches 2-5 cm, spreading, with 14-18 spikelets per cm;

disarticulation beneath the glumes.

digitate, with (4)8-28 evidently distinct and easily separable branches;

branches (5)8-20 cm, flexible, usually more or less spreading, sometimes drooping, averaging 12 spikelets per cm.

with 1 bisexual and 1 sterile floret.

strongly imbricate, with 1 bisexual and usually 2 sterile florets.

0.5-0.7 mm;

upper glumes 1-1.5 mm;

lowest lemmas 1.5-2 mm long, 0.7-1 mm wide, broadly elliptic, mostly glabrous but the keels and marginal veins appressed-pilose, obtuse, awned, awns 0.3-1.5 mm;

second florets 1-1.5 mm long and about equally wide, conspicuously inflated, spherical, with the distal portion of the margins inrolled, not or inconspicuously bilobed, lobes less than 1/5 as long as the lemmas, midveins sometimes excurrent to 1.5 mm.

1-2.5 mm;

upper glumes 1.9-3.5 mm;

lowest lemmas 1.5-2.8 mm long, 0.5-0.9 mm wide, elliptic, strongly laterally compressed, margins conspicuously hairy for most of their length, hairs 1-3 mm, strongly divergent, keels densely appressed pubescent, not or only minutely bilobed, apices awned, awns 1.4-4.8 mm;

second florets 1-1.6 mm, cylindrical to narrowly turbinate, shortly bilobed, lobes less than 1/5 as long as the lemmas, awned from the sinuses, awns 1.7-4 mm;

third florets often enclosed by the first sterile florets, 0.5-0.9 mm, turbinate or flabellate, as long as or longer than the subtending rachilla segments, sometimes inflated apically, unawned.

0.9-1.2 mm long, about 0.5 mm wide, obovoid.

about 1 mm long, about 0.5 mm wide.

= 40.

= 72.