Flora of North America species comparison

to 300 cm, erect.

15-60 cm, erect.

glabrous or scabrous, often ciliate apically;

ligules ciliate;

blades to 30 cm long, 15 mm wide, scabrous.

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.

digitate, with 9-30 evidently distinct branches;

branches 8-20 cm, usually somewhat divaricate, spikelet-bearing to the base, averaging 10 spikelets per cm.

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

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

disarticulation beneath the glumes.

strongly imbricate, tawny, with 1 bisexual and (1)2-4 usually staminate, sometimes sterile florets.

with 1 bisexual and 1 sterile floret.

1.4-2.8 mm;

upper glumes 2.2-3.5 mm;

lowest lemmas 2.5-4.2 mm long, 0.7-1 mm wide, ovate to obovate or elliptic, somewhat gibbous, sides not grooved, pubescence variable, sides usually glabrous, sometimes scabrous or appressed pubescent, margins usually glabrous or appressed pubescent on the lower portions, sometimes throughout their length, sometimes with strongly divergent hairs distally, occasionally with strongly divergent hairs their entire length, divergent hairs, when present, 1+ mm, lemma apices inconspicuously bilobed, awned, awns 1.5-6.5 mm;

second florets staminate or sterile, 2.2-3.2 mm long, 0.3-1 mm wide, similar to the first floret but more cylindrical, not widened distally, inflated, if at all, only near the apices, inconspicuously bilobed, awned, awns 0.8-3.2 mm;

distal florets progressively smaller, longer than the subtending rachilla segment, awn-tipped or unawned.

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.

1-1.5 mm long, about 0.5 mm wide.

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

= 20, 30, 40.

= 40.