Flora of North America species comparison

to 300 cm, erect.

10-100+ cm.

glabrous or scabrous, often ciliate apically;

ligules ciliate;

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

usually glabrous;

ligules to 4 mm, erose or ciliate;

blades to 30 cm long, to 15 mm wide, basal hairs to 4 mm, otherwise usually glabrous, occasionally pilose.

digitate, with 9-30 evidently distinct branches;

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

digitate, with 4-20, evidently distinct branches;

branches 5-10 cm, erect to ascending, averaging 10 spikelets per cm.

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

strongly imbricate, with 1 bisexual and 1(2) sterile floret(s).

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.

1.5-2.5 mm;

upper glumes 2.5-4.3 mm;

lowest lemmas 2.5-4.2 mm, keels usually prominently gibbous, glabrous, or conspicuously pilose, sides not grooved, margins glabrous, scabrous or pilose basally, with conspicuously longer hairs distally, hairs longer than 1.5 mm, lemma apices not conspicuously bilobed, awned, awns 2.5-15 mm;

second florets 1.4-2.9 mm long, 0.4-0.8 mm wide, somewhat widened distally, not inflated, bilobed, lobes less than 1/5 as long as the lemmas, awned from the sinuses, awns 3-9.5 mm;

third florets greatly reduced, unawned and shorter than the subtending rachilla segment or absent but the rachilla segment present.

1-1.5 mm long, about 0.5 mm wide.

1.5-2 mm long, about 0.5 mm wide, elliptic.

= 20, 30, 40.

= 20, 26, 30, 40.