Flora of North America species comparison

10-100+ cm.

30-45 cm.

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.

glabrous or sparsely pilose;

ligules membranous, not or only shortly ciliate;

blades to 15 cm long, about 4 mm wide, scabrous.

digitate, with 4-20, evidently distinct branches;

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

with 8-10 clearly separate branches, these usually digitate, occasionally a poorly-developed second whorl present just below the terminal whorl;

branches to 20 cm, divergent, basal 2-5 cm without spikelets, averaging 3-4 spikelets per cm elsewhere.

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

with 1 bisexual and 1 sterile floret.

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.

2.7-3 mm;

upper glumes 3.5-3.8 mm;

lowest lemmas 3.7-4.3 mm long, 0.7-0.8 mm wide, lanceolate to narrowly ovate, sides not conspicuously grooved, margins glabrous or sparsely appressed pubescent distally with hairs shorter than 1 mm, apices acute, awned, awns 7-11 mm;

second florets 2-2.5 mm long, about 0.5 mm wide, narrowly elliptic, acute, inconspicuously bilobed, awns 4.5-6.5 mm.

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

about 2.3 mm long, about 0.5 mm wide, ellipsoid, trigonous.

= 20, 26, 30, 40.

= unknown.