Flora of North America species comparison

to 300 cm, erect.

30-50 cm.

glabrous or scabrous, often ciliate apically;

ligules ciliate;

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

glabrous;

ligules short-ciliate;

blades 9-17 cm long, 0.2-0.3 mm wide, without basal hairs, glabrous, sometimes scabrous.

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 5-13 clearly distinct branches;

branches 5-23 cm, spikelet-bearing to the base or within 1 cm of the base, averaging 6 spikelets per cm elsewhere.

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

dark brown to black, with 1 bisexual and 1(2) staminate 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.

1.4-2.3 mm;

upper glumes 2.8-4.2 mm;

lowest lemmas 1.8-4.5 mm long, 0.2-0.7 mm wide, narrowly elliptic, becoming very dark, often almost black at maturity, sides not grooved, mostly glabrous but the margins appressed pubescent, sometimes sparsely so, hairs shorter than 1 mm, apices truncate, awned, awns 3.1-16 mm;

second florets 1.3-3.5 mm long, 0.5-0.9 mm wide, not inflated, truncate, not or only minutely bilobed, awned, awns 3.1-12.5 mm;

anthers about 0.6 mm.

1-1.5 mm long, about 0.5 mm wide.

1.7-2.2 mm long, 0.3-0.5 mm wide, ellipsoid to narrowly obovate, trigonous.

= 20, 30, 40.

= 40.