Flora of North America species comparison

60-160 cm, thickened basally, sometimes appearing cormous;

internodes sometimes pubescent below the nodes.

60-200 cm, not forming corms, often branched from the lower nodes;

internodes smooth.

usually glabrous, sometimes pilose or retrorsely scabrous, particularly at the throat, veins often prominent;

ligules 2-4 mm;

blades 15-25 cm long, 5-12 mm wide, both surfaces usually scabridulous, glabrous, sometimes the adaxial surfaces with hairs.

glabrous, sometimes scabridulous, sometimes purplish;

ligules 2.5-9 mm;

blades 2-5 mm wide, abaxial sufaces scabridulous, adaxial surfaces puberulent.

12-30 cm;

branches 7-11 cm, spreading to reflexed, with 4-7 spikelets, spikelets restricted to the distal portion, axils frequently with brownish pulvini;

pedicels straight;

disarticulation above the glumes.

12-40 cm;

branches 3.5-9 cm, appressed, with 5-15 spikelets;

pedicels straight;

disarticulation above the glumes.

12-18 mm, with 3-5 bisexual florets;

rachilla internodes 2.5-3 mm.

9-18 mm, with 3-5 bisexual florets;

rachilla internodes 1-1.3 mm, not swollen when fresh, not wrinkled when dry.

4.5-7 mm long, 1-1.5 mm wide, 1-3-veined;

upper glumes 6.5-9 mm long, 1.2-1.8 mm wide, 3-5-veined;

lemmas 9.5-12 mm, glabrous or scabrous, 7-veined, apices bifid to emarginate, awned, awns 3-10 mm;

paleas about 2/3 the length of the lemmas;

anthers 1.3-2.5 mm;

rudiments 3.5-6 mm, tapering, resembling the bisexual florets.

7-12 mm long, 2-3 mm wide, 5-7-veined;

upper glumes 8-15 mm long, 2.5-3.5 mm wide, 5-7-veined;

lemmas 8-11 mm, glabrous, chartaceous for the distal 1/3 or more, 7-9-veined, sometimes purplish basally, veins inconspicuous, apices rounded to acute, unawned;

paleas about 3/4 the length of the lemmas;

anthers 3, 1-2 mm;

rudiments 2-6 mm, blunt, enclosed in empty lemmas resembling those of the bisexual florets.

= unknown.

= 18.