Flora of North America species comparison

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

internodes sometimes pubescent below the nodes.

45-100 cm, forming corms, corms connected to the rhizomes by a rootlike, 10-30 mm structure, which usually remains attached to the corm;

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.

usually glabrous, often pilose at the throat and collar;

ligules 0.1-2 mm;

blades 2-5 mm wide, abaxial surfaces scabridulous over the veins, adaxial surfaces usually glabrous.

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.

5-26 cm;

branches 2-5 cm, usually appressed, sometimes divergent and flexuous, with 2-3 spikelets;

pedicels not sharply bent;

disarticulation above the glumes.

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

rachilla internodes 2.5-3 mm.

7-19 mm, with 3-7 bisexual florets, base of the distal florets concealed at anthesis;

rachilla internodes 1-2 mm, not swollen when fresh, not wrinkled when dry.

usually less than 1/2 the length of the spikelets;

lower glumes 3.5-6.4 mm long, 1.5-3 mm wide, 1-3-veined;

upper glumes 5-7 mm long, 2.3-3.5 mm wide, 5-7-veined;

lemmas 6-9 mm, glabrous, scabridulous, 5-11-veined, veins inconspicuous, apices rounded to acute, unawned;

paleas about 73 the length of the lemmas;

anthers 1.5-3 mm;

rudiments 1.5-3.5 mm, acute, distinct from the bisexual florets, sometimes surrounded by a small sterile floret similar in shape to the bisexual florets.

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.

= unknown.

= 18.