Flora of North America species comparison

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.

45-100 cm, not forming corms;

internodes sometimes scabridulous above the nodes.

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.

glabrous or pilose;

ligules 0.5-1.5 mm;

blades 1.8-6 mm wide, abaxial surfaces glabrous, scabridulous, adaxial surfaces with hairs.

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.

4-25 cm;

branches 3.5-6 cm, appressed to spreading, straight, with 2-5 spikelets;

pedicels sharply bent below the spikelets;

disarticulation below the glumes.

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.

6-11 mm, with (1)2(4) bisexual florets, floret apices at about the same level;

rachilla internodes 1.5-1.7 mm.

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.

4.5-8 mm long, 3-4 mm wide, 5-7-veined;

upper glumes 5-9 mm long, 2.5-3.5 mm wide, 5-6-veined;

lemmas 6-11 mm, glabrous or scabrous, indurate, 9-11-veined, veins prominent, apices rounded to acute, unawned;

paleas about 3/4 the length of the lemmas;

anthers 1-3 mm;

rudiments 2-3 mm, clublike, not resembling the bisexual florets, at a sharp angle to the rachilla.

= 18.

= 18.