Flora of North America species comparison

29-100 cm, forming corms, corms almost sessile on the connecting rhizomes;

internodes scabridulous above the nodes.

45-100 cm, not forming corms;

internodes sometimes scabridulous above the nodes.

usually scabridulous, sometimes sparsely pilose;

ligules 2-6 mm;

blades 1.5-5 mm wide, abaxial surfaces scabridulous, adaxial surfaces with hairs.

glabrous or pilose;

ligules 0.5-1.5 mm;

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

7-30 cm;

branches 2-6.5 cm, appressed, usually straight, with 1-5 spikelets;

pedicels straight;

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.

6-24 mm, with 4-7 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.

from (1/2)2/3 as long as to equaling the spikelets;

lower glumes 5.5-10.5 mm long, 2-3 mm wide, 3-5-veined;

upper glumes 6-14 mm long, 2.3-3.5 mm wide, 5-7-veined;

lemmas 6-12 mm, glabrous, smooth or scabrous, 7-11-veined, veins prominent, apices emarginate to acute, unawned;

paleas about 3/4 the length of the lemmas;

anthers 3, 1.5-4 mm;

rudiments 1.5-5 mm, truncate to tapering, sometimes resembling the bisexual florets in shape.

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.