Flora of North America species comparison

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

internodes scabridulous above the nodes.

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

internodes smooth.

usually scabridulous, sometimes sparsely pilose;

ligules 2-6 mm;

blades 1.5-5 mm wide, abaxial surfaces scabridulous, 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.

7-30 cm;

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

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.

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.

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

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

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.

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.

=18.

= 18.