Flora of North America species comparison

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

internodes scabridulous above the nodes.

55-100 cm, not forming corms;

internodes smooth, basal internodes not thickened.

usually scabridulous, sometimes sparsely pilose;

ligules 2-6 mm;

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

often scabrous on the keels, otherwise smooth;

ligules 1-7 mm;

blades 2-5 mm wide, both surfaces glabrous, scabridulous.

7-30 cm;

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

pedicels straight;

disarticulation above the glumes.

13-25 cm;

branches 1-9 cm, straight and appressed or flexible and ascending to strongly divergent, with 1-12 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.

8-16 mm long, 1.5-5 mm wide, parallel-sided when mature, with 2-5 bisexual florets;

rachilla internodes 1.9-2.1 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.

green, pale, or purplish-tinged;

lower glumes 3.5-6 mm long, 2-3 mm wide, 3-5-veined;

upper glumes 5-8 mm long, 2-3 mm wide, 5-veined;

lemmas 6-10 mm, glabrous, chartaceous on the distal 1/3, 5-11-veined, veins conspicuous, apices rounded to acute, unawned;

paleas about 2/3 the length of the lemmas;

anthers 1-2.5 mm;

rudiments 1.8-5 mm, acute to acuminate, resembling the bisexual florets.

=18.

= 18.