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.

55-100 cm, not forming corms;

internodes smooth, basal internodes not thickened.

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.

often scabrous on the keels, otherwise smooth;

ligules 1-7 mm;

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

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.

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.

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.

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.

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.

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.