Flora of North America species comparison

(5)10-30 cm tall, 1.2-1.5 mm thick, bases decumbent, terete or weakly compressed, hispidulous beneath the panicles;

nodes terete, 0(1) exserted.

30-120 cm, bases often decumbent.

closed for about 1/2 their length, terete, smooth or sparsely to moderately retrorsely scabrous near the collars, glabrous, bases of basal sheaths glabrous, distal sheath lengths 0.9-3.5 times blade lengths;

collars sparsely to moderately retrorsely scabrous, glabrous;

ligules 1-2 mm, scabrous, truncate to obtuse, ciliolate;

innovation blades to 30 cm long, adaxial surfaces moderately to densely scabrous or hispidulous on and between the veins;

cauline blades subequal in length, 1-2 mm wide, involute, moderately thick, moderately firm, arcuate, abaxial surfaces smooth or sparsely scabrous, adaxial surfaces moderately to densely scabrous or hispidulous on and between the veins, apices narrowly prow-shaped, flag leaf blades 1-9 cm.

closed for (1/20) 1/2-7/8 their length, terete, throats frequently ciliate near the point of fusion;

ligules 0.5-2.7 mm, smooth or sparsely scabrous, truncate to obtuse;

blades 0.7-5 mm wide, flat, thin, lax.

mainly intravaginal, some extravaginal.

mainly pseudointravaginal.

1.5-6 cm, erect, compact, ovoid, contracted, infrequently interrupted, congested, with 15-50 spikelets;

nodes with 1-2 branches, internodes densely hispidulous;

branches 0.5-2 cm, erect, stiff, terete to weakly angled, densely hispidulous, with 1-5 spikelets.

(6.7)9-20 cm, open, narrowly conical at maturity;

nodes with (2)3-10 branches per node;

branches (2)3-7 cm, spreading to eventually reflexed, straight, angled, angles several, densely scabrous, with 1-11 spikelets.

7-12 mm, lengths to 3 times widths, laterally compressed, not sexually dimorphic;

florets 3-6;

rachilla internodes usually shorter than 0.5 mm, smooth, glabrous.

2.5-4.4 mm, laterally compressed;

florets 2-3(4);

rachilla internodes longer than (1)1.2 mm, smooth, glabrous.

broadly lanceolate, 1/2 as long as to subequal to the adjacent lemmas, distinctly keeled;

lower glumes 3-veined;

upper glumes 4-4.5(7+) mm, 3-veined;

calluses usually with a crown of hairs, sometimes glabrous or diffusely webbed;

lemmas 5-7.5 mm, lanceolate, 5-veined, distinctly keeled, keels, marginal veins, and sometimes the lateral veins short- to long-villous or softly puberulent, rarely glabrous, lateral veins moderately prominent, intercostal regions smooth, glabrous, margins glabrous, apices acute;

palea keels scabrous to pectinate-ciliate, intercostal regions glabrous;

anthers vestigial (0.1-0.2 mm) or (2)2.5-3.5 (4) mm.

distinctly keeled, keels scabrous;

lower glumes 1(3)-veined;

upper glumes shorter than or subequal to the lowest lemmas;

calluses webbed;

lemmas 2.1-3.1 mm, broadly lanceolate, distinctly keeled, keels and marginal veins short-villous, extending to near the apices on the keels, lateral veins prominent, softly puberulent to short-villous, intercostal regions usually sparsely softly puberulent, smooth, apices obtuse to acute;

palea keels softly puberulent at midlength, apices finely scabrous;

anthers 1-1.8 mm.

= 28.

= 28.