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.

20-95 cm tall, 0.8-1.5 mm thick.

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 1/3-2/3 their length;

ligules 0.2-3(4) mm, smooth or sparsely scabrous, truncate to obtuse;

blades 1-3.6 (6) mm wide, flat, thin, lax, veins prominent.

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.

4-20(24) cm long, less than 1/4 the plant height, lax;

nodes with 1-3 branches;

branches ascending to spreading, lax, angled, angles prominent, scabrous.

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.

3-5.6 mm, laterally compressed;

florets 2-5;

rachilla internodes glabrous, usually shorter than 1 mm.

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.

2/3 – 3/4 as long as the adjacent lemmas, distinctly keeled;

lower glumes 1(3)-veined;

upper glumes shorter than or subequal to the lowest lemmas;

calluses webbed;

lemmas 2.4-4 mm, lanceolate to broadly lanceolate, distinctly keeled, usually glabrous, bases of marginal veins rarely sparsely softly puberulent, lateral veins prominent, intercostal regions smooth, minutely bumpy, apices obtuse to sharply acute or acuminate;

palea keels scabrous;

anthers 0.4-1.5 mm.

= 28.