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.

2-15 cm, prostrate to erect, slender;

nodes terete, usually 1 exserted.

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 about 1/3 their length, terete or weakly compressed, smooth;

ligules 0.5-3 mm, smooth, glabrous, decurrent, obtuse to truncate;

blades 1-3(4) mm wide, flat, thin, soft, smooth, margins usually slightly scabrous, apices broadly prow-shaped.

mainly intravaginal, some extravaginal.

intravaginal, sterile shoots common, similar to the culms.

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.

1-6 cm, lengths 1.5-3 times widths, erect;

nodes with 1-2(5) branches;

branches ascending, straight, terete, smooth, with crowded 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.

3-5 mm, laterally compressed;

florets 2-6;

rachilla internodes smooth, glabrous, usually exposed in side view, distal internodes 1/2 - 3/4 the length of tbe distal lemma.

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.

smooth, distinctly keeled, keels smooth;

lower glumes 1-veined;

upper glumes shorter than or subequal to the lowest lemmas;

calluses glabrous;

lemmas 2-2.5 mm, lanceolate, distinctly keeled, smooth throughout, the keels, marginal and lateral veins crisply puberulent to long-villous, lateral veins prominent, intercostal regions glabrous, margins smooth, glabrous, apices obtuse to acute;

palea keels smooth, short- to long-villous;

anthers 0.1-0.6 mm, more or less spherical to short-elliptical prior to dehiscence, those of the upper 1-2 florets commonly vestigial.

= 28.

= 14.