Flora of North America species comparison

2-20(45) cm, prostrate to erect, slender;

nodes terete, usually 1 exserted.

5-35 cm tall, 0.5-0.7 mm thick, erect or the bases decumbent, with 0-1 exserted nodes.

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

ligules 0.5-3(5) mm, smooth, glabrous, decurrent, obtuse to truncate;

blades 1-10 cm long, 1-3(6) mm wide, flat or weakly folded, thin, soft, smooth, margins usually slightly scabrous, apices broadly prow-shaped.

closed for 2/5 – 4/5 their length, terete, smooth and glabrous, bases of basal sheaths glabrous;

collars smooth, glabrous;

ligules (1)2-4 mm, colorless, transparent, smooth, margins decurrent or not, apices truncate to acute, ligules of innovation and cauline leaves alike;

innovation blades smooth or sparsely scabrous abaxially;

cauline blades 0.5-1 mm wide, flat, folded, or involute, thin, lax, filiform, usually soon withering, both surfaces smooth or sparsely scabrous, apices narrowly prow-shaped.

intravaginal, innovations common, similar to the culms.

intravaginal.

1-7(10) cm, lengths 1.2-1.6 times widths, erect;

nodes with 1-2(3) branches;

branches ascending to spreading or reflexed, straight, terete, smooth, with crowded or loosely arranged spikelets.

1-5(8) cm, erect to lax, lanceoloid to ovoid or pyramidal, contracted to open, sparse, with (1)6-17(22) spikelets;

nodes with 1-2 branches;

branches 1-4 cm, erect to spreading, slender, terete, smooth or sparsely to rarely moderately densely scabrous, with 1-2(3) spikelets.

3-5 mm, laterally compressed;

florets 2-6;

rachilla internodes smooth, glabrous, concealed or exposed, distal internodes less than 1/2(3/4) the length of the distal lemma.

4-8 mm, lengths to 3 times widths, broadly lanceolate to broadly ovate, laterally compressed, not sexually dimorphic;

florets 2-8;

rachilla internodes glabrous.

smooth, distinctly keeled, keels smooth;

lower glumes 1-veined;

upper glumes shorter than or subequal to the lowest lemma;

calluses glabrous;

lemmas 2.5-4 mm, lanceolate, distinctly keeled, smooth throughout, the keels, marginal veins, and, usually, lateral veins crisply puberulent to long-villous, rarely glabrous throughout, lateral veins prominent, intercostal regions glabrous, margins smooth, glabrous, apices obtuse to acute;

palea keels smooth, usually short- to long-villous, rarely glabrous;

anthers 0.6-1.1 mm, oblong prior to dehiscence, those of the upper 1-2 florets usually vestigial.

thin, somewhat lustrous, distinctly keeled;

lower glumes 3-veined, distinctly shorter than the lowest lemmas;

calluses glabrous;

lemmas 3.5-7 mm, lanceolate, distinctly keeled, thinly membranous, smooth or scabrous, glabrous, lateral veins moderately prominent to prominent, margins glabrous, apices acute to truncate and erose;

palea keels smooth or scabrous, glabrous or pectinately ciliate;

anthers vestigial (0.1-0.2 mm) or 1.3-3 mm.

= 28.

= unknown.