Flora of North America species comparison

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

nodes terete, usually 1 exserted.

10-40 cm.

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.

intravaginal, innovations common, similar to the culms.

intravaginal.

mostly basal;

sheaths closed for 1/8 – 2/7 their length, terete, basal sheaths persistent, overlapping, bases usually not swollen;

ligules of innovations 1-2(3) mm, those of the upper cauline leaves to 4(5) mm, milky white, smooth, glabrous, obtuse;

blades of innovations widely spreading, persisting through the season, blades of cauline leaves 1-5(12) cm long, 2-4.5 mm wide, flat, moderately thick, soft, straight, smooth or the margins sparsely scabrous, apices broadly prow-shaped, blades of upper cauline leaves much reduced in length.

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.

2-6(8) cm, erect, ovoid to pyramidal, open or loosely contracted at maturity, fairly congested;

nodes with 1-2 branches, lowest internodes 0.6-1(1.5) cm;

branches 1-3(4) cm, ascending to spreading, straight, terete, usually smooth or sparsely scabrous, rarely moderately densely scabrous;

pedicels divaricate, shorter than the 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.

3.9-6.2 mm, ovate, lengths 1.5-2.5 times widths, laterally compressed, plump, sometimes bulbiferous;

florets 3-7, usually normal;

rachilla internodes 0.5-0.8 mm, smooth, glabrous or sparsely softly puberulent to short-villous.

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.

broadly lanceolate to narrowly ovate, keeled, keels sparsely scabrous;

lower glumes 3-veined;

upper glumes shorter than or subequal to the lowest lemmas;

calluses glabrous;

lemmas 3-5 mm, broadly lanceolate, keeled, keels and marginal veins short- to long-villous, lateral veins moderately prominent, intercostal regions sparsely to moderately short-villous, apices acute;

palea keels softly puberulent to short-villous over most of their length, apices scabrous;

anthers 1.3-2.3 mm.

= 28.

= 22, 23, 24,25, 26, 27, 28, 28+11, 30, 31, 32, 32+1, 33, 34, 35, 36, 37, 39, 40+1, 41, 42, ca. 43, 44, 46, ca. 48, 56.