Flora of North America species comparison

15-100 cm, slender to middling.

2-15 cm, prostrate to erect, slender;

nodes terete, usually 1 exserted.

closed for 1/4 - 3/5 their length, terete, smooth or sparsely scabrous, margins not ciliate;

ligules 1.5-4(6) mm, smooth to sparsely scabrous, obtuse to acute;

blades 1-4 mm wide, flat, thin, lax, soft, apices narrowly prow-shaped.

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.

mostly extravaginal.

intravaginal, sterile shoots common, similar to the culms.

5-15 cm, lax, open, sparse;

nodes with 1-3(5) branches;

branches (2)3-8 cm, spreading to reflexed, capillary, usually angled, infrequently only sulcate or subterete, angles usually moderately densely scabrous, sometimes only sparsely so, with (3)4-15 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.

4-8 mm, lanceolate or narrowly lanceolate, green or partly purple to dark purple;

florets 2-5;

rachilla internodes 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.

subulate to lanceolate, thin, distinctly keeled, keels usually scabrous;

lower glumes subulate to narrowly lanceolate, 1-veined;

upper glumes distinctly shorter than to nearly equaling the lowest lemmas;

calluses sparsely webbed;

lemmas 3-4 mm, lanceolate, often partly purple, distinctly keeled, thin, smooth, or with sparse hooks apically, keels and marginal veins softly puberulent to long-villous, hairs extending 1/4 - 2/3 the keel length, sometimes sparse, lateral veins and intercostal regions glabrous, margins glabrous, infolded, apices sharply acute to acuminate, usually bronze-colored;

palea keels nearly smooth, scabrous, or pectinately ciliate;

anthers 0.2-1.1 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.

= 42.

= 14.