Flora of North America species comparison

5-40(80) cm, erect to spreading, straight, wiry, bases straight or slightly decumbent;

nodes terete or slightly compressed, usually 0-1 exserted, top node at 1/10-1/3 the culm length.

5-15(20) cm, slender, leafless above the basal tuft.

closed for 1/10 – 1/5 their length, terete, bases of basal sheaths glabrous or sparsely minutely hairy, hairs 0.1-0.2 mm, distal sheath lengths 1.1-4 times blade lengths;

ligules 1-4(5) mm, sparsely to densely scabrous, apices obtuse to acute, minutely ciliolate;

blades 0.8-2.5 mm wide, flat or folded, thin, soft, appressed or abruptly ascending to spreading, straight, apices narrowly prow-shaped.

closed for 1/10 – 1/4 their length, terete;

ligules 0.4-5.5 mm, milky white to hyaline, smooth or scabrous, apices truncate to acute;

blades 0.8-1.5(2) mm wide, involute, moderately thick, soft, apices narrowly prow-shaped.

all or mostly extravaginal.

all or mainly intravaginal.

1-10(20) cm, lengths 3-5 times widths at maturity, rarely racemelike with branches of irregular length, erect, narrowly lanceoloid to ovoid, contracted to somewhat open, sparse, proximal internodes shorter than 1.5(4) cm;

nodes with 2-3(5) branches;

branches erect, ascending or weakly spreading, fairly straight, short, stout, angled, angles moderately to densely scabrous, rarely only scabrous distally, glaucous;

pedicels usually shorter than the spikelets.

1.5-5 cm, erect, lanceoloid to ovoid, contracted, congested;

nodes with 1-3 branches;

branches to 1.5 cm, erect, slender, terete, sulcate or angled, smooth or the angles sparsely scabrous;

pedicels usually shorter than the spikelets.

3-7(9) mm, lengths 2-3 times widths, laterally compressed, rarely bulbiferous, usually glaucous;

florets 2-5, rarely bulb-forming;

rachilla internodes to 1.2 mm, smooth, muriculate, or scabrous, glabrous or sparsely to densely hispidulous or puberulent.

4-6.5 mm, laterally compressed, rarely bulbiferous, frequently strongly anthocyanic;

florets 2-5, rarely bulb-forming;

rachilla internodes usually shorter than 1 mm, smooth or scabrous.

subequal, narrowly to broadly lanceolate, distinctly keeled, keels smooth or sparsely scabrous, apices acute;

lower glumes 3-veined;

upper glumes 2-3.8(5.2) mm, lengths usually more than 4.1 times widths, distinctly shorter to subequal to the lowest lemmas;

calluses glabrous or webbed, webs from minute to more than 1/2 the lemma length;

lemmas 2.5-4 mm, lanceolate to broadly lanceolate, distinctly keeled, keels and marginal veins short-villous, lateral veins obscure, usually sparsely softly puberulent to short-villous, intercostal regions smooth, sometimes weakly muriculate, glabrous or puberulent, margins glabrous, apices usually partially bronze-colored, obtuse or acute;

palea keels scabrous, glabrous or softly puberulent at midlength, intercostal regions glabrous or softly puberulent;

anthers (1)1.2-2.5 mm, mature sacs 0.2 mm wide, rarely aborted late in development.

subequal to slightly longer than the adjacent lemmas, lanceolate to broadly lanceolate, distinctly keeled, keels smooth;

lower glumes (1)3-veined, lateral veins often faint and short;

upper glumes exceeding or exceeded by the upper florets;

calluses glabrous or webbed;

lemmas 3-4.6 mm, lanceolate to broadly lanceolate, distinctly keeled, thin, keels and marginal veins usually short- to long-villous, hairs extending along 3/4 - 5/6 of the keel, infrequently glabrous, intercostal regions glabrous or softly puberulent to short-villous, apices acute;

palea keels scabrous, often short-villous to softly puberulent at midlength, sometimes glabrous;

anthers 0.2-1.2(1.8) mm.

= 34, 42, 44, 47, 48, 49, 50, 56, 56, 57, 58, 60, 63, 64, 65, 70, 75, 78, ca. 100.

= 42.