Flora of North America species comparison

30-80 cm, mostly erect, smooth below the panicles;

nodes slightly compressed, 2-5 exserted, top node at 1/2 - 3/4 the culm length.

20-110 cm.

closed for 1/10 – 1/5 their length, terete, bases of basal sheaths glabrous, distal sheath lengths 0.45-1 (1.1) times blade lengths;

ligules 0.2-0.8(1) mm, sparsely to densely scabrous, apices truncate, minutely ciliolate;

blades 0.8-3 mm wide, mostly flat, appressed, abruptly ascending to spreading, straight or somewhat lax, apices narrowly prow-shaped.

closed for (1/5)1/4 – 1/2(3/5) their length, distinctly compressed and keeled, usually densely retrorsely scabrous, rarely sparsely scabrous, margins not ciliate;

ligules 3-12 mm, densely scabrous, acute to acuminate;

blades (1.2)1.5-6(10) mm wide, flat, lax, apices broadly prow-shaped.

all or mostly extravaginal.

mixed intra- and extra-vaginal.

7-16(20) cm, lengths usually 2.5-4 times widths at maturity, usually erect, lax in shade forms, narrowly lanceoloid to ovoid, slightly to moderately congested;

nodes with 2-5 branches;

branches ascending to widely spreading, fairly straight, slender to moderately stout, angled, angles moderately to densely scabrous.

(6)12-40 cm, lax, eventually open, spikelets numerous, with 2-7 branches per node;

branches (3)5-18(23) cm, eventually spreading or drooping, angled, angles densely scabrous, with (5)8-40(120) spikelets.

3-8 mm, lengths 2.5-3.5 times widths, narrowly lanceolate to lanceolate, laterally compressed, usually not glaucous;

florets (1)2-5;

rachilla internodes usually shorter than 1 mm, smooth, muriculate, or scabrous, usually puberulent, infrequently hispidulous or glabrous.

(3)4-7(8) mm, laterally compressed, with 3-7 florets;

rachilla internodes shorter than 1 mm, smooth.

subulate to narrowly lanceolate, distinctly keeled, keels smooth or sparsely scabrous, apices sharply acute to acuminate;

lower glumes 3-veined, long-tapered to a slender point, lengths 6.4-11 times widths;

upper glumes shorter than or subequal to the lowest lemmas;

calluses webbed, hairs sparse, often short;

lemmas 2.4-4 mm, proximal lemma widths less than 1/5 times lengths, narrowly lanceolate to lanceolate, distinctly keeled, keels and marginal veins short-villous, lateral veins glabrous, obscure, intercostal regions smooth or muriculate, glabrous, margins glabrous, apices acute, usually partially bronze-colored;

palea keels scabrous, intercostal regions glabrous;

anthers 0.8-1.9 mm.

distinctly keeled, keels scabrous;

lower glumes 2-3.5 mm, 1-veined;

upper glumes 2.5-4.2 mm, shorter than or subequal to the lowest lemmas;

calluses webbed;

lemmas 2.6-4.2 mm, narrowly lanceolate, distinctly keeled, scabrous distally, keels and marginal veins short- to long-villous, keel hairs extending to midlength, marginal vein hairs to 1/3 the lemma length, lateral veins and intercostal regions usually sparsely softly puberulent, lateral veins prominent, apices narrowly acute;

palea keels scabrous, glabrous;

anthers 0.3-1 mm.

= 28, 35, 42, 48, 50, 56.

= 14, 28.