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.

10-33(45) cm, usually decumbent, terete;

nodes terete, 0(1) exserted.

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 1/7 – 1/5(1/3) their length, terete, usually lustrous, bases of basal sheaths glabrous;

ligules (1.5)2-7 mm, smooth or sparsely scabrous, margins usually decurrent, apices obtuse to acuminate;

innovation blades similar in texture and shape to those of the culms;

cauline blades 2-9 cm, gradually increasing or decreasing in length upwards, 1.5-3 mm wide, folded to involute, moderately thick, soft, abaxial surfaces smooth, adaxial surfaces smooth or somewhat scabrous, usually glabrous, infrequently sparsely hispidulous, apices narrowly prow-shaped.

all or mostly extravaginal.

extra- and intravaginal.

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.

2.5-6(12) cm, erect, narrowly lanceolate, contracted or narrowly ovate in some bulbiferous plants, moderately congested, with 7-40 spikelets;

nodes with (1)2(4) branches;

branches 1-3 cm, erect to ascending, straight, sulcate, smooth or sparsely to moderately scabrous, with 1-10 spikelets in the distal 1/3 – 2/3.

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.

4.8-7.4 mm, lengths 3.5-4 times widths, lanceolate, weakly laterally compressed, sometimes bulbiferous, lustrous;

florets (2)3-5(6), normal or bulb-forming;

rachilla internodes 0.8-2 mm, smooth, sometimes sparsely hispidulous.

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.

mostly broadly scarious, somewhat lustrous, keels indistinct, smooth or sparsely scabrous distally;

lower glumes 3-veined;

upper glumes frequently exceeding the lowest lemmas;

calluses glabrous or with a crown of hairs, hairs to 2 mm;

lemmas (3.3)3.5-7 mm, lanceolate, usually weakly keeled, more or less evenly and somewhat loosely to densely hairy over the proximal 1/3-1/2, hairs usually longer than 0.5 mm, sparsely scabrous in the middle 1/3, smooth distally, lateral veins obscure, margins weakly inrolled, broadly scarious, glabrous, apices long-scarious, acute to shortly obtuse, often erose, often bronze-colored below the apices;

palea keels sparsely scabrous, softly puberulent at midlength, intercostal regions softly puberulent;

anthers usually all aborted late in development and 0.8-1.8 mm, infrequently well developed and 2-2.8 mm.

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

= 63, 70.