Flora of North America species comparison

25-120 cm, erect or the bases decumbent, sometimes branching above the base, terete or weakly compressed, scabrous below the panicle;

nodes terete or slightly compressed, proximal nodes often slightly swollen, uppermost node at or above (73)72 the culm length.

10-30 cm.

closed for 1/10 – 1/5 their length, slightly compressed, glabrous or sparsely retrorsely scabrous, bases of basal sheaths glabrous, distal sheath lengths 0.7-2.2 times blade lengths;

ligules (1)1.5-6 mm, smooth or sparsely to moderately scabrous, apices obtuse to acute, frequently lacerate, usually minutely ciliolate;

blades 1.5-8 mm wide, flat, usually several per culm, steeply ascending or spreading to 80°, often lax distally, apices narrowly prow-shaped.

closed for 1/4 - 3/5 their length, terete;

ligules 1-2 mm, smooth or sparsely scabrous, truncate to obtuse;

blades 1-3 mm wide, flat, thin, soft, apices broadly prow-shaped.

extravaginal or mixed extra- and intravaginal.

mainly extravaginal.

(9)13-30(41) cm, lengths 73-72 times widths at maturity, lax, eventually open, sparsely to moderately congested, with 25-100+ spikelets;

nodes with 2-9 branches;

branches 4-15 cm, 3/10 – 1/2 the panicle length, initially erect, eventually widely spreading to slightly reflexed, fairly straight, slender, angles densely scabrous.

2.5-10 cm, lax to nearly erect, open, sparse, with 1-2 branches per node;

branches (2)3-6 cm, ascending to spreading, lower branches infrequently reflexed, lax or drooping, capillary, terete to slightly sulcate, usually smooth, rarely some branches within a panicle sparsely scabrous, with 1-3(5) spikelets.

3-5 mm, lengths 3-3.5 times widths, narrowly to broadly lanceolate, laterally compressed;

florets (1)2-5;

rachilla internodes mostly shorter than 1 mm, usually muriculate, sometimes smooth, rarely sparsely hispidulous.

4-6 mm, laterally compressed, broadly lanceolate to ovate, usually dark purple, with 3-5 florets;

rachilla internodes smooth, glabrous.

subulate to lanceolate, distinctly keeled, keels smooth or sparsely scabrous;

lower glumes with lengths 6.4-10 times widths, 3-veined, long-tapered to a slender point;

calluses sparsely to moderately densely webbed, hairs (1/2)2/3 the lemma length;

lemmas 2-3 mm, narrowly lanceolate to lanceolate, distinctly keeled, keels straight or gradually arched, usually abruptly inwardly arched at the junction of the scarious apices, keels and marginal veins short-villous, lateral veins obscure, intercostal regions muriculate, glabrous, margins distinctly inrolled, glabrous, apices obtuse or acute, usually partially bronze-colored, frequently incurved and blunt with a short, hyaline margin;

palea keels scabrous, intercostal regions glabrous;

anthers 1.3-1.8 mm.

lanceolate to broadly lanceolate, thin, distinctly keeled, keels smooth or nearly so;

lower glumes 1-veined;

upper glumes shorter than or subequal to the lowest lemmas;

calluses sparsely webbed;

lemmas 3-4 mm, broadly lanceolate, usually strongly purple, distinctly keeled, thin, keels and marginal veins short- to long-villous, keels hairy for 1/2-1/3 their length, lateral veins glabrous, intercostal regions smooth, glabrous, margins glabrous, not infolded, apices acute, sometimes slightly bronze-colored;

palea keels sparsely scabrous at midlength;

anthers 0.4-1 mm.

= 28, 30, 32, 35, 42, 56, 84.

= 28, 42.