Flora of North America species comparison

1-12 cm, slender.

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.

closed for 1/6 – 1/4 their length, terete;

ligules 1-3 mm, milky white to hyaline, smooth;

blades 0.5-2 mm wide, flat or folded, or slightly inrolled, thin, without papillae (at 100x), apices narrowly prow-shaped.

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.

all or mainly intra-vaginal.

extravaginal or mixed extra- and intravaginal.

1-3 cm, erect, contracted, usually exserted from the sheaths;

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

pedicels shorter than the spikelets.

(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.

3-4 mm, laterally compressed, green or anthocyanic;

florets 2-3;

rachilla internodes shorter than 1 mm, smooth.

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.

usually equaling or exceeding the lowest lemmas, sometimes also equaling or exceeding the upper florets, lanceolate to broadly lanceolate, distinctly keeled, keels smooth;

lower glumes 3-veined;

calluses glabrous;

lemmas 2.5-3 mm, lanceolate, distinctly keeled, thin, usually glabrous, keels and marginal veins rarely sparsely puberulent proximally, apices acute;

palea keels scabrous;

anthers 0.2-0.8 mm.

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.

= 14.

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