Flora of North America species comparison

10-60 cm.

26-50 cm tall, 0.5-0.9 mm thick, bases decumbent or nearly erect, frequently branching above the base, terete or weakly compressed;

nodes terete, 1-2 exserted.

closed for 1/3 – 2/3 their length, terete, smooth;

ligules 1.5-3.5 mm, smooth or sparsely scabrous;

blades 1.5-4 mm wide, flat, thin, soft, apices broadly prow-shaped.

closed for 2/5 – 7/10 their length, weakly keeled, sparsely scabrous, glabrous, bases of basal sheaths glabrous, distal sheath lengths 0.6-2.4 times blade lengths;

collars scabrous or pubescent on the margins;

ligules (1)2-3 mm, moderately densely scabrous, truncate, obtuse, or acute, lacerate to entire;

innovation blades to 20 cm, adaxial surfaces sparsely scabrous, glabrous or hispidulous on and between the veins;

cauline blades 1.5-2.4 mm wide, folded or flat, thin, soft, abaxial surfaces smooth, veins prominent, keel and margins scabrous, adaxial surfaces moderately scabrous over the veins, sparsely scabrous between the veins, apices narrowly prow-shaped, flag leaf blades 2.9-8.6(11) cm.

mixed intra- and extravaginal.

extra-, pseudo-, and intravaginal.

4-15 cm, nodding, open, with numerous spikelets and 1-2 branches per node;

branches (2)3-7 cm, spreading to reflexed, lower branches usually reflexed, flexuous, usually terete, smooth or sparsely scabrous, with (3)6-18 spikelets.

(4)5.5-10.5(12.5) cm, erect, ovoid to broadly pyramidal, open, or eventually loosely contracted, sparse, with 10-40 spikelets;

nodes with 1-2 branches;

branches 2.1-4.5(7) cm, ascending, lax, angled, angles moderately to densely scabrous, less scabrous between the angles, with 1-9 spikelets.

4-6 mm, lanceolate to broadly lanceolate, usually partly to wholly purplish, with 3-5 florets;

rachilla internodes shorter than 1 mm, smooth.

5.3-9 mm, lengths to 3 times widths, laterally compressed, not sexually dimorphic;

florets (2)3-6(7);

rachilla internodes 1-1.3 mm, visible from the sides, usually sparsely to densely, coarsely scabrous, infrequently smooth.

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

lower glumes 1-veined;

upper glumes shorter than or subequal to the lowest lemmas;

calluses webbed;

lemmas 2-3.5 mm, lanceolate, partly purple to fairly strongly purple, distinctly keeled, keels and marginal veins short- to long-villous, keels hairy for 2h-ls their length, lateral veins usually sparsely softly puberulent at least on 1 side, lateral veins obscure to moderately prominent, intercostal regions smooth, minutely bumpy, glabrous, apices acute, slightly bronze-colored or not;

palea keels scabrous, usually softly puberulent at midlength;

anthers 0.6-1 mm.

distinctly keeled;

lower glumes (2)2.7-3.8 mm, 3-veined, upper glumes (2.3)2.9-3.9 mm;

calluses diffusely webbed, hairs 1/3-1/2 the lemma length;

lemmas (3.2)4.25-5 mm, lanceolate to narrowly lanceolate, distinctly keeled, glabrous, moderately to densely, infrequently sparsely, scabrous, lateral veins prominent, margins narrowly scarious, glabrous, apices acute to narrowly acute;

paleas 3/4 as long as to subequal to the lemmas, keels scabrous, intercostal regions scabrous;

anthers (1.4)1.75-2.6 mm, or vestigial (0.1-0.2 mm).

= 28.

= unknown.