Flora of North America species comparison

15-130 cm, slender to stout, not woody, erect to decumbent, straight to zigzag, simple to profusely branched;

nodes sparsely to densely pilose.

slender, wiry, glabrous, often with minute purple streaks and dots, ascending from a decumbent base, often branching extensively at the base and rooting at the lower nodes.

rounded, hirsute or hispid, hairs papillose-based;

ligules membranous, ciliate, cilia 0.5-1.5 mm;

blades 5-40 cm long, 3-18 mm wide, linear, spreading.

usually shorter than the internodes, glabrous, margins short-ciliate;

ligules usually less than 0.3 mm, membranous, erose, ciliate;

blades 4-15 cm long (rarely longer), 2-3 mm wide, flat or slightly involute, glabrous on both surfaces, margins scabridulous, especially towards the apices, bases narrowed.

13-50 cm long, 7-24 cm wide, usually more than 1/2 as long as the plants, included at the base or exserted at maturity, disarticulating at the base of the peduncles at maturity and becoming a tumbleweed;

branches spreading;

pedicels 0.5-2.8 mm, scabrous, pilose.

4-17 cm, 1/2 to nearly as wide as long;

branches few, capillary, ascending or spreading, scabridulous, with a few spikelets distally;

pedicels 0.5-10 mm.

1.9-4 mm, ellipsoid to lanceoloid, often red-purple, glabrous.

3.2-4 mm long, about 1.5 mm wide, broadly ellipsoid or obovoid, tuberculate, hispid, faintly veined, acute or acuminate at the apices.

usually less than 1 mm, obtuse or acute;

upper glumes and lower lemmas subequal, distinctly tuberculate, hispid, with stiff hairs arising from wartlike bases;

upper florets 2.7-3.2 mm long, 1.3-1.6 mm wide, obovoid or ellipsoid, nearly smooth, minutely papillose, or cross-rugulose, subacute to acute.

florets sterile;

lower glumes 1/3– 1/2 as long as the spikelets, 1-3-veined;

upper glumes 1.8-3.1 mm, 7-9-veined, midveins scabridulous;

lower lemmas 1.9-3 mm, extending 0.4-1.1 mm beyond the upper florets, often stiff, straight, prominently veined distally;

upper florets stramineous or nigrescent, sometimes with a prominent lunate scar at the base, often disarticulating before the glumes, leaving the empty glumes and lower lemmas temporarily persisting on the panicles.

= 18.

= unknown.