Flora of North America species comparison

11-110 cm, erect to decumbent;

nodes shortly hirsute or glabrous.

35-150 cm, stout, compressed.

shorter than the internodes, greenish to purplish, glabrous or with papillose-based hairs, ciliate on 1 margin, glabrous on the other;

collars hirsute;

ligules 1.5-3.5 mm, of hairs;

blades 3-30 cm long, 3-30 mm wide, flat, usually hirsute or sparsely pubescent, hairs papillose-based, sometimes glabrous, bases rounded to cordate-clasping, margins ciliate, cilia papillose-based, apices acute.

more or less strongly compressed or keeled, sides usually glabrous or sparsely pubescent distally;

ligules 0.3-3 mm, membranous, erose or ciliate, cilia often themselves fimbriate;

blades 8-50 cm long, 2-12 mm wide, flat or folded, both surfaces usually glabrous or scabridulous, or the adaxial surfaces sparsely pilose basally.

9-30 cm long, 5-8 cm wide, erect or nodding, partially included to well-exserted, rachises glabrous or sparsely hispid basally;

primary branches usually alternate to opposite, divergent, secondary branches and pedicels confined to the distal 2/3;

pulvini inconspicuous;

secondary branches appressed;

pedicels 9-27 mm, appressed.

terminal and axillary, 9-40 cm, 1/3 – 3/4 as wide as long, usually dense; ultimate branchlets usually appressed, 1-sided, scabridulous;

pedicels 0.5-1.5 mm, usually appressed, sometimes with 1-several slender hairs at the apices.

1.9-4 mm long, 0.8-1 mm wide, ovoid to almost spherical, often reddish-brown, glabrous, veins prominent, scabridulous, apices abruptly acuminate.

usually 1.6-3.8 mm, usually subsessile, lanceolate, green, purple-tinged, or purple, glabrous.

1.3-2.4 mm, 1/2 - 3/4 as long as the spikelets, 3-5-veined;

upper glumes 1.8-3.3 mm, 7-11-veined;

lower florets sterile;

lower lemmas similar to the upper glumes, 9-veined;

lower paleas 0.4-0.9 mm;

upper florets 1.5-2.4 mm long, 0.4-0.8 mm wide, ellipsoid, smooth or conspicuously papillate, shiny, stramineous, often with a lunate scar at the base.

2/5 – 3/4 as long as the spikelets, 3-veined, midveins keeled;

upper glumes and lower lemmas subequal or the glumes slightly longer, often spreading slightly apart at the apices, midveins keeled, usually scabridulous apically;

lower florets sterile;

lower paleas to 2/3 as long as the lower lemmas;

upper florets 1.4-2 mm long, 0.6-0.8 mm wide, 2/5 – 3/4 as long as the spikelets, occasionally stipitate, lustrous, with a tuft of minute, thickish hairs at the apices;

upper lemmas thick, stiff, clasping the upper paleas throughout their length.

=18.