Flora of North America species comparison

(10)50-140 cm, stout, stiffly erect, branched from the middle and lower nodes;

lower nodes sericeous;

lower internodes sericeous, hairs papillose-based, upper internodes sometimes glabrous.

50-200 cm, strongly compressed, decumbent-erect, glaucous;

nodes glabrous.

rounded, glabrous or sparsely to densely hispid, hairs not fragile and prickly, not causing skin irritation, margins ciliate;

ligules 1-3 mm;

blades 3-60 cm long, 2-12 mm wide, flat or involute, ascending, adaxial surfaces densely hirsute basally, less densely so elsewhere, bases attenuate, apices acute.

keeled, glabrous or pubescent near the throat, upper sheaths much shorter than the internodes;

ligules 0.5-2 mm, membranous, dissected ciliate;

blades 20-35 cm long, 7-17 mm wide, flat, glabrous on both surfaces or the adaxial surfaces sparsely pilose.

(4)15-40 cm long, (3)10-25 cm wide, about 1/3 – 1/2 as long as the plants, open, breaking at the base of the peduncles at maturity and dispersed as tumbleweeds, secondary branching mostly confined to the distal 1/3 of the primary branches;

rachises densely hispid or glabrous;

lower primary branches in whorls of 4-7, stiffly spreading, naked on the lower 1/2;

pedicels 3-20 mm, appressed.

12-50 cm, about 2/3 as wide, open;

primary branches spreading, often verticillate at the lower nodes;

pedicels 0.2-4 mm, scabrous, spreading.

2-3 mm long, 0.8-1.2 mm wide, glabrous.

2.5-3.4 mm long, about 1.2 mm wide, ellipsoid, glabrous.

1-1.6 mm, 5-veined, acuminate;

upper glumes and lower lemmas similar, 2-2.8 mm, 7-9-veined, exceeding the upper florets by about 0.3 mm;

lower florets sterile;

lower paleas 1.4-2.2 mm;

upper florets 1.5-1.9 mm long, 0.7-1 mm wide, smooth, chestnut brown at maturity.

usually shorter than 1.7 mm, up to 1/2 as long as the spikelets, 3-veined, subacute;

upper glumes and lower lemmas subequal, scarcely longer than the upper florets, 5-veined;

lower florets sterile or staminate;

upper florets 2.9-3 mm long, about 1 mm wide, ellipsoid, glabrous, dull, pale, obscurely transversely rugose, apices minutely pubescent.

= 36.

= unknown.