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.

20-60 cm tall, 0.8-1.2 mm thick, shortly decumbent to geniculate basally, erect distally;

nodes glabrous;

internodes 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.

shorter or longer than the internodes, rounded, smooth, glabrous;

ligules about 1 mm;

blades 5-15 cm long, 2-8 mm wide, flat, linear, glabrous or with a few marginal cilia near the base, bases contracted, apices long-acute.

(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.

10-20 cm long, 6-12 cm wide, exserted or partially included;

primary branches alternate, ascending to strongly divergent, developing secondary branches in the basal 1/3 – 1/2, pedicels 4-9 mm, ascending.

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

2.7-3.2 mm long, 1-1.2 mm wide, ovoid-ellipsoid, green tinged with purple, glaucous, glabrous, acute.

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.

0.7-1.1 mm, about 2/5 as long as the spikelets, acute to attenuate;

upper glumes and lower lemmas similar, equaling the spikelets, 11-13-veined, tapering to apiculate apices;

lower paleas 1-2 mm;

lower florets sterile;

upper florets about 2.2 mm, ellipsoid, smooth, shiny, yellow at maturity, apices acute.

= 36.

= 54.