Flora of North America species comparison

8-100 cm tall, about 1 mm thick, erect to decumbent, simple to profusely branched;

nodes sparsely to densely pilose.

20-210 cm, stout, not woody;

nodes puberulent;

internodes usually with papillose-based hairs, sometimes nearly glabrous, not succulent.

often crowded basally;

sheaths rounded, usually longer than the internodes, hispid, hairs papillose-based, to 5 mm;

ligules 0.5-1.5 mm;

blades 3-30 cm long, 2-12 mm wide, linear, ascending to erect, flat, hirsute to sparsely pilose, greenish or purplish, bases truncate to subcordate and ciliate on the margins, apices acute.

numerous;

sheaths terete, densely pilose, with papillose-based and caducous hairs;

ligules membranous, ciliate, cilia 1-3 mm;

blades 15-40 cm long, 7-25 mm wide.

7-27 cm long, 4-24 cm wide, 1/4 - 1/3 as long as the plants, diffuse, usually exserted at anthesis, not breaking at the base of the peduncles to become a tumbleweed;

rachises glabrous or sparsely pilose basally;

primary branches spreading, secondary branches and pedicels confined to the distal 2/3 secondary branches diverging to appressed, with 1-4 spikelets;

pedicels 3-15 mm, spreading to appressed, scabrous or hirsute;

pulvini glabrous or pilose.

6-20 cm long, 4-11 cm wide, included or shortly exserted at maturity, dense;

branches stiff, appressed to spreading, spikelets solitary, confined to the distal portions;

pedicels 1-9 mm, scabrous and sparsely pilose.

1.4-2.4 mm long, 0.5-0.7 mm wide, usually green, glabrous.

4-6 mm, ovoid, usually glabrous.

0.5-0.9 mm, usually less than 1/2 as long as the spikelets, 3-4-veined, truncate to acuminate;

upper glumes 1.6-2 mm, 7-veined, veins not prominent;

lower lemmas 1.6-1.9 mm, 7-9-veined, veins not prominent;

lower paleas absent;

lower florets sterile;

upper florets 1.5-1.7 mm long, about 0.4 mm wide, often dark brown, sometimes disarticulating, apices minutely papillose.

2.8-3.6 mm, 1/2 - 3/4 as long as the spikelets, 5-7-veined, veins scabridulous distally, apices attenuate;

upper glumes 4-5.1 mm, slightly exceeding the upper florets, 11-13(15)-veined, veins scabridulous distally;

lower florets sterile;

lower lemmas 4-4.8 mm, slightly exceeding the upper florets, 9-13-veined, veins scabridulous distally;

lower paleas 1.2-1.6 mm, 1/2 or less the length of the upper florets, truncate to bilobed;

upper florets 3-3.8 mm long, 2-2.5 mm wide, smooth or striate, more or less shiny, stramineous to orange, red-brown, or blackish, persisting in the spikelets or disarticulating at maturity.

= 18.

= 36, 40, 42, 49, 54, 72.