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.

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

nodes glabrous.

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.

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.

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.

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.

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

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

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.

= 18.

= unknown.