Flora of North America species comparison

20-210 cm, stout, not woody;

nodes puberulent;

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

30-130 cm, terete to slightly compressed.

laterally compressed, glabrous or sparsely to densely pilose or villous, especially at the summit;

ligules less than 0.5 mm, membranous, erose, often brownish;

blades 10-50 cm long, 4-12 mm wide, erect, adaxial surfaces pilose at least basally, glabrous or pilose abaxially.

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.

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.

10-40 cm, 1/4 - 2/3 as wide as long, well-exserted at anthesis;

branches relatively few, stiffly spreading or ascending; ultimate branchlets 1-sided;

pedicels 0.1-3 mm, scabridulous to scabrous, appressed.

4-6 mm, ovoid, usually glabrous.

2.3-3.9 mm, narrowly ellipsoid to ovoid, usually subsessile, usually pale to yellowish-green, glabrous, often falcate and gaping at the apices, rarely lanceolate, densely crowded on short, appressed branchlets, set obliquely on short pedicels.

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.

A-A as long as the spikelets, 3-veined, keels scabrous, apices acute;

upper glumes and lower lemmas subequal, keeled, beaked, usually gaping at the apices;

lower florets sterile;

lower paleas subequal to the lower lemmas;

upper florets 1.5-2.2 mm long, about 1 mm wide, 2/5 – 3/4 as long as the spikelets, apices with a tuft of minute, thick hairs;

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

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

= 18, 36.