Flora of North America species comparison

30-130 cm, terete to slightly compressed.

100-300 cm tall, 4-10 mm thick, decumbent, semi-woody at the base, simple or branching from the middle nodes, prophylls prominent, to 15 cm;

nodes contracted, pilose, sericeous;

internodes glabrous or with papillose-based hairs below the nodes.

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.

shorter or longer than the internodes, rounded, sparsely hispid, hairs papillose-based, thick, fragile, penetrating and irritating the skin when handled, margins glabrous or ciliate;

collars more densely pubescent than the sheaths, hairs papillose-based;

ligules 1.5-2 mm, with longer hairs immediately behind, growing from the base of the blades;

blades 20-50 cm long, 15-40 mm wide, spreading, flat or with involute margins, bases subcordate to cordate, margins glabrous or sparsely hairy.

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.

terminal, 25-45 cm long, 5-15 cm wide, lax, contracted to diffuse, not breaking at the base and becoming tumbleweeds, all or most secondary branches confined to the distal 1/3;

lower branches whorled;

pedicels 0.5-2 mm, appressed.

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.

1.8-2.5 mm long, 0.5-1 mm wide, narrowly ellipsoid, glabrous.

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.

0.7-1.4 mm, about 1/2 as long as the spikelets, 3-5-veined, acute to attenuate;

upper glumes and lower lemmas subequal, about as long as the spikelets, 7-11-veined;

lower florets sterile;

lower paleas 1.3-1.7 mm;

upper florets 1.2-1.6 mm long, 0.5-0.7 mm wide, glabrous, smooth, shiny, chestnut brown to dark brown.

= 18, 36.

= 36.