Flora of North America species comparison

10-75 cm, about 1 mm thick, simple or with erect basal branches;

nodes densely pilose, hairs ascending;

internodes glabrous or shortly pubescent distally.

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.

longer than the internodes, green to purplish, hispid, margins sparsely ciliate;

ligules 0.5-1.5 mm;

blades 3-32 cm long, 1-7 mm wide, ascending to erect, linear, narrowing basally, flat or the margins involute, surfaces sparsely hirsute or pilose (rarely glabrous), hairs near the base papillose-based, margins prominent, apices acute.

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.

5-45 cm long, 1-6 cm wide, at least 1/2 as long as the plants and 3 times longer than wide, open;

rachises glabrous;

primary branches usually alternate or subopposite, ascending to slightly divergent, secondary branches and pedicels attached to the distal 2/3;

secondary branches diverging;

pedicels 0.5-17 mm, ascending to 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.

2.5 - 3.7 mm long, 0.6-1.1 mm wide, narrowly ovoid, glabrous, acute;

lower glumes 0.8-1.3 mm, 1/3 – 1/2 as long as the spikelets, acuminate;

upper glumes 2.3-3.3 mm, 7-9-veined, exceeding the upper florets by about 0.6 mm;

lower florets sterile;

lower lemmas 2.2-2.7 mm, exceeding the upper florets by about 0.6 mm, 7- or 9-veined, apices scabridulous, pointed;

lower paleas absent;

upper florets 1.6-1.7 mm long, about 0.6 mm wide, usually smooth, usually pale, sometimes becoming dark at maturity.

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

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.