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.

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

nodes glabrous.

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.

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.

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.

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.

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.

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

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.