Flora of North America species comparison

15-55 cm, slender, erect or radiating from a large tuft of predominantly basal leaves, lower internodes short, upper 3-5 internodes elongate;

nodes bearded with soft, spreading or retrorse hairs;

internodes glabrous;

fall phase branching extensively from the basal nodes, forming a dense cushion that overwinters.

50-150 cm, usually robust, erect;

nodes often swollen, densely bearded with thin retrorse hairs above a constricted, glabrous, viscid ring;

internodes grayish-purple, velvety-pubescent;

fall phase branching from the mid- and upper culm nodes, with long, repeatedly forking and often recurving branches, ultimately with fascicles of reduced blades and included secondary panicles.

2-4;

sheaths usually longer than the internodes, pilose, hairs to 4 mm, retrorse or spreading;

ligules 0.2-1 mm, at low magnification appearing to be membranous and ciliate, at high magnification evidently of hairs that are coherent at the base;

blades 4-17 cm long, 4-12 mm wide, lanceolate, at least 3/4 as long as the basal blades, spreading to suberect, thin, soft, lax, yellowish-green, nearly glabrous or densely pilose on 1 or both surfaces, margins usually finely short-ciliate, at least on the basal 1/2, cilia not papillose-based.

7-11;

sheaths not overlapping, narrowing distally, lustrous, bases sparsely to densely retrorsely villous, hairs papillose-based, summits purplish, with yellowish spots;

collars densely villous;

ligules 0.5-2 mm, of hairs;

blades 9-20 cm long, 9-20 mm wide, thick, densely soft pubescent, bases rounded to subcordate, margins ciliate basally.

1.7-2.3 mm long, 1-1.2 mm wide, broadly ovate or oblong-obovoid, with papillose-based hairs, obtuse.

2.2-2.8 mm long, 1.3-1.5 mm wide, ovoid-ellipsoid, often purplish basally, prominently veined, margins and apices sparsely to densely pubescent, hairs papillose-based.

1/4 - 1/3 as long as the spikelets, broadly deltoid;

upper glumes and lower lemmas subequal, usually fully covering the upper florets;

upper florets 1.5-1.8 mm long, 1-1.2 mm wide, broadly ellipsoid or obovoid, minutely umbonate.

0.6-1.3 mm, subtruncate to acuminate;

lower florets sterile;

upper florets minutely apiculate.

rosettes poorly differentiated;

blades ovate to lanceolate.

rosettes well-differentiated;

blades sometimes more than 10 cm, lanceolate.

panicles 4-12 cm long, 3-8 cm wide, well-exserted;

secondary panicles more compact, usually not exserted above the crowded basal leaves;

rachises and branches wiry, spreading or deflexed, often pilose.

panicles 6-16 cm long, 5-12 cm wide, well-exserted, dense;

rachises softly pubescent basally;

branches often mottled with purplish viscid spots, glabrous.

= 18.

= 18.