Flora of North America species comparison

(3)10-50(80) cm, often highly branched above the base.

20-60(75) cm, erect, unbranched.

cauline, glabrous;

sheaths shorter than the internodes, not disintegrating into threadlike fibers;

ligules 0.4-1 mm;

blades 2-14 cm long, 1-2.5 mm wide, flat to involute.

basal and cauline;

sheaths usually longer than the internodes, glabrous except at the summit;

collars densely pilose, hairs 1-3 mm, cobwebby and tangled, often deflexed;

ligules less than 0.5 mm;

blades 4-28 cm long, less than 1 mm wide, usually involute, infrequently flat, usually arcuate, abaxial surfaces glabrous, adaxial surfaces glabrous or puberulent near the base, scabrous or puberulent distally.

panicles, 5-15(20) cm long, 0.5-3 cm wide, often interrupted below;

nodes glabrous or with straight, less than 0.5 mm hairs;

primary branches 1-4 cm, erect to ascending, without axillary pulvini, with 3-8 spikelets.

paniculate, 10-20 cm long, 3-10(12) cm wide;

rachis nodes usually glabrous, sometimes with straight, less than 0.3 mm hairs;

primary branches 2-11 cm, stiffly ascending to spreading, with axillary pulvini;

secondary branches and pedicels with or without pulvini;

terminal spikelets often divergent.

crowded.

clustered on the distal 1/2 of the branches.

unequal, 1-veined, acuminate;

lower glumes 4-8 mm;

upper glumes 6-11 mm;

calluses 0.5-0.8 mm;

lemmas 6-9 mm, slightly keeled, midveins scabrous, junction with the awns not evident;

awns not disarticulating at maturity, flattened and straight to somewhat curved at the base, central rib flanked by equally wide pale wings;

central awns 7-15(20) mm;

lateral awns somewhat shorter, occasionally only 1-2 mm;

anthers 3, 0.3-0.7 mm.

equal or subequal, 1-veined, acuminate or awned, awns to 6 mm, brownish;

lower glumes 5-10 mm;

upper glumes 6-12 mm;

calluses 0.5-1 mm;

lemmas 7-13 mm, terminating in an obscure, narrow beak 1-4 mm long, 0.1-0.2 mm wide, junction with the base of the awns not evident;

awns 6-15 mm, not disarticulating at maturity, central and lateral awns similar in length and thickness, spreading to horizontal;

anthers 3, 1-3 mm, brown.

6-8 mm, tan.

= 22.

= unknown.