Flora of North America species comparison

10-40 cm, highly branched above the base in age;

internodes glabrous or pubescent, sometimes nearly lanose.

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

cauline;

sheaths shorter than the internodes, glabrous or puberulent;

collars glabrous or pubescent at the sides;

ligules 0.5-1 mm;

blades usually less than 6 cm long, 0.5-1 mm wide, pale green, involute, glabrous or puberulent abaxially.

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.

paniculate or racemose, 5-10 cm long, 1-2 cm wide, with few spikelets;

rachis nodes glabrous or with straight hairs;

primary branches 1-2 cm, appressed, without axillary pulvini.

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.

appressed.

clustered on the distal 1/2 of the branches.

unequal, 1-2-veined;

lower glumes 4-10 mm;

upper glumes 7-15 mm;

calluses about 1 mm;

lemmas 5-7 mm, purple or mottled, junction of the lemma and awns evident;

awns twisted together basally into a 4-26 mm column, free portions 12-50 mm, those of the central and lateral awns similar in length, curved to arcuate basally, straight and divergent distally, disarticulating at the base of the column at maturity;

anthers 3, about 2 mm long.

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.