Flora of North America species comparison

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

internodes glabrous or pubescent, sometimes nearly lanose.

70-100 cm, erect, mostly 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.

cauline;

sheaths mostly longer than the internodes, mostly glabrous, summit with hairs;

collars mostly glabrous, sides usually with straight or wrinkled hairs;

ligules 0.2-0.3 mm;

blades 30-55 cm long, 1-2 mm wide, pale yellow-green, loosely involute, lax, glabrous abaxially, with scattered hairs adaxially.

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, 30-45 cm long, 5-25 cm wide, oblong to ovate;

primary branches single or paired, ascending and somewhat lax to stiffly divergent, with weakly developed axillary pulvini, spikelet-bearing to the base;

lowermost branches to 15 cm.

appressed.

mostly appressed.

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.

purplish-tinged, 1-veined;

lower glumes 10-14 mm;

upper glumes 8-9 mm;

calluses 0.5-0.7 mm;

lemmas 8-12 mm, gray mottled with purple or dark patches, narrowing to a slightly curved and twisted beak, junction with the awns not strongly marked;

awns not disarticulating at maturity;

central awns 10-25 mm, falcate;

lateral awns absent;

anthers 3, about 1 mm, brown.

6-7 mm, chestnut-colored.

= 22.

= unknown.