Flora of North America species comparison

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

internodes glabrous or pubescent, sometimes nearly lanose.

55-110 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.

cauline;

sheaths shorter or longer than the internodes, glabrous, not disintegrating at maturity;

collars glabrous, or sparsely pilose at the sides;

ligules about 0.2 mm;

blades 5-25 cm long, 1-2 mm wide, flat or loosely folded, pale green, cauline leaves usually glabrous adaxially, innovation leaves pilose.

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.

spikelike racemes, 20-45 cm long, 1-2 cm wide;

nodes glabrous, with only 1 spikelet.

appressed.

solitary, not overlapping.

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.

9-11 mm, equal or the lower glumes slightly longer than the upper, narrowly oblong, often slightly falcate, tan to brown, 1-veined;

lower glumes occasionally with 1-2 faint lateral veins, awn-tipped, awns about 0.5 mm;

upper glume awned, awns 1-2.5 mm;

calluses 1-1.5 mm;

lemmas 7-10 mm, brown, lead-colored, or purplish, not beaked, junction with the awns not evident;

awns equally thick, not disarticulating at maturity;

central awns 14-20 mm, slightly longer than the lateral awns, strongly curved basally, distal portion reflexed;

lateral awns horizontal to reflexed;

anthers 3, about 4.5 mm, purplish.

4-5 mm, chestnut-colored.

= 22.

= unknown.