Flora of North America species comparison

15-65 cm, erect to spreading, often geniculate-based, sometimes nearly prostrate, usually much-branched.

45-80 cm, erect, usually unbranched.

cauline;

sheaths shorter than the internodes, not disintegrating into threadlike fibers at maturity, glabrous or sparsely pilose, hairs on the throat sometimes to 5 mm;

collars glabrous;

ligules about 0.5 mm;

blades 5-14 cm long, 1-2 mm wide, flat to loosely involute, light green.

basal and cauline;

sheaths 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 5-15 cm long, about 0.5 mm wide, usually involute, occasionally loosely folded, glabrous, light green.

usually paniculate, occasionally racemose or spicate, 6-22 cm long, 1-4(6) cm wide;

nodes glabrous or with straight hairs, hairs to 0.3 mm;

primary branches 1-4 cm, appressed to erect, rarely somewhat spreading distally, without axillary pulvini, with 2-5 spikelets per branch.

paniculate, 12-20 cm long, 2-8 cm wide;

primary branches 2-5 cm, erect to horizontal, with or without axillary pulvini, with 1-5 spikelets.

widely spaced to crowded.

appressed or with axillary pulvini and spreading.

2-11 mm, subequal, 1-veined, acuminate, unawned or awned, awns to 1 mm;

calluses less than 1 mm;

lemmas 2.5-10 mm, gray to dark purplish-brown, often horizontally banded or mottled, scabrous-hispid or glabrous, not beaked, apices only slightly narrowed, junction with the awns not evident;

awns usually unequal, terete and curving up to 100° at the base, erect to reflexed distally, not disarticulating at maturity;

central awns 1-27 mm;

lateral awns absent or to 18 mm, shorter than the central awns;

anthers 1 and 0.2-0.3 mm, or 3 and 3-4 mm.

6-10(12) mm, equal or the lower glumes slightly shorter, 1-veined, brownish;

calluses about 0.5 mm;

lemmas (6)7-14(16) mm, mostly smooth, mottled, terminating in a 2-4 mm, usually twisted, scabrous beak;

central awns 5-10 mm, sharply curved at the base, spreading distally;

lateral awns absent or to 3 mm, erect;

anthers 3, about 1.5 mm, brown.

3-4 mm, light brown.

5-8 mm.

= unknown.

= unknown.