Flora of North America species comparison

40-210 cm;

internodes glaucous or not;

branches erect to ascending, usually straight, sometimes arching.

60-250 cm;

internodes not glaucous.

usually smooth, rarely somewhat scabrous;

ligules 0.2-1 mm, ciliate, cilia 0.2-1.3 mm;

blades 11-52 cm long, 1.7-6.5 mm wide, smooth and glabrous or sparsely to densely pubescent with spreading hairs.

smooth;

ligules 0.6-1 mm;

blades 20-70 cm long, 2-7 mm wide, usually glabrous or scabrous on the margins.

6-195 per culm; subtending sheaths (2.1)3.1-4.6(6.7) cm long, (1.7)3-3.8(5.6) mm wide;

peduncles usually (1)4-6(30) mm, with 2-7 rames;

rames (0.5)1.7-2.8(4.4) cm, sometimes exerted at maturity, pubescence sparse basally and increasing in density distally within each internode.

50-500; subtending sheaths 2.5-4.5 cm long, 2-3 mm wide;

peduncles 20-70 mm, with 2(3) rames;

rames 2-4 cm, exerted at maturity;

internodes filiform, densely and evenly pubescent, hairs 3-9 mm.

spikelets (2.6)3.5-3.8(4.7) mm;

callus hairs 1-3 mm;

keels of lower glume usually smooth below midlength, scabrous distally;

awns 6-21 mm;

anthers 1(3), 0.6-1.5 mm, yellow or purple.

spikelets 3-4 mm; unawned;

callus hairs 0.5-1 mm;

keels of lower glumes scabrous above the midpoint;

anthers 3, 1-1.4 mm.

spikelets vestigial to absent.

spikelets mostly vestigial or absent, 1-2 of those in the terminal units on each rame 3-5 mm and staminate.

= 20.

= 60, 120.