Flora of North America species comparison

50-120 cm, glabrous.

18-40(60) cm, mostly scabrous or puberulent below the inflorescence.

closed for less than 1/3 their length, glabrous, shredding into fibers;

Iigules (0.2)0.5-1.5 mm;

blades 2-8 mm wide, flat or loosely convolute, smooth or scabrous, veins 9-35, ribs obscure;

abaxial sclerenchyma in narrow strands;

adaxial sclerenchyma developed;

girders or pillars usually associated with the major veins.

closed for less than 1/3 their length, smooth or scabrous, glabrous or finely puberulent, persistent;

collars glabrous;

ligules 0.1-0.4 mm;

blades 0.2-0.4(0.6) mm in diameter, conduplicate, abaxial surfaces smooth, adaxial surfaces scabrous, veins 5(7), ribs 1, distinct;

abaxial sclerenchyma forming a continuous or almost continuous band;

adaxial sclerenchyma absent.

(5)10-20 cm, open, with 1-2 branches per node;

branches lax, ascending to spreading, spikelets clustered towards the ends of the branches, closely imbricate.

1-6(14) cm, usually contracted, with 1-2 branches per node;

branches usually erect, lower branches with 2+ spikelets.

4-7(7.5) mm, elliptic to obovate, with 3-5(8) florets.

3-6(6.5) mm, with 2-6(8) florets.

lanceolate to ovate-lanceolate, scabrous at least on the veins;

lower glumes (2.5)3-4(5) mm, usually almost as long as the adjacent lemmas;

upper glumes (3.5)4-5(5.5) mm;

lemmas 4-5(5.2) mm, stiffly chartaceous, ovate to obovate, glabrous, somewhat acute, unawned;

paleas as long as or slightly shorter than the lemmas, intercostal region smooth or scabrous distally;

anthers (0.7)1-2(2.5) mm;

ovary apices pubescent.

exceeded by the upper florets, ovate-lanceolate to lanceolate, glabrous;

lower glumes 1-2.5 mm;

upper glumes (1.7)2-3(3.9) mm;

lemmas 2.3-4(4.4) mm, obtuse to acute, mostly smooth and glabrous, sometimes scabrous or pubescent distally, unawned, sometimes mucronate, mucros to 0.4 mm;

paleas about as long as the lemmas, intercostal region smooth or scabrous distally;

anthers (1)1.5-2.2 mm;

ovary apices glabrous.

= unknown.

= 14 (28).