Flora of North America species comparison

(35)50-90 (100) cm, erect, glabrous, smooth.

25-85 (100) cm, usually smooth, glabrous, occasionally scabrous below the inflorescences.

closed for less than 1/2 their length, glabrous, hirsute, or scabrous, persistent;

collars glabrous;

ligules 0.1-0.5 mm;

blades 0.5-1(1.2) mm in diameter, conduplicate, abaxial surfaces glabrous or puberulent, adaxial surfaces sometimes scabrous, glabrous or pubescent, veins (5)7-9, ribs 5-9, well defined;

abaxial sclerenchyma in 5-7 wide strands, sometimes confluent into a single band;

adaxial sclerenchyma absent.

closed for less than 1/2 their length, smooth or scabrous, rarely pilose, persistent;

collars glabrous;

ligules 0.2-0.6 mm;

blades (0.3)0.5-0.9(1.5) mm in diameter, conduplicate, abaxial surfaces smooth or scabrous, adaxial surfaces scabrous or pubescent, rarely pilose, often glaucous or bluish, veins (3)5(7), ribs (1)3-5, well defined;

abaxial sclerenchyma in 5-7 wide, irregular strands;

adaxial sclerenchyma absent.

(7)8-20(25) cm, loosely to densely contracted, with 1-2 branches per node;

branches erect to slightly spreading, lower branches with 2+ spikelets.

(5)7-15(20) cm, loosely contracted or open, with 1-2 branches per node;

branches usually somewhat spreading at maturity, sometimes erect, rarely reflexed, lower branches with 2+ spikelets.

9-13.5 mm, with 4-6 florets.

(5.8) 7.5-13.5(19) mm, with (2)4-7(9) florets.

exceeded by the upper florets, ovate-lanceolate, smooth or scabrous distally;

lower glumes (2)2.5-5 mm;

upper glumes 4-6.2 mm;

lemmas 5-7(8.2) mm, scabrous near the apices, awns (2)3-5 mm, terminal, usually more than 1/2 as long as the lemma bodies;

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

anthers (2.6)2.8-3.6(4) mm;

ovary apices glabrous.

exceeded by the upper florets, ovate-lanceolate to lanceolate, mostly smooth, sometimes scabrous distally;

lower glumes 2.4-5(6) mm;

upper glumes 3-6(8) mm;

lemmas 5-8.5(10) mm, scabrous at the apices, awns (1.5)3-6(7) mm, usually more than 1/2 as long as the lemma bodies;

paleas shorter than to about as long as the lemmas, intercostal region scabrous or puberulent distally;

anthers 2.4-4.5 mm;

ovary apices glabrous.

= unknown.

= 28.