Flora of North America species comparison

35-80(100) cm, smooth, glabrous throughout;

nodes usually not exposed.

(40) 50-100(150) cm, glabrous, erect or decumbent at the base.

closed for less than 1/2 their length, usually glabrous, sometimes pubescent, strongly reined, persistent or slowly shredding into fibers;

collars glabrous;

ligules (0.2)0.3-0.8(1) mm;

blades 0.5-1.3 mm in diameter when conduplicate, to 2.5 mm wide when flat, persistent, abaxial surfaces glabrous and smooth, adaxial surfaces scabrous or pubescent, veins 5-9(12), ribs 5-9, blades of the lower cauline leaves usually reduced to stiff horny points, blades of the upper cauline leaves longer and more flexuous;

abaxial sclerenchyma in strands about as wide as the adjacent veins;

adaxial sclerenchyma developed;

pillars and girders often present.

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

ligules (0.2)0.5-1(2) mm;

blades (3)5-10 mm wide, flat or loosely convolute, glabrous or sparsely pilose, smooth or scabrous, veins (11)15-39, ribs obscure;

abaxial sclerenchyma in narrow strands;

adaxial sclerenchyma developed;

girders or pillars usually associated with the major veins.

(4)8-15 cm, open or somewhat contracted, with 1-2 branches per node;

branches lax, spreading or loosely erect, lower branches with 2+ spikelets.

13-25 cm, open, with 1-2(3) branches per node;

branches lax, usually reflexed, sometimes spreading, spikelets borne towards the ends of the branches, not or only slightly imbricate.

9-15 mm, with (2)3-6(7) florets.

4-5(7) mm, elliptic to ovate, with 2-4(6) florets.

exceeded by the upper florets, ovate-lanceolate to lanceolate, glabrous, smooth or scabridulous distally;

lower glumes (2.4)2.8-5 mm, distinctly shorter than the adjacent lemmas;

upper glumes 4.5-7(8.5) mm;

lemmas (4.8)6-8.5 mm, lanceolate to ovate-lanceolate, glabrous, smooth or slightly scabrous, apices acute, unawned or awned, awns 0.2-1.5(2) mm;

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

anthers (2)2.5-4(5) mm;

ovary apices densely pubescent.

ovate-lanceolate, scabrous on the veins and distal margins;

lower glumes 2.5-3.5 mm, usually distinctly shorter than the adjacent lemmas;

upper glumes 3-4(4.7) mm;

lemmas 3-4.5 mm, ovate-lanceolate to ovate, stiffly chartaceous, glabrous, obtuse or somewhat acute, unawned;

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

anthers (0.8)1-1.7(2.2) mm;

ovary apices pubescent.

= 28.

= 42.