Flora of North America species comparison

(7) 35-150 cm, erect, not rooting at the lower nodes.

5-55 cm, erect, glabrous.

mostly basal, sometimes forming a dense 10-35 cm tuft;

sheaths glabrous;

ligules 2-13 mm, scarious, decurrent, obtuse to acute;

blades 5-30 cm long, usually at least some flat and 1-4 mm wide, the remainder folded or rolled and 0.5-1 mm in diameter, adaxial surfaces with 5-11 prominent ribs, ribs usually all papillose, scabridulous, or scabrous, sometimes puberulent, outer ribs sometimes more strongly so than the inner ribs.

often forming a basal tuft;

sheaths glabrous;

ligules 1-4.5 mm, acute or acuminate, entire;

blades 2-12 (16) cm long, usually 0.3-0.8 mm in diameter, folded or convolute, 0.5-2 mm wide when flat, abaxial surfaces glabrous, adaxial surfaces glabrous or sparsely hirtellous, sometimes scabrous, blades of flag leaves 0.8-3 cm.

8-30(40) cm, 4-30 cm wide, usually open and pyramidal, sometimes contracted and ovate;

branches straight to slightly flexuous, usually strongly divergent, sometimes strongly ascending, lower branches often scabridulous or scabrous, particularly distally, with not or only moderately imbricate spikelets.

1.5-10(12) cm long, 0.5-2(11) cm wide, usually dense, oblong-ovate to narrowly cylindrical;

branches 1-3.6(6) cm, straight, usually stiff, erect to ascending, usually smooth or almost so, scabrules separated by 0.2+ mm, spikelet-bearing to near the base.

2.5-7.6 mm, ovate to V-shaped, laterally compressed, usually bisexual, sometimes viviparous, bisexual spikelets usually with 2(3) florets, rarely with 1.

2.3-6 mm, ovate to obovate, with 2(3) florets.

lanceolate, acute;

lower glumes 2.7-7 mm, entire, 1-3-veined, midvein sometimes scabridulous, at least distally;

upper glumes 2-7.5 mm, 1-3-veined, lanceolate, midvein smooth or wholly or partly scabridulous;

callus hairs 0.2-2.3 mm;

lemmas 2-5(7) mm, smooth, shiny, glabrous, usually purple over less than 1/2 their surface, purple or green proximally, if green, often with a purple band about midlength, usually green or pale distally, usually awned, awns (0.5)1-8 mm, attached from near the base to about midlength, straight or geniculate, sometimes exceeding the glumes;

anthers 1.5-3 mm.

subequal to equal, 2.5-5.6 mm, purplish over more than 1/2 their surface, lanceolate, smooth, acuminate or acute;

lower glumes 1-veined, smooth;

upper glumes exceeding to exceeded by the lowest floret, 3-veined;

callus hairs 0.2-2 mm;

lemmas 2.2-4 mm, oblong or lanceolate, smooth, shiny, glabrous, awns (0.2)0.7-4 mm, usually equaling or exceeding the lemmas, straight or weakly geniculate, usually attached from near the base to midlength, occasionally connate almost their full length;

anthers 1.2-2.5 mm.

0.5-1 mm.

voucher specimens for these counts have not been examined.

= 18, 24, 25, 26-28, about 39, 52.

= 26, 27, 28, about 50, 52.