Plants annual; tufted, without innovations, without glandular pits. Culms 10-80 cm, erect to geniculate or decumbent below, glabrous. Sheaths hirsute at the apices, hairs to 4 mm; ligules 0.2-0.5 mm; blades 2-20 cm long, 1-4.5 mm wide, flat to involute, abaxial surfaces glabrous and smooth, adaxial surfaces scabridulous. Panicles 5-25 cm long, 3-12 (15) cm wide, ovoid to pyramidal, usually open, sometimes contracted; primary branches 0.6-8.5 cm, appressed or diverging to 80° from the rachises, solitary or paired at the lowest 2 nodes; pulvini glabrous or sparsely hairy; pedicels 1-7 mm, flexible, appressed to widely divergent, sometimes capillary. Spikelets 3.5-11 mm long, 1.2-2.5 mm wide, linear-oblong to narrowly lanceolate, plumbeous, yellowish-brown, or dark reddish-purple, with 6-22 florets; disarticulation acropetal, paleas persistent. Glumes subulate to ovatelanceolate, hyaline; lower glumes 0.5-1.5 mm, at least 1/2 as long as the adjacent lemmas; upper glumes 1-1.7 mm, usually broader than the lower glumes; lemmas 1-2.2 mm, ovatelanceolate, hyaline to membranous, grayish-green proximally, reddish-purple distally, lateral-veins moderately conspicuous, apices acute; paleas 1-2 mm, hyaline to membranous, keels scabridulous, apices obtuse; anthers 3, 0.2-0.7 mm, purplish. Caryopses 0.5-1.1 mm, pyriform, slightly laterally compressed, smooth, faintly striate, brownish. 2n = 60.
Conn., N.J., N.Y., B.C., N.B., N.S., Ont., Que., Wash., Wis., Del., Ill., Ohio, Utah, Virgin Islands, D.C., Ark., Kans., Minn., N.Dak., Nebr., Okla., S.Dak., W.Va., Pacific Islands (Hawaii), Mass., Maine, N.H., R.I., Vt., Fla., Wyo., N.Mex., Tex., La., Tenn., Pa., Ga., Ky., Mich., Mont., Nev., Oreg., S.C., Va., Colo., Calif., Puerto Rico, Ala., Miss., N.C., Ind., Iowa, Md., Ariz., Idaho, Mo.
Eragrostis pectinacea is native from southern Canada to Argentina. In the Flora region, it grows in disturbed sites such as roadsides, railroad embankments, gardens, and cultivated fields, at 0-1200 m.
|1||Anthers 0.5-0.7 mm long||Eragrostis pectinacea var. tracyi|
|1||Anthers 0.2-0.4 mm long.||> 2|
|2||Pedicels appressed, rarely diverging to 20° from the branches||Eragrostis pectinacea var. pectinacea|
|2||Pedicels widely divergent, usually diverging 20-60° from the branches||Eragrostis pectinacea var. miserrima|
"decumbent" is not a number.