Plants perennial; rhizomatous, usually not cespitose. Culms 25-95 cm tall, 0.8-1.5 mm thick, erect or ascending; internodes smooth, shiny, and glabrous for most of their length, scabridulous immediately below the nodes. Sheaths glabrous, margins hyaline; ligules 0.3-1 mm, membranous, truncate, ciliolate; blades 4-16 cm long, 2-7 mm wide, flat, glabrous, usually smooth, occasionally scabridulous. Panicles 4-18 cm long, 0.2-0.8 cm wide, narrow, usually exserted; axillary panicles usually exserted, sometimes partially included in the subtending sheath; primary branches 0.6-4 cm, ascending to appressed; pedicels 0.3-1.6 mm, strigose. Spikelets 1.6-3 mm, erect, overlapping the next spikelet on the branch by 1/2 its length. Glumes equal to subequal, 1-2.5 mm, much shorter than the florets, scabridulous (particularly over the veins), 1-veined, narrowing from above the broad, overlapping bases to the acute apices, unawned or awned, awns to 1 mm; lemmas 1.6-2.8 mm, lanceolate, hairy on the calluses, lower 1/2 of the midveins, and margins, hairs 0.3-0.5 mm, apices acuminate, unawned or awned, awns to 1 mm; paleas 1.6-2.9 mm, lanceolate, basal 1/2 with hairs shorter than 1. 5 mm, apices scabridulous, acuminate; anthers 0.4-1 mm, yellow. Caryopses 1-1.5 mm, fusiform, brown. 2n = 40.
Conn., N.J., N.Y., Del., D.C., Wis., W.Va., Ont., N.H., Tex., N.C., Tenn., Pa., Mass., R.I., Vt., Va., Md., Ala., Ark., Ill., Ga., Ind., Iowa, Maine, Kans., Nebr., Okla., Ohio, Mo., Minn., Miss., Ky.
Muhlenbergia sobolifera grows in dry upland forests, oak woodlands, and on rock outcrops of sandstone, chert, or limestone formations, at elevations of 0-1200 m. It is restricted to the Flora region.