Culms (15)30-65 cm tall, 0.8-2 mm thick, glabrous or hispidulous; nodes glabrous or densely villous. Ligules 0.2-0.6 mm; blades 5-10 cm long, 2-2.5 mm wide, flat in moist conditions, both surfaces pilose to villous, green. Panicles compact (rarely open), 5-10 cm long, 1-3 cm wide, usually 2-4(6) times longer than wide, occasionally interrupted in the lower 1/2; branches with 5-17 shortly pedicellate spikelets. Spikelets 7-11 mm, purplish to pale, with 3-15 florets; lower glumes 5-7 mm; upper glumes 6-9 mm, generally equaling or exceeding the lowest florets; lemmas 4-6 mm, awned from between the lobes, awns 1-3.5 mm, apices bilobed, lobes 1.5-2.5 mm, rounded to truncate, lateral veins forming a mucro to 1 mm; anthers 1, 1-1.5 mm. Caryopses 1.3-1.5 mm. 2n = 16.

Erioneuron nealleyi is found on rocky slopes in the southwestern United States and central Mexico. Stoloniferous plants are known only from central Mexico.