Culms 20-80 cm tall, 1.5-2 mm thick, mostly glabrous, pubescent below the nodes. Basal sheath margins hairy distally, hairs 1-3.2 mm; blades 11-30+ cm long, 2.5-4.2 mm wide, usually flat or only partly closed, sometimes completely convolute, straight to somewhat arcuate distally. Panicles 11-15 cm long, 2-4 cm wide. Florets 5.5-6.5 mm; awns 15-35 mm; paleas sparsely hairy between the veins, hairs about 1/2 as long as the lemma hairs, apices usually rounded, occasionally somewhat pinched; anthers 3.5-4.5 mm, glabrous. Caryopses 5-6 mm, fusiform. 2n = unknown.

Achnatherum parishii subsp. parishii grows on dry, rocky slopes, in desert shrub and pinyon-juniper associations, from the coastal ranges of California to northeastern Nevada, eastern Utah, and the Grand Canyon in Arizona. Its range extends into Baja California, Mexico. It differs from A. coronatum in its shorter culms and once-geniculate awns, and from subsp. depauperatum in its longer culms, hairy sheath margins, and sparsely hairy paleas.