Culms (10)15-50(95) cm; uppermost nodes usually in the lowest 1/3 of the culm. Uppermost sheaths usually longer than the blades; blades 1-16 cm long, 1.5-9 mm wide. Panicles 2.5-10(17) cm long, 0.7-3 cm wide; longest branches 0.5-4(6.5) cm, with 3-15(40) spikelets per branch; secondary branches usually appressed, spreading in warmer habitats. Spikelets (3)4-6.5 mm. Glumes subequal; lower glumes 1.8-4.5 mm, 1(-3)-veined; upper glumes 2.3-5.5 mm, usually about 1 mm shorter than the lemmas, (1-)3-veined; lemmas 3-6.5 mm; anthers 1.8-4 mm. 2n = 56.

Arctagrostis latifolia subsp. latifolia is the common subspecies from the Arctic coast of Alaska to Nunavut, northern Quebec, and northern Greenland.