Perennials, 3-10(-12) cm; rhizomatous, fibrous-rooted, rhizomes or caudices simple, relatively short and thick. Stems erect, densely cobwebby-lanate (hairs white), eglandular. Leaves basal (persistent) and cauline; blades oblanceolate to subspatulate, (10-)20-60 × 2-10 mm, margins entire, faces lanate, eglandular; cauline blades oblong to linear-oblong, gradually reduced, bractlike. Heads 1. Involucres 8-10 × 12-20 mm. Phyllaries in 2(-3) series (purple beneath pubescence), densely and closely lanate, sparsely glandular (glandularity obscured). Ray florets 60-100; corollas white, often drying pinkish, 8-13 mm (mostly 1-2 mm wide), laminae coiling. Disc corollas 3.5-5 mm. Cypselae 1.9-2.2 mm, 2-nerved, faces strigose-hirsute; pappi: outer of setae, inner of 13-20 bristles. 2n = 18.

Flowering Jul-Aug. Rocky slopes and ridges, tundra, gravel barrens, sandstone outcrops; of conservation concern; 300-1000 m; Yukon; Alaska.

Erigeron muirii is known from Herschel Island in northern Yukon. Its densely lanate vestiture gives the whole plant a gray-green aspect.