Perennials, (8-)25-90 cm; taprooted, caudices woody.
Stems erect, sparsely hirsuto-villous (hairs 0.6-2 mm) or glabrous, densely stipitate-glandular (at least on distal
1 / 2 , glands relatively large, capitate).
Leaves basal (sometimes withering by flowering) and cauline; basal blades 15-60 × 8-37 mm, cauline gradually reduced distally, margins deeply pinnatifid, lobes 2-4(-5) pairs, faces usually glabrous, stipitate-glandular.
Heads (1-)5-25(-50) in loosely corymbiform arrays.
Involucres 4.5-5.5 × 8-12 mm.
Phyllaries in 3-4 series, glabrous or sparsely hirsute, densely stipitate-glandular.
Ray florets 75-130; corollas white, 8-14 mm, laminae reflexing.
Disc corollas 2.8-3.5 mm.
Cypselae 1-1.2 mm, 2-nerved, faces sparsely strigose;
pappi: outer of setae, inner (readily falling) of (8-)10-12 bristles.
2n = 18. Flowering Jul-Oct(-Nov). Open, rocky habitats, cliff ledges or crevices, grassland, chaparral, oak, pine, pine-fir; 1100-2800(-3100) m; Ariz., N.Mex.; Mexico (Chihuahua, Durango, Sonora).
Erigeron oreophilus is similar to
E. neomexicanus in its perennial habit, typically pinnatifid leaves, white, reflexing rays, and 10-12 readily falling pappus bristles; it has a vestiture of dense, viscid, stipitate glands and sparse, spreading, nonglandular hairs.