Perennials, (10-)15-30 cm; rhizomatous, fibrous-rooted, caudices or rhizomes sometimes with relatively short or elongate, slightly woody branches. Stems ascending-erect, glabrous, sometimes minutely glandular distally. Leaves basal (often persistent) and cauline; basal blades spatulate to obovate or oblanceolate, (10-)40-80(-120) × 4-12(-15) mm, cauline equal-sized or gradually reduced distally (bases sometimes weakly subclasping), margins entire, faces glabrous, eglandular. Heads 1(-4). Involucres 5-7 × 9-14 mm. Phyllaries in 2-3(-4) series, glabrous, densely minutely glandular. Ray florets 20-45; corollas blue to purplish, 7-10 mm (mostly 1.5-3 mm wide), laminae coiling. Disc corollas 3.5-4.9 mm. Cypselae 1.5-1.7 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 12-15 bristles.

Flowering (May-)Jun-Aug(-Sep). Open, rocky slopes and streamsides, seeps, crevices in walls, meadows, pine to fir woods, chaparral, sometimes over serpentine; (50-)900-2300 m; Calif., Oreg.

Plants with relatively elongate basal leaves and cauline leaves little reduced distally (identified as Erigeron delicatus) are much different in general aspect; intermediates bridge the morphologic extremes.