Biennials or perennials, 7-50(-70) cm; rhizomatous, caudices or rhizomes relatively short and thickened, simple or branched, usually appearing merely fibrous-rooted. Stems erect or slightly basally ascending, hirsute or hirsuto-villous to strigose or glabrate, eglandular. Leaves basal (persistent) and cauline; basal blades oblanceolate to oblanceolate-spatulate, 40-150 × 3-15 mm, margins usually entire, sometimes shallowly dentate, faces hirsute or hirsuto-villous to sparsely strigose or glabrate, eglandular; cauline blades usually becoming lanceolate, abruptly or gradually reduced distally (bases sometimes subclasping). Heads 1-15. Involucres 5-9 × 10-20 mm. Phyllaries in (2-)3-4 series (greenish) , hirsute to strigose, eglandular. Ray florets 125-175; corollas white to pink or blue, 8-15 mm, laminae (nearly filiform) coiling tardily at tips. Disc corollas 4-5.5 mm. Cypselae 1.2-1.5 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 16-20 bristles. Erigeron glabellus is recognized by its subsimple caudices and fibrous-rooted bases, relatively numerous rays with nearly filiform laminae, and nonglandular vestiture.