Annuals, biennials, or short-lived perennials, 30-70 cm; fibrous-rooted, caudices simple, sometimes lignescent, sometimes producing rhizomes that bear leaf tufts at upturned ends. Stems erect or ascending, sparsely to moderately strigose to strigillose or hirsuto-strigillose (hairs usually ascending, rarely spreading, 0.1-1.2 mm), eglandular. Leaves basal (usually persistent through flowering) and cauline; basal blades spatulate to broadly or narrowly oblanceolate to linear, (10-)30-150(-170) × 5-15(-21) mm, cauline usually gradually reduced distally, continuing to near heads, margins entire or shallowly to deeply serrate or crenate, faces glabrous or glabrate to sparsely strigose or strigoso-hirsute, eglandular. Heads 10-200+ in loosely corymbiform to paniculiform-corymbiform arrays (on distal branches). Involucres (2-)3-4 × 5-12 mm. Phyllaries in 2-4 series, glabrous, strigose, or sparsely hirsute, sometimes minutely glandular. Ray florets 50-100; corollas white, less commonly pinkish or bluish, 4-6 mm, laminae coiling. Disc corollas 1.5-2.5 mm (throats sometimes slightly indurate and inflated). Cypselae (0.5-)0.9-1.2 mm, 2-nerved, faces sparsely strigose; pappi: outer crowns of setae or scales, inner 0 (rays) or of 8-15 bristles (disc).