Annuals, biennials, or short-lived perennials, 2.5–8(–12, 18) cm; usually taprooted, sometimes fibrous-rooted, caudices simple or branched. Stems first erect (greenish proximally), then producing herbaceous, leafy, prostrate runners (stoloniform branches, sometimes with rooting plantlets at tips), densely hirsutulous (hairs spreading-deflexed, of relatively even lengths and orientations), sparsely minutely glandular. Leaves mostly basal (persistent in early season); blades oblanceolate to spatulate (obovate-elliptic laminae), 10–30(–60) × 3–6(–12) mm, cauline abruptly reduced distally, margins entire, dentate, or lobed, faces densely hirsute, eglandular. Heads 1(–3 rarely, from midstem or proximal branches). Involucres 3.5–4.5(–6) × 6–9(–12) mm. Phyllaries in 3–4 series, sparsely to moderately hirsute, minutely glandular. Ray florets 60–130; corollas white, often purplish abaxially, sometimes with an abaxial midstripe, 5–9 mm, laminae not coiling or reflexing. Disc corollas 2–3 mm (throats indurate and slightly inflated). Cypselae 0.7–1.3 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 12–16 bristles. 2n = 27.