158. Erigeron bellidiastrum Nuttall, Trans. Amer. Philos. Soc., n. s. 7: 307. 1840.
Annuals (or biennials?), 3.5–30(–50) cm; taprooted. Stems erect to ascending, hirsutulous (hairs upcurved), usually eglandular, sometimes minutely glandular (var. arenarius). Leaves basal (sometimes persistent) and cauline or mostly cauline; blades linear to oblanceolate or spatulate, 10–60(–80) × 2–6(–9, or 15) mm, margins entire, lobed, or pinnately dissected, faces sparsely strigose, eglandular. Heads 1–12 usually in diffuse arrays (from branches beyond midstems or sometimes clustered distally). Involucres 3–5 × 5–7(–11) mm. Phyllaries in 2–3(–4) series, hispidulous, minutely glandular. Ray florets 22–70 (some positioned among inner phyllaries); corollas white, often with abaxial lilac midstripe, drying white to bluish, 4–7.5 mm, laminae not coiling or reflexing. Disc corollas 2.2–3 mm (throats indurate and inflated). Cypselae 1–1.6(–1.8) mm, 2-nerved, faces sparsely strigose; pappi: outer cartilaginous crowns, inner of 15–18 bristles.
Varieties 3 (3 in the flora): United States, n Mexico.
Erigeron bellidiastrum is recognized by its annual duration, upcurved hairs of the stem, relatively few rays, 1-seriate pappi, and by some ray florets consistently produced between the phyllaries, the mature cypselae of these held in place as the phyllaries reflex at maturity.