Erigeron corymbosus Nutt.

Perennials, 10–50 cm; taprooted, caudices usually with relatively slender and short, often woody branches. Stems ascending (often purplish proximally), hirsutulous (hairs spreading-deflexed), eglandular. Leaves basal (usually persistent) and cauline; basal blades linear-oblanceolate, (30–)60–160 × 3–8(–14) mm, cauline 3-nerved, gradually or little reduced distally (bases attenuate), margins entire (apices acute), faces hirsutulous, eglandular. Heads 1–10(–16) in loosely corymbiform arrays (on branches from distal ¹ / 2 of stems, often well beyond middle). Involucres 5–7 × 7–13 mm. Phyllaries in 2–3 series, flat, densely hirsute to hirsuto-villous, sometimes sparsely minutely glandular. Ray florets 35–65; corollas blue or less commonly pink, 7–13 mm, laminae coiling at apices. Disc corollas 4–5.3 mm. Cypselae 2–2.5 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 20–30 bristles. 2n = 18.

Erigeron corymbosus is a North American species of flowering plants in the family Asteraceae known by the common name long-leaf fleabane. It is found in western Canada (British Columbia) and the western United States (Washington, Oregon, Idaho, Montana, Wyoming, Utah).

Erigeron corymbosus is a perennial herb up to 50 cm (20 inches) tall, forming a taproot. Each branch produces an array of up to 16 flower heads, each head with 35–65 blue or pink ray florets plus numerous yellow disc florets.

Erigeron corymbosus là một loài thực vật có hoa trong họ Cúc. Loài này được Nutt. mô tả khoa học đầu tiên năm 1840.