Erigeron pinnatisectus (A. Gray) A. Nels.

Perennials, 4–11 cm; taprooted, caudex branches usually relatively thick, woody. Stems erect, sparsely to moderately hispidulous and minutely glandular, sometimes merely glandular. Leaves mostly basal and proximal (persistent); basal blades spatulate to obovate (often folding), 20–40(–50) × 5–10 mm, margins pinnatifid (lobes linear), faces usually glabrate, sometimes sparsely hirsute, usually minutely glandular; cauline blades mostly linear, abruptly reduced distally or nearly absent, margins entire, usually coarsely ciliate. Heads 1. Involucres 5.5–8 × 9–13 mm. Phyllaries in 3–5 series, sparsely hispidulous to hirsuto-villous, minutely glandular. Ray florets 40–70; corollas usually light blue, sometimes slightly purplish, drying bluish or fading lighter, 7–12 mm, laminae reflexing. Disc corollas 3.8–4.5 mm. Cypselae 1.5–1.8 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner (persistent) of 25–30 bristles, with outer setae.

Erigeron compositus Pursh var. pinnatisectus A. Gray, Notes Compositae, 90. 1880

Erigeron pinnatisectus is a species of flowering plant in the family Asteraceae known by the common name feather-leaf fleabane. It is native to the Rocky Mountains of Wyoming, Colorado, and New Mexico.

Erigeron pinnatisectus is a small perennial herb rarely more than 11 centimeters (4.4 inches) tall, producing a woody taproot. The leaves are covered with wool. The plant generally produces only 1 flower head per stem. Each head has 40–70 purple or pale blue ray florets surrounding numerous yellow disc florets. The plant grows on buffs, ledges, and steep slopes at high altitudes, often above tree line.

Erigeron pinnatisectus là một loài thực vật có hoa trong họ Cúc. Loài này được (A.Gray) A.Nelson mô tả khoa học đầu tiên năm 1899.