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.Flora of North America, Erigeron pinnatisectus (A. Gray) A. Nelson, 1899. Feather-leaf fleabane Nelson, Aven 1899. Bulletin of the Torrey Botanical Club 26(5): 246
