Willamette fleabane

Perennials, 5–60 cm (colonial); taprooted, caudex branches rhizomelike plants. Stems (often purplish) erect or decumbent at bases, sparsely strigillose (basal cells inclined, hairs even-width), eglandular. Leaves basal (often withering by flowering) and cauline; basal blades linear to narrowly oblanceolate, 50–120(–180) × 3–6(–11) mm, cauline 3-nerved, gradually reduced distally, margins entire, faces hirtellous, eglandular. Heads (1–)2–5(–18) borne singly or in loosely corymbiform arrays. Involucres (4.5–)5–6 × 9–12 mm. Phyllaries in 2–3(–4) series (linear-lanceolate, apices linear-acuminate), sparsely to moderately villous, eglandular. Ray florets 26–57; corollas white to bluish, sometimes drying pinkish to pale blue, 7–12 mm, laminae not coiling or reflexing. Disc corollas 3–3.5 mm. Cypselae 1.2–1.6 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae , inner of (6–)12–16 bristles.

Flowering May–Jul. Heavy soils in seasonally wet or dry upland prairie grasslands; of conservation concern; 100–300 m; Oreg.

Erigeron decumbens is in the Center for Plant Conservation’s National Collection of Endangered Plants.