Rydberg’s fleabane

Perennials, 2.5–6 cm; taprooted, caudex branches relatively short, thick. Stems erect, finely hirsutulous to villosulous, eglandular. Leaves mostly basal (persistent); blades linear-oblanceolate to narrowly spatulate, 10–50 × 1–3 mm, cauline mostly on proximal ¹ / 2 of stems, reduced distally, margins entire (apices obtuse to rounded), abaxial faces glabrous, adaxial glabrous or sparsely villous, eglandular. Heads 1. Involucres 5–6 × 7–12 mm. Phyllaries in 2–3 series, densely and finely hirsuto-villous (hairs without colored cross walls), minutely and inconspicuously glandular. Ray florets 15–35; corollas usually bluish to purplish, rarely white, 6–9 mm, laminae coiling. Disc corollas 3.7–5 mm. Cypselae 1.8–2 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 15–20 bristles.

Flowering Jun–Aug. Open subalpine to alpine slopes; 2000–3200 m; Idaho, Mont., Wyo.