Western ragwort

Senecio hesperius Greene, Pittonia 2: 166. 1891; S. auleticus Greene

Perennials, 7–15+ cm; fibrous-rooted (caudices relatively slender). Stems 1, glabrous or sparsely tomentose. Basal leaves (and proximal cauline) petiolate; blades ovate, oblanceolate, or spatulate, 10–30 × 5–20 mm, bases tapering, sometimes obtuse, margins entire, subentire, or dentate. Cauline leaves abruptly reduced (sessile, clasping; bractlike, entire). Heads 1–4+ in corymbiform arrays. Peduncles bracteate (bractlets red-tinged), densely lanate-tomentose. Calyculi conspicuous (bractlets narrow, red-tinged). Phyllaries (13–)21, green (tips red or dark red), densely tomentose proximally. Ray florets (8–)13; corolla laminae 6–10+ mm. Disc florets 35–50+; corolla tubes 2.5–3.5 mm, limbs 3–4 mm. Cypselae 1.5–2 mm, glabrous; pappi 5–6 mm. 2n = 46.

Flowering mid Apr–mid Jun. Serpentine derived soils, open woodland scrub; of conservation concern; 500–2500 m; Calif., Oreg.

Packera hesperia is known only from the Siskiyou Mountains.