Siskiyou Mountain ragwort

Senecio macounii Greene, Pittonia 3: 169. 1897; S. fastigiatus Nuttall 1841, not Schweinitz ex Elliott 1823; S. fastigiatus subsp. macounii (Greene) Greenman; S. leucocrinus Greene; S. ligulifolius Greene; S. spatuliformis A. Heller

Perennials, 30–40+ cm; taprooted (caudices ± branched, becoming rhizomiform). Stems 1, sparsely to densely tomentose or glabrescent. Basal leaves (and proximal) petiolate; blades lanceolate to oblanceolate, 30–50+ × 10–20 mm, bases tapering, margins entire or shallowly toothed (slightly revolute). Cauline leaves gradually reduced (distal sessile, bractlike). Heads 6–15+ in corymbiform arrays. Peduncles inconspicuously bracteate or ebracteate, sparsely tomentose to glabrate. Calyculi 0 or inconspicuous. Phyllaries 13 or 21, green, 5–7+ mm, glabrous. Ray florets 8(–13); corolla laminae 8–10+ mm. Disc florets 30–40+; corolla tubes 2.5–3.5 mm, limbs 2–3 mm. Cypselae 1.5–2 mm, glabrous; pappi 4–5 mm. 2n = 46, 92.

Flowering early May–early Jul. Along streams, roadsides, clearings, disturbed sites, rocky soils, coniferous woodlands; 400–1400 m; B.C.; Calif., Oreg., Wash.

Packera macounii is similar in overall morphology to P. cana. Leaves of P. macounii are narrower and frequently revolute. It is often cited as being collected on serpentine soils; it is not restricted to them. Senecio fastigiatus Nuttall (1840) is a later homonym of S. fastigiatus Schweinitz ex Elliott (1823), a name of uncertain application.