Senecio occidentalis (A. Gray) Greene var. rotundatus Rydberg

Plants mostly 1–2 dm. Stems arching upward. Leaves (± equally developed along stems) usually smaller than 4 × 2 cm, bases not clasping, margins toothed or subentire. Heads (1–)3–5. Phyllaries (± 8) ± 13, (7–)8–10 mm.

Flowering summer. Talus slopes, rocky sites, subalpine and high coniferous associations; 2500–3500 m; Alta., B.C.; Calif., Idaho, Mont. Nev., Oreg., Utah, Wash., Wyo.

Variety fremontii grows in the northern Rocky Mountains and interior ranges. Apparently, the plants intergrade locally with Senecio spartioides in the mountains of the Great Basin.