Perennials, to 10 cm (rhizomes branching). Herbage (sometimes reddish-tinged, especially proximally) glabrous. Stems 1-3 (arching upward). Leaves evenly distributed (proximal often withering before flowering); obscurely petiolate or sessile; blades oblanceolate to lance-linear (sometimes with 1-2 lateral lobes), 2-4 cm × 3-5 mm, bases subdecurrent, weakly clasping, margins entire or wavy (often revolute). Heads 1(-4). Calyculi of 3-5+ (inconspicuous) bractlets. Phyllaries ± 13, 5-7(-8) mm. Ray florets ± 8; corolla laminae 5-10 mm. Cypselae glabrous.

Flowering summer. Talus slopes; of conservation concern; 3000-3700 m; Calif., Nev.

Senecio pattersonensis has the aspect of a depauperate S. fremontii with notably narrow leaves. Some plants in collections appear to be intergrades with S. spartioides.