Perennials, 30–40(–50) cm (caudices branched, fibrous-rooted). Herbage glabrous or with scattered hairs near leaf bases and among heads. Stems single or loosely clustered. Leaves evenly distributed; petiolate or subsessile; blades lanceolate, 4–10 × 2–4 cm, bases ± tapered, margins denticulate (distal leaves sessile, smaller). Heads (1–)3–5(–6) in cymiform arrays. Calyculi of 3–7 bractlets (0.5–3 mm). Phyllaries ± 13, 7–10 mm, tips black (hairy). Ray florets ± 8; corolla laminae ± 10 mm. Cypselae glabrous.

Flowering late Jul–mid Aug. Subalpine meadows and valleys; 1200–1800 m; B.C., N.W.T., Yukon.

Senecio sheldonensis is infrequently collected and poorly understood. The treatment here is provisional.