Senecio hartwegii Bentham, Pl. Hartw., 18. 1839 (as hartwegi)

Stems often marked with purplish spots or striae. Leaves: petioles mostly 3–7 cm; blades (ultimate venation raised and finely reticulate) mostly 10–20 × 10–20 cm (smaller distally), bases cordate to truncate, faces sometimes initially sparsely hirsute (only bases of hairs remaining at flowering). Phyllaries mostly 4–6 mm. Ray corolla laminae mostly 3–4 × 1.5–2 mm. Disc corollas 6–8 mm, tubes usually glandular-puberulent. Cypselae (1–)2.5 mm; pappi 4–6 mm. 2n = 60.

Flowering late summer–fall. Pine-oak forests, waste places, roadsides; 1200–1800 m; Ariz., N.Mex.; Mexico.