Perennials, (20-)30-40(-60) cm (rhizomes suberect or weakly spreading). Herbage lanate-arachnose or tomentose, unevenly glabrescent. Stems 1(-2). Leaves (often purplish abaxially) reduced distally; petiolate; blades ovate to subelliptic, (5-)6-10(-15) × (2.5-)3-5(-9) cm, bases tapered or contracted, margins subentire to denticulate (denticles callous; mid and distal leaves bractlike). Heads (2-)5-12(-20) in corymbiform arrays. Calyculi of 2-5+ bractlets (largest to 3 mm). Phyllaries (± 13) ± 21, 5-7 mm, tips green. Ray florets ± 13; corolla laminae 5-10 mm. Cypselae hairy (especially on angles). 2n = 40. Flowering late spring-summer. Openings in pine-oak woodlands; 1600-2100 m; Ariz. Senecio arizonicus is reputedly in southern New Mexico (W. C. Martin and C. R. Hutchins 1980); that seems unlikely and should be checked.
FNA 2006, Kearney and Peebles 1969, McDougall 1973
Duration: Perennial Nativity: Native Lifeform: Forb/Herb General: Herbaceous perennials, to 40 cm tall, stems 1-2, herbage glabrescent to white-tomentose throughout, roots with weakly erect or spreading rhizomes. Leaves: Alternate, basal and cauline, the basal in a rosette, often purplish beneath, becoming reduced distally; blades petiolate, ovate to subelliptic, 6-10 cm long and 3-5 cm wide, bases tapered or contracted, margins subentire to denticulate. Flowers: Heads radiate, rays yellow, 13 or more, disk flowers yellow, involucres with row of bracts around outer calyx of 2-5 or more bractlets, phyllaries 21 or more, 5-7 mm long, with green tips, the heads borne in groups of 5-12 in corymbiform arrays. Fruits: Achenes hairy, especially on the angles. Pappus of numerous, white, soft, capillary bristles. Ecology: Found in openings in pine-oak woodlands, from 5,500-7,000 ft (1676-2134 m); flowering April-July. Distribution: Arizona. Ethnobotany: Unknown Etymology: Senecio is from senex, old man, which refers to the gray hairs on the seeds, while arizonicus means of or from Arizona. Synonyms: None Editor: LCrumbacher 2011