Herbage glabrate or glabrous. Calyculi: bractlets well developed (lengths, at least some, 1 / 2 phyl-laries). Involucres campanulate. Phyllaries (± 13) ± 21, 7-10+ mm.
Flowering mostly summer-fall, less commonly spring. Open, rocky or sandy sites, especially desert basins and washes; 600-2000 m; Ariz., Calif., Nev., N.Mex., Tex., Utah; Mexico (Baja California).
Senecio flaccidus var. monoensis intergrades with var. douglasii and with var. flaccidus in areas of range overlap.