Plants 100-400 cm. Leaves 20-40 mm, usually circular in cross section; axillary leaves 1-2 per fascicle. Phyllaries: midnerves typically evident on proximal ¹ / 2 , outer and mid subapical resin ducts not strongly thickened. Florets 12-30. 2n = 18.

Flowering fall-winter(-spring). Fine, clayey soils; of conservation concern; 100-600 m; Calif; Mexico (Baja California).

Variety palmeri grows in San Diego County and northern Baja California.