Ahart's sulphur flower

Shrubs, spreading to rounded, 3-8 × 5-13 dm. Aerial flowering stems erect, 1-2 dm, mostly tomentose or at least densely floccose, without one or more leaflike bracts ca. midlength. Leaves in loose rosettes; blade elliptic to broadly elliptic or ovate, 1-2.5(-3) × 0.7-1.5 cm, densely rusty-lanate to tomentose abaxially, floccose or glabrous and olive green adaxially, margins plane. Inflorescences compound-umbellate, branched 3-4 times; branches tomentose to floccose, without a whorl of bracts ca. midlength; involucral tubes 2.5-4 mm, lobes 2-3 mm. Flowers 5-8 mm; perianth bright yellow.

Flowering Jun-Sep. Serpentine slopes, oak and conifer woodlands; 400-1000(-2000) m; Calif.

Variety ahartii is restricted to the Paradise and Lumpkin Ridge areas of Butte County. These large shrubs are among the more elegant of the sulphur flowers and are worthy of widespread cultivation.