Ceanothus cordulatus

Ceanothus cordulatus is a species of shrub in the buckthorn family (Rhamnaceae) known by the common names Mountain Whitethorn and Whitethorn Ceanothus. It is native to California and adjacent sections of Oregon, Nevada, and Baja California, where it grows on mountain ridges and other forested areas. In California its major population is in the Sierras. This is a spreading shrub growing usually wider than tall and up to about 1.5 meters. The stems are gray, with the twigs yellow-green in color and fuzzy in texture when new. The evergreen leaves are alternately arranged and up to 3 centimeters long. Each is oval in shape with three ribs and generally not toothed. The leaves may be hairy or not. The flower cluster is panicle-shaped, up to about 4 centimeters long. The flowers are white to off-white with five sepals and five petals. The fruit is a rough, ridged capsule up to half a centimeter long. It has three valves inside, each containing a seed. This is a plant for high elevation gardens, from 4,000 ft. to 10,000 ft. At lower elevations it grows slowly and performs poorly. It is one of the most cold-tolerant of the Ceanothus.