Regularity: Regularly occurring
Localities documented in Tropicos sources
United States (North America)
Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.
Global Range: Endemic to Napa County, California (Callizo and Fremont 1988).
Comments: Almost entirely restricted to ridgetops and west-facing slopes, seldom occurring lower than halfway down the hillsides; elevation 120-630 m. Grows in the chaparral community in dry, rocky, brushy places, usually in full sun. Substrate is invariably Sonoma volcanic. Does not frequently appear on disturbed sites (Callizo and Fremont 1988).
Molecular Biology and Genetics
Barcode data: Ceanothus purpureus
Statistics of barcoding coverage: Ceanothus purpureus
Public Records: 1
Specimens with Barcodes: 1
Species With Barcodes: 1
National NatureServe Conservation Status
Rounded National Status Rank: N2 - Imperiled
NatureServe Conservation Status
Rounded Global Status Rank: G2 - Imperiled
Reasons: This species is endemic to California, occurring in Napa, Sonoma and Solano counties. It is threatened by vineyard and residential development, and alteration of fire regimes.
Comments: The California Native Plant society reports that this species is threatened by agriculture, namely vineyard development, residential development and alteration of fire regimes (2001).
Ceanothus purpureus, with the common name Hollyleaf ceanothus, is a species of shrub in the buckthorn family Rhamnaceae. It is endemic to northern California, where it is known only from the Inner North Coast Ranges north of the Bay Area, mainly in Sonoma and Napa Counties. The largest remaining population of this shrub occurs on Mt. George near Napa, where it is protected in a botanical preserve.
The Ceanothus purpureus plant grows in woodland and chaparral habitat. It is spreading or erect in form, approaching 2 meters in maximum height. The woody parts are gray to reddish brown in color. The evergreen leaves are oppositely arranged and up to about 2.5 centimeters long. They are round to oval, wavy, and edged with spiny teeth, resembling the leaf of holly. The inflorescence is a small cluster of blue or purple flowers. The fruit is a horned capsule about half a centimeter long.