Taxon Report

Ceanothus hearstiorum Hoov. & Roof

Hearsts' ceanothus

Print Report

Taxon Summary

Ceanothus hearstiorum, commonly known as Hearsts' ceanothus, is a perennial evergreen shrub in the Rhamnaceae that is found only in California. It occurs within Chaparral (maritime), Coastal prairie, and Coastal scrub, growing at elevations from 75 to 245 meters. Ceanothus hearstiorum is ranked 1B.2, Plants Rare, Threatened or Endangered in California and Elsewhere; Moderately threatened in California.

Classification


Scientific Name:	Ceanothus hearstiorum Hoov. & Roof
Common Name:	Hearsts' ceanothus
Family:	Rhamnaceae
Element Code:	PDRHA040J0
USDA Plants Symbol:	CEHE2
Synonyms/Other Names:

Ecology and Life History


Lifeform:	perennial evergreen shrub
Blooming Period: Mar-Apr	Mar-Apr
Elevation:	75-245 (245-805)
General Habitats:	Chaparral, Coastal prairie, Coastal scrub
Microhabitat:
Microhabitat Details:

Conservation Status


CA Rare Plant Rank:	1B.2
Global Rank:	G1G2
State Rank:	S1S2
State List:	CR
Fed List:	None
Other Status:
CRPR Changes:

Occurrence Data from the CNDDB


Total Occurrences:	6
Element Occurrence Ranks:
Excellent (A)	0
Good (B)	1
Fair (C)	0
Poor (D)	0
None (X)	0
Unknown (U)	5

Location


California Endemic: True
California Counties and Islands: Name (Code)
San Luis Obispo (SLO)
Quads: Name (Quad Code)
Piedras Blancas (3512163), San Simeon (3512162)

Threat List Data from the CNDDB


Threat List Total:	5
EOs with Threat Listed:	Total EOs	% of EOs
	3	50 %
Foot traffic/trampling	2	33%
Grazing	2	33%
Other	2	33%
Development	1	16%
Improper burning regime	1	16%

Notes



Known from fewer than ten occurrences; need current status information. Possibly threatened by grazing. See Four Seasons 2:1-5 (1966) for original description.
Threats:

Taxonomy:

Selected References

Citation California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 4 November 2025].