Taxon Report

Arctostaphylos montana Eastw. ssp. ravenii (P.V. Wells) V.T. Parker, M.C. Vasey & J.E. Keeley

Presidio manzanita

Print Report

Taxon Summary

Arctostaphylos montana ssp. ravenii, commonly known as Presidio manzanita, is a perennial evergreen shrub in the Ericaceae that is found only in California. It occurs within Chaparral, Coastal prairie, and Coastal scrub, growing at elevations from 45 to 215 meters. Arctostaphylos montana ssp. ravenii is ranked 1B.1, Plants Rare, Threatened or Endangered in California and Elsewhere; Seriously threatened in California.

Classification


Scientific Name:	Arctostaphylos montana Eastw. ssp. ravenii (P.V. Wells) V.T. Parker, M.C. Vasey & J.E. Keeley
Common Name:	Presidio manzanita
Family:	Ericaceae
Element Code:	PDERI040J2
USDA Plants Symbol:
Synonyms/Other Names:	Arctostaphylos hookeri ssp. ravenii

Ecology and Life History


Lifeform:	perennial evergreen shrub
Blooming Period: Feb-Mar	Feb-Mar
Elevation:	45-215 (150-705)
General Habitats:	Chaparral, Coastal prairie, Coastal scrub
Microhabitat:	Serpentine
Microhabitat Details:	serpentinite outcrop

Conservation Status


CA Rare Plant Rank:	1B.1
Global Rank:	G3T1
State Rank:	S1
State List:	CE
Fed List:	FE
Other Status:
CRPR Changes:

Occurrence Data from the CNDDB


Total Occurrences:	7
Element Occurrence Ranks:
Excellent (A)	0
Good (B)	1
Fair (C)	0
Poor (D)	0
None (X)	5
Unknown (U)	1

Location


California Endemic: True
California Counties and Islands: Name (Code)
San Francisco (SFO)
Quads: Name (Quad Code)
San Francisco North (3712274), San Francisco South (3712264)*

Threat List Data from the CNDDB


Threat List Total:	5
EOs with Threat Listed:	Total EOs	% of EOs
	3	43 %
Development	2	28%
Disease	1	14%
Foot traffic/trampling	1	14%
Insufficient population/stand size	1	14%
Non-native plant impacts	1	14%

Notes



Known from only one extant native occurrence at the Presidio in San Francisco; plants there belong to a single clone. Five of six historical occurrences extirpated by urbanization; currently threatened by non-native plants, encroachment of native shrubs, and branch dieback due to fungal pathogen. USFWS uses the name A. pungens var. ravenii. See Madroño 19(6):200 (1968) 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 5 February 2025].