Taxon Report

Ceanothus confusus J.T. Howell

Rincon Ridge ceanothus

Print Report


© 2012 Jake Ruygt

  Classification
Scientific Name:
 Ceanothus confusus J.T. Howell
Common Name:
 Rincon Ridge ceanothus
Family: Rhamnaceae
Element Code: PDRHA04220
USDA Plants Symbol: CECO6
Synonyms/Other Names:

Ecology and Life History
Lifeform: perennial evergreen shrub
Blooming Period: Feb-Jun Feb-Jun
Elevation: 75-1065 (245-3495)
General Habitats: Chaparral, Cismontane woodland, Closed-cone coniferous forest
Microhabitat: Serpentine (sometimes), Volcanic (sometimes)
Microhabitat Details:

Conservation Status
CA Rare Plant Rank: 1B.1
Global Rank: G1
State Rank:
 S1
State List: None
Fed List: None
Other Status: BLM_S; SB_SBBG
CRPR Changes:

Occurrence Data from the CNDDB
Total Occurrences: 33
Element Occurrence Ranks:
   Excellent (A) 1
   Good (B) 2
   Fair (C) 5
   Poor (D) 0
   None (X) 1
   Unknown (U) 24

Location
California Endemic:  True
California Counties and Islands: Name (Code)
Lake (LAK), Mendocino (MEN), Napa (NAP), Sonoma (SON)
Quads: Name (Quad Code)
Bartlett Mtn. (3912227), Calistoga (3812255)?*, Camp Meeker (3812248), Cloverdale (3812371), Detert Reservoir (3812265), Geyserville (3812268), Guerneville (3812258), Kenwood (3812245), Mark West Springs (3812256), Mount St. Helena (3812266), Purdys Gardens (3912311), Rutherford (3812244), Santa Rosa (3812246), Sebastopol (3812247)*, Sonoma (3812234), St. Helena (3812254), The Geysers (3812277), Whispering Pines (3812276), Yorkville (3812382)

Threat List Data from the CNDDB

Threat List Total: 9
EOs with Threat Listed: Total EOs % of EOs
12 36 %
Development 8 24%
Road/trail construction/maint. 8 24%
Agriculture 4 12%
ORV activity 3 9%
Other 1 3%
Recreational use (non-ORV) 1 3%
Grazing 1 3%
Logging 1 3%
Wood cutting or brush clearing 1 3%

Notes
Closely related to C. prostratus. See Leaflets of Western Botany 2:160-162 (1939) for original description.
Threats:
Threatened by development. 
Taxonomy:

Selected References

Profile for potential SCC evaluation (2018)
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 January 2025].