Taxon Report

Ceanothus gloriosus J.T. Howell var. porrectus J.T. Howell

Mt. Vision ceanothus

Print Report


Taxon Summary

Ceanothus gloriosus var. porrectus, commonly known as Mt. Vision ceanothus, is a perennial evergreen shrub in the Rhamnaceae that is found only in California. It occurs within Closed-cone coniferous forest, Coastal prairie, Coastal scrub, and Valley and foothill grassland, growing at elevations from 25 to 305 meters. Ceanothus gloriosus var. porrectus is ranked 1B.3, Plants Rare, Threatened or Endangered in California and Elsewhere; Not very threatened in California.


  Classification

Scientific Name:
Ceanothus gloriosus J.T. Howell var. porrectus J.T. Howell
Common Name:
Mt. Vision ceanothus
Family: Rhamnaceae
Element Code: PDRHA040F7
USDA Plants Symbol: CEGLP
Synonyms/Other Names:

Ecology and Life History

Lifeform: perennial evergreen shrub
Blooming Period: Feb-May Feb-May
Elevation: 25-305 (80-1000)
General Habitats: Closed-cone coniferous forest, Coastal prairie, Coastal scrub, Valley and foothill grassland
Microhabitat:
Microhabitat Details:

Occurrence Data from the CNDDB

Total Occurrences: 18
Element Occurrence Ranks:
   Excellent (A) 1
   Good (B) 10
   Fair (C) 2
   Poor (D) 0
   None (X) 0
   Unknown (U) 5
California Endemic:  True
California Counties and Islands: Name (Code)
Marin (MRN)
Quads: Name (Quad Code)
Drakes Bay (3812218), Inverness (3812217), Tomales (3812228)

Threat List Data from the CNDDB

Threat List Total: 8
EOs with Threat Listed: Total EOs % of EOs
13 72 %
Other 8 44%
Grazing 7 38%
Foot traffic/trampling 3 16%
Road/trail construction/maint. 2 11%
Vandalism/dumping/litter 1 5%
Erosion/runoff 1 5%
Mining 1 5%
Non-native plant impacts 1 5%

Notes

Known from fewer than 20 occurrences in the Mt. Vision area near Pt. Reyes. Some plants destroyed by quarrying; occurs in areas grazed by cattle. Possibly threatened by competition. Can intergrade with Ceanothus gloriosus var. gloriosus.
Threats:
Taxonomy:
Citation California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 12 February 2025].