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Taxon  Report  
Cirsium rhothophilum  S. F. Blake
Surf thistle
Cirsium rhothophilum is a perennial herb that is native to California, and endemic (limited) to California.
California Rare Plant Rank: 1B.2 (rare, threatened, or endangered in CA and elsewhere).
State of California status: Threatened.
Siskiyou Del Norte Modoc Humboldt Shasta Lassen Trinity Plumas Tehama Butte Mendocino Glenn Sierra Yuba Lake Nevada Colusa Placer Sutter El Dorado Yolo Alpine Napa Sonoma Sacramento Mono Amador Solano Calaveras Tuolumne San Joaquin Marin Contra Costa Alameda Santa Cruz Mariposa Madera San Francisco San Mateo Merced Fresno Stanislaus Santa Clara Inyo San Benito Tulare Kings Monterey San Bernardino San Luis Obispo Kern Santa Barbara Ventura Los Angeles Riverside Orange San Diego Imperial
Observation Search
~55 records in California
yellowone or more occurrences
within a 7.5-minute quadrangle
DJJJASONAFMM

Bloom Period
Genus: Cirsium
Family: Asteraceae  
Category: angiosperm  
PLANTS group:Dicot
Jepson eFlora section: eudicot

Habitat: dunes, coastal

Communities: Coastal Strand, Coastal Sage Scrub

Name Status:
Accepted by JEF + CNPS + PLANTS + POWO
Alternate Names:
PLANTSCirsium maritimum
Information about  Cirsium rhothophilum from other sources
Nursery availability from CNPLX
Commercial availability unknown.
Jepson eFlora

USDA PLANTS Profile (CIRH)

Photos on Calflora

Photos on CalPhotos

Google Images

Photos on iNaturalist

ID Tips on PlantID.net

[Wikipedia] Range, Habitat: Cirsium rhothophilum is a rare North American species of thistle known by the common name surf thistle. It is endemic to California, where it is known only from the coastline around the border between San Luis Obispo and Santa Barbara Counties. It grows in sand dunes and coastal scrub near the beach. (link added by Mary Ann Machi)


Suggested Citation
Calflora: Information on California plants for education, research and conservation, with data contributed by public and private institutions and individuals. [web application]. 2024. Berkeley, California: The Calflora Database [a non-profit organization]. Available: https://www.calflora.org/   (Accessed: 12/20/2024).