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Taxon  Report  
Cirsium hydrophilum  (Greene) Jeps.  var. vaseyi  (A. Gray) J. T. Howell
Mt. Tamalpais thistle,   Vasey's thistle
Cirsium hydrophilum var. vaseyi 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).
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
(49 records)
yellowone or more occurrences
within a 7.5-minute quadrangle
bloom graphic
Bloom Period
Parent: Cirsium hydrophilum
Genus: Cirsium
Family: Asteraceae  
Category: angiosperm  
PLANTS group:Dicot
Jepson eFlora section: eudicot

Wetlands: Occurs in wetlands

Ultramafic affinity: 6 - strict endemic

Habitat: seeps

Communities: Mixed Evergreen Forest, Chaparral, wetland-riparian

Name Status:
Accepted by JEF + CNPS + PLANTS
Alternate Names:
PLANTSCirsium montigenum
PLANTSCirsium vaseyi
PLANTSCnicus breweri var. vaseyi
Information about  Cirsium hydrophilum var. vaseyi from other sources
Nursery availability from CNPLX
Commercial availability unknown.
Jepson eFlora

USDA PLANTS Profile (CIHYV)

Photos on Calflora

Photos on CalPhotos

Google Images

Photos on iNaturalist

ID Tips on PlantID.net


Suggested Citation
Calflora: Information on California plants for education, research and conservation, with data contributed by public and private institutions and individuals. [web application]. 2023. Berkeley, California: The Calflora Database [a non-profit organization]. Available: https://www.calflora.org/   (Accessed: 05/30/2023).