logo Calflora, a 501c3 non-profit
Taxon  Report  
Silybum marianum  (L.) Gaertn.
Blessed milkthistle,   Milk thistle
Silybum marianum is an annual or perennial herb that is not native to California.
Cal-IPC rating: limited
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
~6809 records in California
redone or more occurrences
within a 7.5-minute quadrangle
DJJJASONAFMM

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

Habitat: disturbed

Communities: weed, characteristic of disturbed places

Name Status:
Accepted by JEF + PLANTS

Alternate Names:
PLANTSCarduus marianus
PLANTSMariana mariana
Information about  Silybum marianum from other sources

[Wikipedia] Europe, Asia, India, Africa native; Invasiveness: Silybum marianum is a species of thistle. It has various common names including milk thistle, blessed milkthistle, Marian thistle, Mary thistle, Saint Mary's thistle, Mediterranean milk thistle, variegated thistle and Scotch thistle (though not to be confused with Onopordum acanthium or Cirsium vulgare). Originally a native of Southern Europe through to Asia, it is now found throughout the world. Silybum marianum establishes itself in sunny, warm ruderal meadows in regularly disturbed places such as rubble deposits, at the foot of south-exposed walls or villages and on urban fallow land or on cattle pastures. However, it does not prefer dry, stony soils. Milk thistle has been potentially observed to modify fire regimes in its invasive range.Its invasion into new habitats may also be encouraged by fire. (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: 07/18/2024).