Calflora: Silybum marianum

Silybum marianum (L.) Gaertn.

blessed milkthistle, milk thistle, milkthistle

Silybum marianum, a dicot, is an annual or perennial herb that is not native to California; it was introduced from elsewhere and naturalized in the wild.

The California Invasive Plant Council (Cal-IPC) classifies the potential impact of Silybum marianum on native ecosystems as limited (plant profile).

Communities:	weed, species characteristic of disturbed places
Habitat:	disturbed [Walker]
Elevation:	between 0 and 1640 feet
Family:	ASTERACEAE

Name Status:

Accepted by TJM2 + PLANTS + JM93

Other Names:

PLANTS:	Carduus marianus
PLANTS:	Mariana mariana

Plant
Characteristics
+ Associated
Organisms

Bloom Period

Add an
Observation

Observation Hotline
including observations with photos

Distribution by County:

See a detailed Distribution Grid of this plant in California.

A shaded county indicates that there are ocurrence records of this plant within the county.

Hover the mouse over the map to see county names. Click to view records from that county.

	There are specimen records from this county in an herbarium.
	There are documented records, vouchered or confirmed by an expert.
	There are reported records.
	There are reported records available indirectly (eg. in botanical literature).

Records by County, with approximate record counts in the form: TOTAL / CCH. Click county name to view records.

Alameda: 280 / 4 CCH Amador: 1 / 0 CCH Butte: 66 / 13 CCH Contra Costa: 24 / 5 CCH Colusa: 2 / 1 CCH Del Norte: 2 / 0 CCH El Dorado: 4 / 1 CCH Fresno: 7 / 1 CCH Glenn: 3 / 0 CCH Humboldt: 8 / 5 CCH Kern: 603 / 1 CCH Los Angeles: 668 / 41 CCH Madera: 1 / 0 CCH Mendocino: 23 / 2 CCH Merced: 18 / 1 CCH Monterey: 54 / 7 CCH Mariposa: 2 / 0 CCH Marin: 92 / 2 CCH Napa: 11 / 2 CCH Nevada: 3 / 0 CCH Orange: 55 / 15 CCH Placer: 3 / 0 CCH Riverside: 26 / 13 CCH Sacramento: 15 / 2 CCH Santa Barbara: 75 / 60 CCH San Bernardino: 50 / 15 CCH San Benito: 4 / 0 CCH Santa Clara: 87 / 6 CCH Santa Cruz: 6 / 1 CCH San Diego: 88 / 53 CCH San Francisco: 27 / 1 CCH Shasta: 5 / 0 CCH San Joaquin: 3 / 0 CCH San Luis Obispo: 21 / 10 CCH San Mateo: 72 / 1 CCH Solano: 13 / 2 CCH Sonoma: 43 / 2 CCH Stanislaus: 18 / 1 CCH Sutter: 5 / 2 CCH Tehama: 6 / 4 CCH Tulare: 16 / 1 CCH Tuolumne: 3 / 0 CCH Ventura: 31 / 13 CCH Yolo: 8 / 5 CCH

CCH: records provided by the participants of the Consortium of California Herbaria.

Information about Silybum marianum from other sources:

Photos on Picasa / Flickr / Google Images
website references on Google
USDA PLANTS Profile (SIMA3)

2012 Jepson Manual Treament from the Jepson Herbarium,
University of California, Berkeley
Original Publication citation. on the International Plants Names Index
Search efloras.org (Flora of North America)
Search the Lady Bird Johnson Wildflower Center Native Plant Database