Taxon  Report   2118 
Cirsium arvense  (L.) Scop.
Canada thistle

Cirsium arvense
© 2007 Luigi Rignanese
Cirsium arvense
© 2009 Phil Pullen
Cirsium arvense, a dicot, is a perennial herb that is not native to California; it was introduced from elsewhere and naturalized in the wild.
The California Invasive Plant Council classifies its potential impact on native ecosystems as moderate   (plant profile / CalWeedMapper).

 Interactive Distribution Map 

 Observation Hotline 
 (observation details + photos)

point, line, or polygon

one or more occurrences within a 7.5-minute quadrangle

 Plant Characteristics
 and Associations

Bloom Period
Cirsium arvense
© 2008 Keir Morse
Genus: Cirsium
Wetlands:Equally likely to occur in wetlands or non wetlands [U.S. Fish & Wildlife Service.]
Distribution by County 

Add an Observation of  Cirsium arvense

Name Status:
Accepted by TJM2 + PLANTS + JM93
Alternate Names:
(according to)

PLANTS: Breea arvensis
PLANTS: Cirsium setosum
PLANTS: Cirsium incanum
PLANTS: Cirsium arvense var. vestitum
PLANTS: Cirsium arvense var. mite
PLANTS: Cirsium arvense var. integrifolium
PLANTS: Cirsium arvense var. horridum
PLANTS: Cirsium arvense var. argenteum
PLANTS: Carduus arvensis
PLANTS: Breea incana
PLANTS: Serratula arvensis
 More information about  Cirsium arvense

Photos on CalPhotos / Google Images

website references on Google

UC Integrated Pest Management Weed Photo Gallery
(profile of this plant as an agricultural weed)

Jepson eFlora

Records from the Consortium of California Herbaria

Original Publication citation. on the
International Plants Names Index

Search (Flora of North America)

Suggested Citation
Calflora: Information on California plants for education, research and conservation,
with data contributed by public and private institutions and individuals, including the Consortium of California Herbaria.
[web application]. 2015. Berkeley, California: The Calflora Database [a non-profit organization].
Available:   (Accessed: Nov 29, 2015).

The information on this page comes from diverse sources. None of the links are sponsored.

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