Calflora
Taxon  Report   2118    
Cirsium arvense  (L.) Scop.
Canada thistle
Cirsium arvense
© 2008 Keir Morse
Photos from
CalPhotos / Calflora
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. Cal-IPC rating: Moderate

Interactive Distribution Map


Observation Hotline
(observation details)



point, line, or polygon

one or more occurrences
within a 7.5-minute quadrangle

Plant Characteristics
and Associations



Bloom Period
Cirsium arvense
© 2018 Joel Trumbo
Family: ASTERACEAE  
Genus: Cirsium
Communities: wetland-riparian

Wetlands:
Arid West: Occurs usually in non wetlands, occasionally in wetlands
Mountains, Valleys and Coast: Equally likely to occur in wetlands and non wetlands

Name Status:
Accepted by JEF + PLANTS

Alternate Names:
PLANTS: Breea arvensis
PLANTS: Cirsium setosum
PLANTS: Cirsium incanum
. . .
More information about  Cirsium arvense
Photos on PlantID.net   /   Google Images
UC Integrated Pest Management Weed Photo Gallery
(profile of this plant as an agricultural weed)

Jepson eFlora

Records from the Consortium of California Herbaria

ITIS Original Publication citation

USDA PLANTS Profile (CIAR4)

Search the International Plants Names Index

Search efloras.org (Flora of North America)

website references from Google


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]. 2018. Berkeley, California: The Calflora Database [a non-profit organization]. Available: https://www.calflora.org/   (Accessed: Dec 16, 2018).