Calflora, a 501c3 non-profit
Taxon  Report  
Cirsium arvense  (L.) Scop.
Canada thistle
Cirsium arvense is a perennial herb that is not native to California.
Cal-IPC rating: Moderate
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Observation Search
(3019 records)
one or more occurrences
within a 7.5-minute quadrangle

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

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

Communities: wetland-riparian

Name Status:
Accepted by JEF + PLANTS
Alternate Names:
PLANTSBreea arvensis
PLANTSBreea incana
PLANTSCarduus arvensis
PLANTSCirsium arvense var. argenteum
PLANTSCirsium arvense var. horridum
...
More information about  Cirsium arvense

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]. 2022. Berkeley, California: The Calflora Database [a non-profit organization]. Available: https://www.calflora.org/   (Accessed: 09/26/2022).