Calflora
Taxon  Report   1853    
Centaurea solstitialis  L.
Barnaby's thistle,  Yellow star thistle
Centaurea solstitialis, a dicot, is an annual herb that is not native to California; it was introduced from elsewhere and naturalized in the wild. Cal-IPC rating: High
Observation Hotline
(observation details)
one or more occurrences
within a 7.5-minute quadrangle

Bloom Period
Family: ASTERACEAE  
Genus: Centaurea
Habitat: disturbed

Communities: weed, characteristic of disturbed places

Name Status:
Accepted by ICPN + PLANTS

Alternate Names:
PLANTS: Leucantha solstitialis
More information about  Centaurea solstitialis

FEIS: DISTRIBUTION AND OCCURRENCE:  "It is likely that there were multiple introductions of yellow starthistle to the United States ... and that contaminated alfalfa seed (Medicago sativa) was the primary vehicle for these introductions ... . Yellow starthistle seeds were found in adobe bricks from the period between 1824 and 1848 in California (Hendry 1931, ...). The plant was first collected in Oakland, California in 1869 and was most likely introduced from Chile, while introductions from 1899 to 1927 appear to be from Turkestan, Argentina, Italy, France and Spain "

UC Integrated Pest Management:  ... It forms dense infestations and rapidly depletes soil moisture, thus preventing the establishment of other species. It is also poisonous to horses, causing a nervous disorder called “chewing disease” ...


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]. 2019. Berkeley, California: The Calflora Database [a non-profit organization]. Available: https://www.calflora.org/   (Accessed: Aug 17, 2019).