Synonyms: Hypericum floribundum
Common names: Canary Island St. Johnswort; Grenadillo
Hypericum canariense (Canary Island hypericum) is a rhizomatous perennial shrub (family Clusiaceae) found on the central and south coast of California and in the southern San Francisco Bay region. Canary Island hypericum infests disturbed areas, especially in coastal sage scrub and grassland habitats. This ornamental shrub forms dense stands that exclude native species. It is not yet widespread, but its prolific seed production makes rapid spread possible.Rating: Moderate
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- Dlugosch, K. (2002). Recently-introduced shrub Hypericum canariense (Canary Island St. Johnswort). California Exotic Pest Plant Council Symposium 2002. Sacramento, CA.
- Tu, M. and J. M. Randall (2002). 2002 Red alert! New introductions and recent expansions in California. California Exotic Pest Plant Council Symposium 2002. Sacramento, CA.
- Tu, M. and J. M. Randall (2003). 2003 Cal-IPC red alert! New invasions, recent expansions, and a few others to be on the look-out For. California Invasive Plant Council Symposium 2003. Kings Beach, CA.
Cal-IPC News Articles
- Dlugosch, K. (2002). Recently-introduced shrub Hypericum canariense (Canary Island St. Johnswort).
- Tu, M. (2001). Red alert! Hypericum canariense L. (Canary Island St. Johnswort). CalEPPC News. 9: 6,10.
- Tu, M. (2002). Hypericum canariense. CalEPPC News. 10: 10.
- Tu, M. and J. M. Randall (2002). 2002 Red Alert! New introductions and recent expansions in California.
- Tu, M. and J. M. Randall (2003). 2002 REd Alert! New introductions and recent expansions in California.