Synonyms: W. filamentosa (often mistaken for native W. filifera)
Common names: Mexican fan palm; Washington palm; skyduster; thread palm
Washingtonia robusta (Mexican fan palm) is a single-trunked palm tree (family Arecaceae) found in the San Francisco Bay area, southern Sacramento Valley and on California’s south coast. Mexican fan palm is a common landscape ornamental that has become invasive in riparian areas, orchards and landscaped areas. This palm is known to create monospecific stands in riparian areas, and dead fronds of the tree can create a fire hazard. The species can be controlled with relative ease by removing the seedlings.Cal-IPC Rating: Moderate — Alert
Plant Assessment Form - Information gathered by Cal-IPC on the impacts, rate of spread, and distribution of invasive plants in California. Does not include management information.
Weed RIC Management Notes
- Management Notes - Information on management techniques and effectiveness from the University of California Cooperative Extension’s Weed Research & Information Center.
Cal-IPC Newsletter Articles
- Lessons learned from a 12-year eradication program targeting 34 species. Knapp, John. Vol 27, Issue 1
- Which weeds dominate southern California urban riparian systems?. Burkhart, Brad; Kelly, Mike. Vol 13, Issue 1
- Education: Wildland weed tours and talks. Kelly, Mike. Vol 08, Issue 1
- Roundup of Arundo projects reveals commitment, strategic weakness. Kelly, Mike. Vol 07, Issue 2
Cal-IPC Symposium Presentations
Presentations are linked where available. Where a presentation is not available, find more information by reading the abstract in the Cal-IPC Symposia Archive.
- 2003 Cal-IPC red alert! New invasions, recent expansions, and a few others to be on the look-out For…. Tu, Mandy; Randall, John M. (2003)
- 2002 Red alert! New introductions and recent expansions in California. Tu, Mandy; Randall, John M. (2002)
Other Washingtonia robusta Information
- CalPhotos - Images of plants taken mostly in California.
- Calflora - See the distribution of this species on Calflora's map of California.
- CalWeedMapper - Distribution information with ability to determine regional priorities.
- Jepson Online Interchange for California Flora - Information on taxonomy, biology, and distribution from UC Berkeley's Jepson Herbarium.
- USDA PLANTS Database - Federal database with information on identification and distribution, and links to websites in individual states.