Earlier this month I reported on the discovery in Laguna Beach of the world's most destructive pest of palms, the Red Palm Weevil.
In the past three weeks this 1.5 inch beetle has caused a flurry of activity among county, state and federal officials. Local palm enthusiasts have begun to panic and landscape professionals, responsible for the health of the regions palms, are worried.
If this exotic pest establishes itself in California, the damage to date palms, both in landscapes and agriculturally, would likely be catastrophic. Already, in southern Europe, in only a few years, over 100,000 Phoenix date palms have been destroyed, many more are doomed and the equivalent of more than 140 million Euros have been spent with almost no effect.
To recap, the Red Palm Weevil was first detected in The U.S. in the Emerald Bay neighborhood of northern Laguna Beach in late September of this year. The pests were discovered by arborists during the removal of a mature, dying Canary Island Date Palm.
Monitoring for additional Red Palm Weevils began soon after this initial discovery. Don Hodel, an Environmental Horticulturist with The University of California Cooperative Extension and considered one of the country's leading palm specialists and Nick Nisson, Orange County's entomologist, conducted a visual survey in the area, but were unable to locate any additional pests.
About 250 traps, specially designed to attract and retain adult Red Palm Weevils have been placed by California Department of Food and Agriculture staff throughout a nine square mile area surrounding the initial discovery. In addition, extensive door to door surveys are being performed by a team of CDFA inspectors. Thus far, the surveyors have inspected 86% of the properties in a 1.5 square mile area around the "hot zone." 1,481 properties and 9,721 palms have been surveyed.
Through Monday, no additional Red Palm Weevils had been seen or captured in the extensive network of traps.
But bad news arrived via my email in-box at 7 PM on Tuesday from Dr. Mark Hoddle, director of invasive pest studies at UC Riverside's Center For Invasive Species Research. Another dying Canary Island Date Palm was discovered just blocks from the initial infestation.
This second infested Laguna Beach palm was heavily damaged and near death. Dr. Hoddle reports, "The crown of the palm has dropped off and the top of the trunk is now ringed with a "halo" of palm fronds. The trunk of the palm has been heavily damaged internally by feeding Red Palm Weevils. The central portion of the trunk now contains a highly fermented and very wet "mash" of plant material."
Portions of at least nine dead adult weevils, one live adult and seven empty pupal cases were discovered at the site of the dying tree, which to-date has still not been removed. Additional weevils may still be present within the dying tree.
It is now likely that additional palms in the area of North Laguna are infested with this destructive pest.
County, state and federal officials are working swiftly to assemble strategies to deal with this pest. An informational meeting has been called for next week in Laguna Beach to inform local government officials, arborists, public works, landscapers, and pest control advisors about the current Red Palm Beetle situation, including properly identifying the pest and its feeding damage. Future meetings will target other groups, including the public. I will keep you posted.
In the meantime, what can you do? First, learn more about this pest, so that misinformation is not spread and improper reactions do not ensue. Dr. Hoddle and his colleagues have created an excellent website and blog with updates at http://cisr.ucr.edu/red_palm_weevil.html. Also visit www.cdfa.ca.gov/phpps/rpw/ for additional information and photos.
Second, after learning to recognize at least the advanced symptoms of palms infested with Red Palm Weevils, report any suspicious plants, along with details to CDFA's pest hotline at 800-491-1899.
If government experts, local communities, landscape professionals and concerned citizens work together, in an integrated manner, we may be able to eradicate this destructive pest before it advances further. Working together and intelligently, we may be able to save California's majestic and iconic date palms.
Ron Vanderhoff is the Nursery Manager at Roger’s Gardens, Corona del Mar.