City moves forward with phased plan to protect palms from invasive weevil

By CLARA BEARD

Dana Point is moving ahead with a phased plan to protect its Canary Island date palms from an invasive beetle that has already been detected in the city, though City Council members want more community feedback before committing to the program’s growing long-term costs.

The City Council on Tuesday (Sept. 1) approved a framework that prioritizes 331 city-maintained Canary Island date palms for preventive treatment against the South American palm weevil, an invasive pest that can kill palms once larvae burrow into the tree’s crown.

The city has already begun the first phase of treatment, covering 98 heritage palms along Camino Capistrano and Avenida Las Palmas in Capistrano Beach. Council members previously approved that work in July at an annual cost of about $68,745.

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Photo by Clara Beard

Dana Point is moving forward with a phased treatment plan to protect city-maintained Canary Island date palms

Tuesday’s action lays out three additional phases that could eventually expand treatment to all 331 city-maintained palms.

Phase two would bring the total number of treated palms to 166 at an estimated annual cost of $116,994. Phase three would cover 248 palms for about $173,087 per year, while treating all 331 palms under phase four would cost approximately $227,314 annually.

Rather than immediately committing to each phase, the council directed staff to move toward phase two as the threat warrants and return through the city’s annual budget process for funding. Council members also requested outreach to determine how strongly residents value preserving the palms before making further spending decisions.

Mayor Pro Tem Mike Frost urged the city to slow down before making a larger financial commitment, asking where palm preservation ranks among residents’ priorities.

“I would just like to pump the brakes for a little bit,” Frost said during the discussion.

Assistant City Manager Jeff Rosaler said the South American palm weevil has now been confirmed at the Dana Point Nature Interpretive Center and Sunset Park. The pest has spread north from San Diego County over the past decade, with University of California researchers estimating it has killed more than 20,000 palms across Southern California.

The Canary Island date palm is particularly vulnerable. Female weevils lay eggs in the crown, where larvae bore inward and destroy the palm’s single growing point. Because much of that damage occurs internally, an infestation can go unnoticed until the crown begins collapsing. By that point, according to the staff report, the tree cannot be saved and can become a source of additional weevils.

For palms not yet receiving preventive treatment, the city plans to use inspections and pheromone-baited traps to monitor for weevil activity. If activity is found near a city palm, staff would inspect the tree and either treat it or remove it if it is too heavily damaged. An optional citywide trap network is estimated to cost about $6,780 annually.

Staff developed a scoring system to determine which palms receive treatment first. Trees are ranked based on their historic or community significance, size and age, visibility, potential public safety risk and proximity to confirmed weevil activity.

The council discussion also focused heavily on whether continually treating the trees is more cost-effective than eventually removing and replacing them.

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Council members questioned staff about the cost of losing the palms and whether another species could be planted instead. The discussion included estimates of roughly $2,500 to remove an individual palm, while replacement costs could be significantly higher depending on the size of the new tree. Some council members also raised the possibility that replacing the palms with a species less susceptible to the weevil could eventually prove less expensive than maintaining an indefinite treatment program.

The city’s staff report, however, recommends preventive treatment, saying there is no cure once the palm’s growing point has been destroyed.

The council ultimately agreed to retain the phased approach while adding community outreach to the process. Staff will return with the results when requesting funding to advance into phase two.

The treatment program applies only to palms owned or maintained by the city. Palms on private property remain the responsibility of property owners, though the city plans to provide education and outreach about the pest.