This hanging white trap you have scanned is for control of South American palm weevil, an invasive pest that has killed thousands of palms in San Diego County. UC Riverside is concuding an expirment to try and control the weevil population that is killing the palm trees in the greater Rancho Santa Fe area.
Weevils are attracted to the pheromone, a weevil specific odor that weevils find irresistible in the capsule hanging from the roof of the trap. Below the capsule is a small dollop of grey waxy material that holds a very low concentration (3-5%) of a contact insecticide, cypermethrin (rated warning, MSDS sheet is available here). When weevils are attracted to the pheromone they touch the dollop and they die.
This Attract and kill method has the potential to provide control of weevils over very large areas with massive reductions in insecticide applications.
In March 2024, inside the Rancho Santa Fe Community 1,710 traps were hung for weevil control. Fairbanks Ranch and the Del Mar Country HOAs are also participating in this weevil management program.
Frequently Asked Questions
Can I touch, remove, or alter the traps?
Please don’t move, touch, or remove the traps. Traps have been placed in specific locations and precisely calculated numbers have been deployed in specific areas so we can measure the impacts of attract and kill on weevil populations as a function of trap density.
What do I do if I find a trap on the ground?
If you find a trap on the ground please contact Maryam Babaki Rancho Santa Fe Planning & Development Director (Phone: 858-756-1174; email: maryam@rsfassociation.org) or Danny Lines, Rancho Santa Fe Infrastructure Manager (email: danny@rsfassociation.org).
Has the Rancho Santa Fe HOA given permission for this project?
Yes, the Rancho Santa Fe HOA board strongly supports this weevil control program.
Has the County of San Diego given permission for this project?
Yes, the County of San Diego is very supportive of this project. The project has been inspected in Rancho Santa Fe by authorized County Personnel for compliance and the project has been certified as being in compliance.
When will we know if the project has been successful for control palm weevils?
The project will be running for at least one year. Traps will be replenished with pheromone and insecticide in June 2024. Each month, traps that catch live weevil in the Rancho Santa Fe community are inspected for weevils. We hope to see a decrease in the number of live weevils trapped each month. However, we are not sure how long this will take to observe.
For more information about the weevil
UCR's general information page about the South American palm weevil https://biocontrol.ucr.edu/south-american-palm-weevil
UCR podcast episode about the South American Palm Weevil history and current research https://podcasters.spotify.com/pod/show/can-i-bug-you/episodes/Ep--1-Palm-Weevils-e2fjf8e/a-aaus4t8
YouTube Video on the Palm Weevil
https://youtu.be/S6a3Q5DzeBM?si=V0L02qF42UAzcEeV