San Diego County is telling anyone who picked up a desert willow at Costco between June 24 and July 3 to hit pause on their gardening plans. County agriculture officials say the popular trees may be crawling with glassy‑winged sharpshooters, an invasive insect that can quietly hitch a ride into local yards and eventually hammer vineyards and backyard gardens.
Instead of hauling the plant back to the store or tossing it in green waste, residents are being urged to isolate it and call county inspectors. The warning comes on the heels of broader state and regional detections of the glassy‑winged sharpshooter, a notorious vector of Pierce’s disease in grapevines.
What Officials Found and Why It Matters
State and county inspectors have confirmed that glassy‑winged sharpshooters were riding along on desert willows sold at select Costco warehouses, according to the Los Angeles Times. The same pest was detected on grapevines earlier this spring, triggering a multi‑county effort to track down and remove infested plants.
Officials warn that the sharpshooter can spread the bacteria responsible for Pierce’s disease, a grapevine killer that can wipe out commercial vineyards and damage home plantings. In other words, a seemingly harmless big‑box store tree can turn into a serious problem for California wine country and neighborhood gardens alike.
How to Handle Suspect Plants
For anyone who brought one of these trees home, the instructions are specific and a bit fussy, but there is a reason for the caution. Authorities say to keep the plant in its original pot, park it away from other plants, and do not plant it, move it around town, or dump it in green waste.
If the desert willow is still in a container, the California Department of Food and Agriculture advises sealing it inside two plastic bags and putting it in the regular trash so it will not be mulched and spread. If the tree is already in the ground, an agricultural inspector will come out, check it, and if needed remove and dispose of it safely.
As part of the broader response, state and county crews are setting traps around stores and neighborhoods and removing targeted infested plants to keep the pest from gaining a stronger foothold.
Where the Plants Came From and the Ongoing Response
The desert willows in the latest round of concern trace back to a nursery in Tyler, Texas. State officials estimate that hundreds of plants linked to that shipment were sold across California, which is why customers around the state are now hearing from agriculture departments and Costco.
County agricultural offices are working directly with the retailer to identify, inspect and pull any infested stock from store shelves, while also trying to track down trees already sold to residents. In some counties, inspectors have already located and destroyed most of the suspect plants. Elsewhere, teams are still setting traps and knocking on doors in neighborhoods where deliveries were made.
Other Sharpshooters and the Risk to Vineyards
State pest profiles note that another potential vector, the broad‑headed sharpshooter, is not known to be established in California, though officials are keeping an eye out for any interceptions or detections, according to CDFA.
The UC IPM program notes that the glassy‑winged sharpshooter is an especially efficient carrier of the bacteria that cause Pierce’s disease. Outbreaks can be devastating for vineyards, which is why officials treat any new finds as urgent business. County and state teams say rapid detection and removal are key to limiting the spread and preventing long‑term damage.
Local Help and Who to Call
San Diego County’s Department of Agriculture, Weights & Measures lists two main numbers for residents who think they may have one of the suspect trees: the San Diego office at 858‑694‑2739 and the San Marcos office at 760‑752‑4700. The department also takes questions by email at [email protected].
The alert was shared on the county’s official social media channels, and officials say they are working closely with state regulators and Costco, which is reaching out to customers and cooperating with the response, according to the County of San Diego. Anyone unsure about a recent plant purchase is urged to contact their local agricultural office rather than moving or disposing of the plant on their own.
Bought a desert willow plant at Costco 6/24 – 7/3? 🚨
— SanDiegoCounty (@SanDiegoCounty) July 20, 2026
The glassy-winged sharpshooter pest has been found on these plants in California. Threatens vineyards & backyard gardens.
Act now & see details: https://t.co/TV8t5euYiG pic.twitter.com/4jojy720xe
