CDFA is urging consumers to report grapevines purchased from Northern California Costco stores after glassy-winged sharpshooters were found on nursery stock shipped from a Fresno nursery, triggering a statewide containment response aimed at protecting winegrape regions from Pierce’s disease.
The first pest was detected May 19 on grapevine stock at a Costco in Sonoma, CDFA Undersecretary Christine Birdsong told the State Board of Food and Agriculture last week. County agricultural commissioners immediately began tracing the shipment backward and forward to determine where the vines came from and where they had been distributed, she explained.
CDFA says about 13,000 vines were shipped to Costco stores between April 21 and May 21. The department is asking anyone who bought grapevines from a Northern California Costco store during that period to contact their local agricultural commissioner and keep the plants isolated.
Birdsong said the vines came from Fresno-based Burchell Nursery, near an area infested with glassy-winged sharpshooter. She said the nursery was not following its compliance agreement, did not tag the grapevine stock, and did not provide advance notification to receiving counties. Those protocols are meant to alert counties and retailers that stock from a higher-risk area requires additional inspection.
As of Birdsong’s update, 12 counties had confirmed glassy-winged sharpshooter findings on nursery stock at Costco stores, with six more counties awaiting confirmation. CDFA said in its Friday statement that it is working with county agricultural commissioners to locate vines sold to consumers across 24 counties, as well as nearby at-risk counties.
Birdsong said infested stock and nearby plants at Costco stores have been destroyed. No additional sharpshooters were found on other nearby nursery plants, she said. CDFA and counties are also responding to public reports, inspecting vines, conducting outreach, and placing traps near stores and locations where purchased vines were taken.
“This isn’t just an ag vineyard problem,” said Birdsong. “This is now a consumer issue.”
CDFA said Costco is offering full refunds and customers do not need to return the vines. Instead, the department is asking customers to keep plants in their original containers, away from other plants, double bag them if possible, and avoid placing them in trash or compost bins. Agricultural inspectors will inspect and, if necessary, remove and dispose of the plants.
Birdsong said the state expects three years of continuous monitoring because an infestation may take that long to become large enough to detect. She also said Reps. Jim Costa, David Valadao and Mike Thompson have submitted an appropriations amendment seeking additional funding for California’s response.
The pest threatens winegrapes by spreading Pierce’s disease, which can kill vines. A CDFA economic study last year estimated the disease could cost California about $166 million annually if left unchecked.
