Invasive Sharpshooter Found on Costco Plants

The California Department of Food and Agriculture said on May 29 that invasive glassy-winged sharpshooters had been found on grapevine shipments sold at select Costco locations in California between April 21 and May 21. Santa Clara County issued its own recall alert a day earlier, telling residents who bought affected grapevines between April 21 and May 19 to contact the county’s Division of Agriculture immediately. The insect is a known vector of Pierce’s disease, a bacterial infection that kills grapevines and can also damage citrus trees, landscape plants and other crops. State and county officials said the immediate goal is to find plants that may already be in backyards and keep the pest from spreading farther in Northern California. ### Which Costco plants are part of the alert? CDFA said the response centers on grapevines sold at select Costco locations in affected counties during the April 21-to-May 21 window. Santa Clara County’s notice used a slightly earlier end date — May 19 — and said the county was included among the affected areas. San Mateo County said Bay Area residents who purchased grape plants from Costco stores beginning April 21 should take immediate precautions. (cdfa.ca.gov) San Mateo County Agricultural Commissioner Koren Widdel said Costco was directly contacting members who purchased plants within the relevant timeframe. Santa Cruz County Agricultural Commissioner David Sanford said Costco had been “responsive and helpful” and that the problem occurred at the nursery supplier level, not at the retailer. Napa County said its local Costco received multiple shipments totaling 220 grapevines from Burchell Nursery, Inc. in Fresno County, and that all life stages of the insect had been detected on related shipments across multiple counties. (cdfa.ca.gov) ### What are officials telling people in Santa Clara County to do? Santa Clara County told residents who bought a grapevine from Costco in an affected county between April 21 and May 19 to keep the plant in its original pot or container and away from other plants. The county said residents should not put the plant in the ground if they have not already done so and, if possible, should place it inside two trash bags and seal them. (smcgov.org) The county also said residents should not return, transport or relocate the plant, and should not put it in the trash or compost bin. Santa Clara County asked residents to email SCC.Agriculture@cep.sccgov.org or call 408-918-4600 and provide contact information, the number of plants purchased, the status of the plants and their location. ### Why is this insect drawing such a large response? (ag.santaclaracounty.gov) CDFA said the glassy-winged sharpshooter spreads the bacterium that causes Pierce’s disease, which it described as a fatal grapevine disease that threatens California vineyards. The agency also said the pest can damage citrus trees, landscape plants and other crops, and that early detection and rapid response are critical to preventing further spread. (ag.santaclaracounty.gov) Santa Clara County said the insect does not naturally occur in Northern California, though it is established in Southern California. The county described Pierce’s disease as lethal and said grapevines can die within two to five years. San Mateo County said the pest also threatens almond, citrus and ornamental plants, extending the concern beyond commercial vineyards to home gardens and landscaping. (cdfa.ca.gov) ### What happens after a resident reports a plant? Santa Clara County said an agricultural inspector will schedule an appointment to examine the affected plant and nearby host plants. If inspectors find the insect on the grapevine, the county said they will remove and dispose of the plant safely. The county added that monitoring traps may also be placed on or near the property. (ag.santaclaracounty.gov) CDFA said county agricultural commissioners, the state’s Pierce’s Disease Control Program and Costco are actively responding. San Mateo County said residents who think they have seen the insect in their yard should collect it and compare it with photographs on the state agriculture department’s website before calling local officials. ### How broad is the response now? CDFA’s May 29 alert listed more than 20 counties, including Santa Clara, where residents were told to contact local agricultural commissioners if they bought grapevines during the affected period. (ag.santaclaracounty.gov) County notices in San Mateo, Santa Cruz, Napa, Sacramento and Stanislaus show the response has spread well beyond one store or one county. As of May 29 at 10 a.m., CDFA said the agency was maintaining a statewide list of impacted Costco locations by county on its alert page. (cdfa.ca.gov) For Santa Clara County residents, the next step remains a direct report to the county agriculture office at 408-918-4600 or SCC.Agriculture@cep.sccgov.org so inspectors can arrange visits and, if needed, remove infested plants.