Glassy-Winged Sharpshooter   Image by Brett Hondow from Pixabay

May 29, 2026 - The Merced County Department of Agriculture, in coordination with the California Department of Food and Agriculture (CDFA), announced today that while a portion of suspect nursery shipments from Costco have been successfully intercepted, several plants remain unaccounted for and are still in the possession of local Costco members.

The invasive Glassy-Winged Sharpshooter (GWSS)—a serious pest and destructive leafhopper—was recently detected across multiple Northern and Central California counties on shipments of grapevines, citrus plants, and fruit trees supplied by Burchell Nursery, Inc. Multiple life stages of the pest, including eggs, nymphs, and adults, have been confirmed on these shipments. Because Merced County received suspect inventory from these specific delivery blocks, local agricultural inspectors are engaged in a rapid-response campaign to locate the remaining purchases before any potential pests can escape and become established.

Costco Wholesale is acting as a fully cooperative partner, working closely with county agricultural commissioners to directly contact affected members. Officials emphasize that the food supply remains safe and that consumers are entirely blameless, as the infestation occurred strictly at the wholesale nursery supplier level.

"Our team has successfully intercepted a portion of these plants, but our job isn't done until every plant is accounted for," said Merced County Agricultural Commissioner Sean Runyon. "The Glassy-Winged Sharpshooter poses a threat to both commercial agriculture and backyard gardens. We need every Costco member who purchased plants recently to contact our office or their local agricultural commissioner so we can safely contain this threat at no cost to the resident."

Immediate Action Required from Costco Members

If you purchased a grapevine or other plants (fruit trees/bushes) from Burchell Nursery at Costco on or after April 21, 2026, please take the following containment steps immediately based on the plant type:

• FOR GRAPEVINES: Immediately place two heavy-duty garbage bags over the plant and container, and secure them tightly closed to prevent any insects from escaping. 
• OTHER PLANTS (fruit trees/bushes): Keep the plant completely isolated from other backyard vegetation. Do not plant it in the ground. 
• FOR ALL AFFECTED PLANTS: Do not attempt to return the plant to Costco, do not transport or relocate it, and do not place it in household trash bins or green-waste compost containers. 

Contact the Department of Agriculture Immediately

Please contact the Merced County Agricultural Department right away at (209) 385-7431 or email AgDeptEmail@countyofmerced.com to schedule a priority pickup of grapevines or an on-site inspection of citrus and fruit trees.

Upon notification, an agricultural inspector will be dispatched to examine the target plant and adjacent landscape hosts. If GWSS is detected, staff will ensure safe containment and disposal at no charge to the property owner. Precautionary monitoring traps may also be deployed in the surrounding neighborhood to ensure no pests escaped into adjacent foliage.

For more information on the Glassy-Winged Sharpshooter and Pierce’s Disease control programs, please visit the CDFA website or contact the Merced County Department of Agriculture.

Source: Merced County