05/30/2026
🚨 Grower & Gardener Alert 🚨
California agricultural officials are urging consumers to check any grapevines, citrus trees, or other fruit-bearing plants purchased from Costco between April 21 and May 26, 2026, after shipments from a Fresno County nursery were found to contain the invasive Glassy-Winged Sharpshooter (GWSS).
GWSS is one of the primary vectors of Pierce's Disease, a bacterial infection that can be fatal to grapevines and poses a significant threat to California's wine industry. There is currently no cure.
Affected plants were distributed to Costco locations throughout Northern California, including Sonoma, Napa, Marin, Solano, Yolo, Sacramento, Santa Clara, San Mateo, Alameda, Contra Costa, Placer, Stanislaus, and Yuba counties.
Officials are working with Costco to locate potentially affected plants and contact purchasers directly. In Napa County alone, 157 grapevines sold through Costco remain unaccounted for, highlighting the importance of locating and inspecting any potentially affected plants.
If you purchased grapevines, citrus trees, or other fruit-bearing plants from Costco between April 21 and May 26:
• Do not move or dispose of the plant
• Keep it isolated if possible
• Contact your local County Agricultural Commissioner's Office for inspection guidance
Early detection is critical to protecting California vineyards, wineries, backyard grape growers, and agricultural communities.
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