California agriculture officials are scrambling to contain a potentially devastating invasive insect outbreak after dangerous pests were discovered on plants sold at Costco stores across Northern California.
Urgent Consumer Alerts Issued
Authorities in multiple counties issued urgent consumer alerts this week after glassy-winged sharpshooters — an invasive insect capable of spreading a deadly grapevine disease — were found on grapevines and citrus plants shipped to Costco locations from a Fresno County nursery. Officials warned the insects pose an immediate threat to California's multibillion-dollar wine industry, along with citrus orchards, backyard gardens and other crops across the state.
The infestation has triggered emergency responses in Napa, Sonoma, Marin, Solano, Butte and several other counties, with agriculture departments urging residents who recently purchased plants from Costco to contact authorities immediately.
Community Cooperation Critical
'Glassy-winged sharpshooters pose a serious and immediate threat to vineyards, agriculture, and backyard plants,' Solano County Agricultural Commissioner Ed King said in a statement. 'Community cooperation is critical right now.'
The insects were detected on shipments from Burchell Nursery in Fresno County, which officials say failed to notify county agriculture offices before shipping plants — a requirement under California quarantine laws.
Costco Not at Fault
Officials stressed that Costco itself was not responsible for the outbreak. 'Costco is not at fault here, and they've been an exceptional partner throughout this process,' said Sonoma County Agricultural Commissioner Andrew Smith. 'They acted quickly, cooperated fully, and are working to notify members and customers as fast as possible.'
Customers who purchased grapevines or citrus plants from Costco stores since April 21 are being told not to throw the plants away, move them, or give them to others. Instead, residents are being instructed to tightly seal grapevines in two garbage bags and contact local agriculture departments for inspection and disposal guidance. Citrus plants must also be inspected before any action is taken.
Threat to Wine Industry
The glassy-winged sharpshooter, native to the southeastern United States, was first detected in California during the late 1980s and has since become one of the state's most feared agricultural pests. The insect spreads a bacterium called Xylella fastidiosa, which causes Pierce's disease — a fatal infection that slowly dehydrates grapevines and destroys vineyards.
California's wine industry is especially vulnerable. The state produces roughly 80 percent of all US wine and contributes more than $70 billion annually to the economy, according to Wine Institute estimates. Pierce's disease devastated vineyards in parts of Southern California during the 1990s and early 2000s, costing growers millions of dollars before aggressive containment programs were introduced.
Wide-Ranging Pest
Experts say the glassy-winged sharpshooter is particularly dangerous because it flies farther and feeds on a much wider range of plants than native insects. In addition to grapes, the pest can spread diseases affecting almonds, peaches, plums, alfalfa and ornamental landscaping plants commonly found in residential neighborhoods.
'This is a devastating pest for our local vineyards,' said Napa County Agricultural Commissioner Tracy Cleveland. 'It is critical for us to track down any potentially affected plants.'
The discovery has rattled wine-producing regions including Napa and Sonoma counties, where vineyards form the backbone of local economies and tourism industries. California has spent decades building aggressive pest exclusion programs to prevent invasive species from damaging crops.
