Costco Customers Urged to Destroy Plants Linked to Deadly Grapevine Disease

(Photo: USDA)

California officials are warning locals that desert willow plants sold through Costco may be infected with an invasive insect known to carry an incurable, grapevine-killing disease.

The alert was issued for 200 plants sold at seven Costco warehouses in San Diego between June 24 and July 3. The plants have been identified as a potential carrier of the glassy-winged sharpshooter, a species of leafhopper accidentally introduced to California in the late 1980s. The bugs eat grapevines and are known to spread a bacterium that causes Pierce’s disease, an infection that kills vines by clogging their waterways.

Their presence poses a potentially catastrophic risk to the state’s $84 billion wine industry, and officials have moved swiftly to identify and eradicate the suspected outbreak.

Agricultural authorities have cautioned customers against relocating the desert willows, returning them to Costco or putting them in green waste. Instead, the plants should be double-bagged, sealed completely and deposited in regular household trash. If the desert willows have already been planted, customers should immediately contact their local agricultural inspector.

It’s the second glassy-winged sharpshooter infestation traced back to a Costco this summer. In late May, officials detected the pests in nursery grapevines sold at nearly two dozen wholesalers across the state. Authorities suspect that the vines may have been transported to residential homes in at least 38 counties, many of which are located in or near grape-producing regions.

Lawmakers requested $32.2 million in emergency funds from the USDA to fight the pests, which they warned could cost the economy as much as $104 million per year if left unchecked. The funding would be used to support tracing, surveying and trapping programs.

The largest modern outbreak of Pierce’s disease was reported in Temecula Valley, California, in the late 1990s. Over the course of around six years, the infection destroyed over 1,000 acres of wine grapes throughout the region.

For a full list of counties where infected plants are suspected to have been sold, refer to the California Department of Food and Agriculture’s advisory.