Glassy-winged sharpshooter found at Costco wine vines

glassy-winged sharpshooter – A major vineyard pest known to spread Pierce’s disease has been found on grapevines sold at Northern and Central California Costco stores between April 21 and May 21. Officials say the insect can kill grapevines, threaten wider crops, and could cost California

By the time the first grapevines were found under scrutiny in California, the worry had already moved beyond farms and into customers’ hands.

Between April 21 and May 21, grapevines were sold at Northern and Central California Costco stores, and authorities say those plants included the glassy-winged sharpshooter—a small invasive insect considered a major threat to California’s vineyards and the state’s $73-billion wine industry.

The insect was first identified and detected May 19 from grapevines sold at a wholesaler in Fresno. From there. the stakes tightened: the sharpshooter can spread Xylella fastidiosa. a strain of bacteria that kills grapevines by clogging their water-conducting vessels (xylem). The disease caused by that bacteria is called Pierce’s disease.

Officials say the risk doesn’t stay neatly inside vineyards. Several strains of the bacteria exist and can infect other host plants, including citrus, stone fruits, almonds, oleander and some shade trees, according to the California Pierce’s Disease Control Program.

If the pest is left unchecked, the California Department of Food and Agriculture says the disease could cost the California wine industry $166 million annually. For a state wine economy that supports more than 422,000 jobs statewide, the threat is not abstract.

The insect itself is small enough to be missed. but its features are specific: it has a flat triangular head. large eyes and clear wings. The head is brown to black with several ivory to yellowish spots. a look that helps separate it from its native counterpart. the smoke-tree sharpshooter. Fully grown adults can grow up to about half-an-inch.

Officials have been trying to catch up to the reality that the vines were already in retail reach. California Secretary of Agriculture Karen Ross said in a press release. “While many vines have been intercepted and destroyed. locating the thousands that may still be in customers’ hands remains our top priority.” She added that anyone who purchased these vines should contact their local agricultural commissioner immediately.

The state’s urgency is rooted in history. The glassy-winged sharpshooter was first reported in California in the early 1990s. The insect was first identified as a threat in August 1999. when more than 300 acres of grapevines in Temecula were infested with the glassy-winged sharpshooter and Pierce’s disease and were subsequently destroyed. according to the CDFA.

Pierce’s disease has a measured, expensive trail. A March 2025 report titled The Costs of Pierce’s Disease in the California Grape and Wine Industry estimates the disease has cost growers and government agencies about $110 million a year in losses and compliance costs. The CDFA also says up to 13. 000 grapevine plants potentially infected by the bacteria have been sold across a total of 24 Northern and Central California counties.

In its response, the CDFA says it is destroying infested stock still in Costco warehouses and working with agricultural commissioners while conducting public outreach to locate vines sold to consumers across 24 counties, as well as neighboring at-risk counties.

Authorities say they are responding to public reports, conducting inspections and public outreach, and trapping near stores and locations where purchased vines were taken. They are also ensuring that potentially infested plants are safely contained and disposed of.

Costco, too, has been pulled into the effort. The CDFA says Costco worked with the agency to notify customers, issue refunds to those who purchased the grapevines, and assist in connecting them to local agricultural officials in the impacted counties “for inspection and disposal guidance.”

Residents in the impacted counties are being asked to follow strict steps: isolate the plant, wrap it in double trash bags, and contact their county agricultural commissioner.

The pressure now is time and reach—what officials can intercept before a plant already in someone’s home becomes a pathway for a bacteria that can spread. And the insect’s footprint, officials say, extends far beyond grapes.

The glassy-winged sharpshooter is native to the southeastern U.S. and northeastern Mexico, giving the state a long view of how pests like this can take hold once they arrive. The question facing California’s wine-growing communities is whether this detection. tied to specific store dates and counties. can stop Pierce’s disease before the costs climb again.

glassy-winged sharpshooter Pierce’s disease Xylella fastidiosa California wine industry Costco grapevines Fresno Temecula Karen Ross CDFA agricultural commissioner