Until just a couple of years ago, Costco (NASDAQ: COSTwas the wine industry\u2019s best friend, holding the title of the nation\u2019s top wine retailer until 2024 (1). Now, however, winemakers are worried the warehouse retailer could, inadvertently, wipe out segments of their vineyards.<\/p>\n
The Napa County agricultural commissioner issued an alert (2) on Tuesday, warning grapevines sold at Costco had been found to be infested with an invasive insect known as the glassy-winged sharpshooter (GWSS). The insect, which is roughly a half-inch in length, transmits bacteria that\u2019s linked to many plant diseases and can cause Pierce\u2019s disease (3) in grapevines, an incurable infection that blocks water-conducting systems in plants, drying them out.<\/p>\n
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A Costco nursery in Napa received 220 grapevines from Burchell Nursery, Inc., which were found to be infected. So far, 63 of those have been destroyed, but the remaining 157 are unaccounted for and officials say they could be in the possession of community members in the Napa area.<\/p>\n
\u201cGWSS is a devastating pest for our local vineyards, and it is critical for us to track down any potentially affected plants purchased at Costco or brought into Napa County,\u201d Napa County Agricultural Commissioner Tracy Cleveland said in a statement. \u201cVigilance and prompt reporting are essential.\u201d<\/p>\n
Doubling down on troubles <\/p>\n
The threat of Pierce\u2019s Disease is a substantial one. The California Department of Food and Agriculture invests annually in a program to prevent and control the disease and the spread of the glassy-winged sharpshooter. Without those efforts, the department says (4), growers\u2019 losses would more than double from $48 million to $104 million \u2014 and an unchecked spread could cost winegrape growers an additional $56 million a year in lost production and vine replacement.<\/p>\n
Replacing any diseased vines would take years, which could dramatically impact the California wine region economy, as well as impact tourism.<\/p>\n
That comes as the wine industry saw an unprecedented contraction (5) in 2025, with the largest one-year drop in volume. California alone saw a year over year shipment loss of $142 million, which represented 62% of the industry\u2019s total value decline.<\/p>\n
Tasting-room traffic is down as well, and has been for several years. \u201cRelying on people coming to the tasting room no longer works,\u201d one winemaker told Silicon Valley Bank in its 2026 State of the U.S. Wine Industry report (6).<\/p>\n
Read More: Taxes are going to change under Trump\u2019s \u2018big beautiful bill\u2019 \u2014 4 reasons you can\u2019t afford to waste time<\/a><\/p>\n Protective steps <\/p>\n To stop the spread of Pierce\u2019s Disease, Napa officials are asking (7) anyone who might have bought an infected vine to not plant it \u2014 and to keep it isolated in its original pot or container. If possible, they urge, put the plant(s) in two secured trash bags, sealing them both.<\/p>\n Do not, they stress, attempt to return the plant or move it in any way. And don\u2019t put it in the trash or compost. Instead, they ask that consumers contact the Napa County Agriculture Commissioner\u2019s office, who will send out an inspector that day to examine the grapevine and any nearby agriculture where the glassy-winged sharpshooter might feel at home. They might also put down monitoring traps as a precaution.<\/p>\n You May Also Like <\/p>\n Join 250,000+ readers and get Moneywise\u2019s best stories and exclusive interviews first \u2014 clear insights curated and delivered weekly. Subscribe now.<\/a><\/p>\n Article Sources <\/p>\n We rely only on vetted sources and credible third-party reporting. For details, see our ethics and guidelines<\/a>.<\/p>\n Yahoo Finance (1)<\/a>; Napa County (2)<\/a>, (7)<\/a>; UC IPM (3)<\/a>; California Department of Food and Agriculture (4)<\/a>; Sovos (5)<\/a>; Silicon Valley Bank (6)<\/a><\/p>\n This article originally appeared on Moneywise.com<\/a> under the title: Invasive insects found in Costco plants could ‘devastate’ California’s wine country, costing millions<\/a><\/p>\n This article provides information only and should not be construed as advice. It is provided without warranty of any kind.<\/p>\n","protected":false},"excerpt":{"rendered":"Until just a couple of years ago, Costco (NASDAQ: COSTwas the wine industry\u2019s best friend, holding the title…\n","protected":false},"author":2,"featured_media":335919,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[7,9,8,2363,138170,138763,3938,138734,138762,14238,49914,138761],"class_list":["post-335918","post","type-post","status-publish","format-standard","has-post-thumbnail","category-california","tag-california","tag-california-headlines","tag-california-news","tag-costco","tag-glassy-winged-sharpshooter","tag-gwss","tag-napa-county","tag-pierces-disease","tag-plant-diseases","tag-robert-kiyosaki","tag-wine-industry","tag-wine-retailer"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/posts\/335918","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/comments?post=335918"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/posts\/335918\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/media\/335919"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/media?parent=335918"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/categories?post=335918"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/tags?post=335918"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}