Invasive pest found on Costco plants a threat to California Wine Country vineyards, officials warn
Authorities in Northern California alerted residents on Tuesday about an invasive species found on plants from Costco that could threaten the region's vineyards and other agriculture in the region.
Agriculture officials in Marin, Napa, Nevada and Solano counties issued a consumer alert "urgently asking residents to take immediate action" after glassy-winged sharpshooters were found on grapevines and citrus plants delivered to Costco stores.
The Napa County Farm Bureau said in a press release that all life stages of the insect were detected on grape vine shipments from Fresno County-based Burchell Nursery to multiple counties, including Marin, Napa, Solano, Sonoma, Yolo and other counties not named.
Marin Agricultural Commissioner Joe Deviney said in a press statement that Burchell Nursery was required by state quarantine laws to notify ag offices before shipping, "and that did not occur."
"Costco is not at fault here, and they've been an exceptional partner throughout this process," Deviney added. "They acted quickly, cooperated fully, and helped us reach customers as fast as possible."
Costco was directly contacting customers who purchased affected plants within the timeframe, Deviney said.
The glassy-winged sharpshooter (Homalodisca vitripennis) is a large leafhopper insect native to the southeastern United States. First detected in California in the late 1980s, it has since become one of the state's most significant agricultural threats for its role as a vector for a deadly plant bacterium that causes Pierce's disease which fatally dehydrates grapevines.
"GWSS 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," Napa County Agricultural Commissioner Tracy Cleveland said in a press release.
"Glassy-winged sharpshooters pose a serious and immediate threat to vineyards, agriculture, and backyard plants throughout Solano County and surrounding regions," Solano County Agricultural Commissioner Ed King said in a statement. "These insects spread the bacterium that causes Pierce's disease, which can kill grapevines and severely impact vineyards. Community cooperation is critical right now."
Officials urged anyone who recently purchased grapevines or citrus plants from Costco since April 21 to contact their county's Agriculture Department so staffers can contain and eliminate the threat.
Residents were directed to place two garbage bags over grapevines to secure them tightly. For citrus plants, people were asked to contact the department to schedule an inspection. The department urged resident not to return, relocate, or give away the plants, and not place them in trash bins or compost containers.
The glassy-winged sharpshooter flies higher and farther that native sharpshooters, and can thrive in commercial citrus orchards often planted right next to vineyards. The Xylella fastidiosa bacterium it spreads can also causes diseases in other major California crops such as almonds, alfalfa, peaches and plums, as well as a wide range of plants used in residential landscaping, according to University of California researchers.
