October 2026

View as Webpage

• Update on Nursery Shipment Incidents

• New Glassy-Winged Sharpshooter Infestation in Sacramento County

• New Funding and Expert Review Support GWSS Eradication Efforts



• Upcoming Events

Update on Nursery Shipment Incidents

GRAPEVINES

State and county agriculture officials have completed trace-forward trapping related to the nearly 10,000 grapevines shipped to 40 Northern California counties earlier this year.

Officials found glassy-winged sharpshooters (GWSS) on grapevines in 22 counties, including 15 adults in 10 counties. No new GWSS have been detected at trace-forward sites since Aug. 13.

Routine GWSS detection trapping will continue through the fall and resume in early summer 2027. This trapping takes place in urban and residential areas and nurseries to detect new GWSS infestations and confirm that areas without GWSS remain pest-free. Additional trapping related to the nursery shipment incident could resume in early 2027 if funding is available.

DESERT WILLOWS

Officials continue working to locate desert willow plants shipped from Texas that carried GWSS into California earlier this year. As of Sept. 8, of the 3,120 plants shipped to 87 Costco stores in 25 counties, 2,730 were inspected and 1,609 destroyed. The California Department of Food and Agriculture confirmed 330 GWSS egg masses on inspected plants. The Texas nursery remains unable to ship plants to California until it addresses the pest issue.

People who suspect they have found GWSS should contact their local agricultural commissioner’s office. For pictures of the pest and for more information, visit bit.ly/GWSS-Costco.

New Glassy-Winged Sharpshooter Infestation in Sacramento County

Officials declared a new glassy-winged sharpshooter (GWSS) infestation in South Sacramento. It is the second active infestation in Sacramento County, following one discovered in Folsom in June.

Since August, officials have found 63 adults and two egg masses in South Sacramento. They are using traps and visual surveys to monitor the GWSS population. Response efforts include treating properties and releasing biological control wasps.

The infestation raises concerns about GWSS spreading farther into Northern California wine-growing regions. GWSS can spread Pierce’s disease, which kills grapevines, and feeds on hundreds of plants found in yards, landscapes and agricultural areas. More than 500 grape-growing properties in Sacramento County could be at risk. In 2024, the county had 37,173 acres of grapes valued at nearly $168 million.

GWSS eradication projects can take several years. The Pierce’s Disease Control Program currently oversees eradication work in five counties and has eradicated 18 GWSS infestations since 2001, including two in Sacramento County in 2009.

New Funding and Expert Review Support GWSS Eradication Efforts

This year's increase in glassy-winged sharpshooter (GWSS) detections and nursery shipment incidents have increased concerns about how eradication and control efforts can keep pace if more infestations are found.

The California Department of Food and Agriculture (CDFA) has committed $10 million, and the PD/GWSS Board has committed $1.5 million to support current eradication work.

CDFA is also taking steps to adapt its approach as new GWSS detections occur. It convened a Technical Advisory Group of university researchers, entomologists, plant disease and viticulture specialists, pest-management experts and county agricultural commissioners to review current eradication efforts and recommend improvements.

The group agreed that preventing GWSS from becoming broadly established in Northern California remains an important goal. It recommended continuing eradication work while improving trapping, infestation definitions and treatment strategies. The group also recommended ongoing expert review as eradication projects move forward and future response priorities are considered.

Upcoming Events

Stop by the PD/GWSS Board booth at the following grower events to connect with us and pick up the latest program information and outreach materials.

Grape, Nut & Tree Fruit Expo

Fri., Nov. 13 - BIG Fresno Fairgrounds in Fresno, CA

This free event offers PCA, CCA and INMP continuing education credits, complimentary breakfast and lunch and a trade show. Presentations will include updates on the wine, raisin and table grape industries, along with pest and disease management, water and nitrogen use efficiency, pesticide laws and regulations and other timely agricultural topics.

Tree & Vine Expo

Tues., Nov. 17 - Stanislaus County Fairgrounds in Turlock, CA

This free event offers PCA, CCA and INMP continuing education credits, complimentary breakfast and lunch and a trade show. Presentations will cover the wine grape and other major crop industries, along with irrigation, nutrient management, pesticide laws and orchard and vineyard pest, disease and weed management.

North Coast Wine Industry Expo

Thurs., Dec. 3 - Sonoma County Fairgrounds in Santa Rosa, CA

More than 250 exhibitors and a full day of educational sessions will bring together wine industry professionals from across the North Coast.

Be sure to attend “Understanding Red Blotch from All Angles: The Latest Research from Lab, Air & Vineyard,” led by Dr. Kris Lowe, PD/GWSS Board research coordinator. The session will cover the latest research on red blotch diagnostics, symptom expression, virus spread, advanced detection tools, aerial mapping and vineyard monitoring.

Use promo code “CDF721” to register for FREE trade show floor passes.

cdfa.ca.gov/pdcp | pdcpinfo@cdfa.ca.gov | (916) 900-5024