Oh Oh – There’s A New Sharpshooter In The County

From the Contra Costa County Department of Agriculture/Weights & Measures

Invasive Glassy-Winged Sharpshooter Found on Plants Sold at Multiple County Locations

(Martinez, CA) – The Contra Costa County Department of Agriculture / Weights & Measures is issuing an urgent consumer alert after the invasive glassy-winged sharpshooter (GWSS) was found on grapevines sold at five Costco locations across Contra Costa County. The detections are part of a broader statewide incident involving nursery shipments distributed to multiple California counties

The nursery shipped the plants without pest notification, and the shipment arrived without certification. An estimated 200 plants were sold before the infestation was detected. The plants were distributed across five Costco locations in Danville, Concord, Brentwood, Richmond, and Antioch. Remaining inventory was destroyed after most plants were confirmed to have multiple life stages of GWSS present.

County officials are now working closely with state partners and other affected counties to locate and recover plants that may have been purchased and planted in residential landscapes. Costco is also attempting to contact all customers who purchased the plants and is asking customers to contact the Contra Costa County Department of Agriculture / Weights & Measures.

“The glassy-winged sharpshooter poses an immediate and serious threat to grapevines and agricultural landscapes throughout Contra Costa County. We are working closely with our state partners and other affected counties to get ahead of this, but we need the public’s help. If you purchased a grapevine at one of the affected Costco locations since April 21, please contact our office right away — do not move the plant, and do not put it in the trash. We will take it from there,” said Matt Slattengren, Contra Costa County Agricultural Commissioner.

Residents who purchased grapevines since April 21, from Costco locations in Danville, Concord, Brentwood, Richmond, or Antioch, should take the following steps immediately:

Keep the plant in its original pot or container and away from other plants.
Do not put the plant in the ground if you have not already done so.
If possible, place the plant in two trash bags, one inside the other, and seal them closed.
Do not return, transport or relocate the plants.
Do not place plants in the trash or compost bin.
Contact the Contra Costa County Department of Agriculture / Weights & Measures at (925) 608-6600 to schedule pickup of grapevines and receive guidance on preventing further spread.
GWSS monitoring traps may be placed on the property.

The glassy-winged sharpshooter is an invasive leafhopper, originally from the southeastern United States and Mexico. It was first detected in California in the 1990s and has since become established in parts of central and southern California. GWSS feeds on more than 300 plant species, including grapevines, citrus, almonds, and many ornamental plants commonly used in landscaping. In grapevines, GWSS transmits the bacterium Xylella fastidiosa, which causes Pierce’s Disease — a condition that diminishes vine health and can result in grapevine death, posing a serious and immediate threat to Contra Costa County’s agricultural industry. GWSS adults are approximately ½ inch in length.

For more information, contact the Agricultural Commissioner’s Office at (925) 608-6600 or AgCommissioner@ag.cccounty.us.