Department of Agriculture/Weights and Measures Responds to Glassy-Winged Sharpshooter Detection

Author: David Aguayo, Asst. Agricultural Commissioner / Sealer
Date: 8/12/2026 4:00 PM

The County of San Luis Obispo Department of Agriculture/Weights and Measures completed a thorough survey after detecting a single glassy-winged sharpshooter (GWSS) in a local nursery, finding no additional GWSS or signs of an infestation. With ongoing monitoring traps in place and all results remaining clear, the outlook remains positive for protecting local agriculture and residential landscapes.

The adult insect was detected through the Department's Pest Detection Program and submitted to the California Department of Food and Agriculture, where laboratory specialists positively identified it as a GWSS.
Following confirmation on August 4, 2026, the Department immediately deployed staff to the detection site and conducted a visual survey of properties within a quarter-mile radius. With the cooperation and assistance of local agricultural producers and neighborhood residents, staff completed the survey without finding any additional GWSS or evidence of an established population.

As an additional aspect of our surveillance protocol, the Department placed over 60 insect traps throughout the area. These traps are routinely utilized to detect GWSS and will provide focused, ongoing monitoring for the remainder of the month. To date, no additional GWSS have been detected through either visual surveys or trapping activities.

GWSS is an invasive insect that feeds on the fluids of many plant species and poses a serious threat to agriculture because it can spread Xylella fastidiosa, the bacterium that causes Pierce's disease, a fatal grapevine disease that threatens California's vineyards. This bacterium is also responsible for other plant diseases such as oleander leaf scorch and citrus variegated chlorosis. GWSS along with the bacteria it spreads is not harmful to people or animals.

Preventing GWSS from becoming established in the county is essential to protecting vineyards, nurseries, commercial agriculture, and residential landscapes. Early detection, rapid response, and continued monitoring are critical to limiting the pest's spread and protecting the county's agricultural economy.

"The Department's early detection system worked exactly as intended," said Agricultural Commissioner, Martin Settevendemie. "The immediate response from our staff, along with the cooperation of local producers and residents, allowed us to thoroughly survey the area and quickly establish an expanded trapping network. Although no additional GWSS have been found, we will continue monitoring the area as a precaution."

The Department asks residents and agricultural operators to remain alert and report any suspected GWSS. Anyone who believes they have found the insect should contact the Department of Agriculture/Weights and Measures at (805) 781-5910.

Additional information about the glassy-winged sharpshooter and Pierce's disease is available through the California Department of Food and Agriculture at www.cdfa.ca.gov/pdcp.