Glassy Winged Sharp Shooter Adult on Grape Leaf
Glassy Winged Sharp Shooter Adult on Grape Leaf

Single Adult Glassy-winged Sharpshooter Intercepted

Author: Brenda Ouwerkerk, Chief Deputy Agricultural Commissioner
Date: Monday, August 28, 2017 10:48 AM

Results from timely follow-up by the departmental Pest Detection Trappers determine no additional Sharpshooters found.


On July 13, 2017,  a departmental Pest Detection Trapper found one single adult Homalodisca vitripensis, Glassy-winged Sharpshooter (GWSS) on an insect trap in a citrus tree located on a commercial property on the west side of the city of San Luis Obispo. 

Departmental staff took immediate action to determine if additional Sharpshooters were present by conducting a one quarter mile radius visual survey and a high-density trapping delimitation survey encompassing a one mile radius from the citrus tree find site.

The extensive trapping resulted in no signs of the presence of additional GWSS.  Trappers placed 117 insect traps and performed approximately 671 total trap inspections, searching for adult sharpshooters.  “The purpose of the intense trap monitoring by the Pest Detection Trappers was to determine if the single sharpshooter was a solo sharpshooter inadvertently transported to the site or if a breeding population existed”, according to Martin Settevendemie, Agricultural Commissioner/Sealer.  “No signs of an established or breeding population were detected.  The keen eye, quick response by staff and cooperation of residents that hosted traps are key to keeping unwanted pests from becoming established and damaging crops”, continued Settevendemie.  At this time control treatments will not take place.

The visual survey also yielded no evidence of egg masses, larvae or adults in the 400 properties inspected. 

The Glassy-winged Sharpshooter is an insect capable of transmitting the bacterium Xylella fastidiosa, which is responsible for multiple plant diseases including Pierce’s Disease, which is fatal to grapevines.   Pierce’s Disease does not affect human or animal health.