Pests and Diseases
Glassy-Winged Sharpshooter (GWSS)
The Glassy-Winged Sharpshooter (GWSS) is a non-native pest (meaning it was not originally found in California). The GWSS spreads a variety of diseases to crops and ornamental plants including Pierce's Disease - a disease about which you may have heard and which infects grapevines. Pierce's Disease blocks the circulatory systems of a plant, choking off its food and water supply. The GWSS is so dreaded because it is voracious and highly mobile and can spread Pierce's Disease from plant to plant quickly and easily.
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A typical GWSS will drink approximately 13 milliliters of water per day (200-300 times its own body weight) - which it sucks from the unfortunate host plant. That's the same thing as a human drinking 4,300 gallons of water per day!
What you can do to help:
- Go to www.bugspot.org to learn more about the GWSS. If you think you have spotted a GWSS, call 1-866-BUG-SPOT.
- Look for the Certificate of Compliance at your local nursery or landscaper's office. This means that they have been inspected by the Napa County Agricultural Commissioner. Be vigilant in buying locally.
- Check your outdoor plants regularly. Be on alert for the GWSS when walking in local parks and recreation areas.
While the State of California enacted emergency regulations to stop the spread of the GWSS, it is the consensus of the Napa Valley wine industry that these regulations do not go far enough. As a result, Napa County has enacted the toughest regulations in the state to stop the harmful pest from ever entering our county. The NVV, along with former Senator Wes Chesbro, also sponsored legislation- that was signed by then Governor Gray Davis- to allow a mandatory assessment on vineyard land in Napa County creating a permanent source of funding for Napa County's work plan.
One significant reason for these tougher regulations is so that we will never have to be put in the position of using pesticides to eradicate the GWSS. The Napa Valley plan was developed by the Glassy-Winged Sharpshooter Action Team -- the Napa County Agricultural Commissioner, the wine industry, the nursery industry, and environmental groups -- and approved by the State Department of Food and Agriculture.
For further information about the Glassy-Winged Sharpshooter or the Action Plan - visit the Web site of the Napa County Agricultural Commissioner at www.co.napa.ca.us/gov/departments/deptdefault.asp?did=26400








