Pierce’s Disease, Xylella fastidiosa, is a bacterial disease of grape vineyards that has been established in Southern California agriculture for at least 100 years. The disease is responsible for decimating vineyards in Orange County in the early 20th century and recently in Temecula vineyards in Riverside County. An introduced insect from the southeastern United States, the Glassy-winged Sharpshooter (GWSS) is a voracious feeder on a wide array of edible and ornamental plants. As a side effect of its feeding, the Glassy-winged Sharpshooter is capable of vectoring Pierce’s Disease to susceptible plantings. A statewide program has been established in an attempt to restrict the movement of GWSS into the uninfested grape-growing areas of the state.
California Department of Food & Agriculture Information