California’s ornamental plant trade accidentally imported the glassy-winged sharpshooter, but by 1999 it had triggered a Pierce’s disease outbreak so severe that more than 300 acres of grapevines in Temecula were destroyed

California’s ornamental plant trade introduced the destructive glassy-winged sharpshooter pest. This insect spreads Xylella fastidiosa, causing fatal Pierce’s disease in grapevines. A major 1999 outbreak devastated Temecula Valley vineyards, alarming the wine industry. Extensive monitoring and control programs were then launched by state agencies. Millions have been invested to manage this invasive insect’s impact.