The latest insect to join this rogues gallery is the glassy-winged sharpshooter, which can infect plants with the deadly Pierce's disease. Glassy-winged sharpshooters are native to the southeastern United States, but were first found in California in 1990. Currently, they are most common in Southern California, and have been identified in ten California counties.
Sharpshooters feed on a variety of ornamental and crop plants.
Pierce's disease is caused by Xylella fastidiosa , a bacterium transmitted from diseased plants to healthy ones by sharpshooters feeding on sap. Eventually the bacterium will block the xylem, leading to severely reduced water flow to the leaves. Signs of water stress in affected plants generally begins in mid-summer, and increases through fall. In addition to Pierce's disease, X. fastidiosa also causes almond leaf scorch, alfalfa dwarf, oleander leaf scorch, and citrus variegated chlorosis. Due to their ability to spread Pierce's disease, tracking and eradicating glassy-winged sharpshooters is of major economic importance.