Because many glassy-winged sharpshooters overwinter in citrus, citrus acts as a source of sharpshooters for neighboring vineyards. The bacteria multiply and block the water-conducting system of the plant causing water stress and eventual plant death. It also vectors the strain that causes oleander leaf scorch in oleander. The glassy-winged sharpshooter is a serious pest of grapes because it acts as a vector of the strain of Xylella fastidiosa that causes Pierce's disease in vineyards. In Kern County, warm winters that allow increased survival and pesticide resistance have resulted in increasing populations of sharpshooters that have become more difficult to control. Currently, insecticides are applied primarily to reduce sharpshooter populations that might move to grapes or to disinfest citrus trees before harvest. In recent years, however, very high numbers are rarely seen in Southern California-likely because of increased parasite activity. Consequently, the adults and nymphs excrete large amounts of liquid while feeding, which gives the fruit and foliage a whitewashed appearance.Įxtremely high numbers of glassy-winged sharpshooter have been shown to reduce fruit quality and yield of coastal lemons and Valencia oranges in Southern California. The insect feeds on the nutrient-poor xylem of the plant and must consume copious amounts of fluid in order to gain enough nutrition to grow and reproduce. The glassy-winged sharpshooter feeds, reproduces, and is often abundant on a variety of host plants including agricultural crops (citrus and grapes) and a large number of ornamental plants.

Glassy-winged sharpshooter will overwinter in citrus as well as weeds, ornamentals, and various trees (e.g., Eucalyptus windbreaks).

The first generation of glassy-winged sharpshooter become adults by mid-June, and the number of young adults continues to increase through July and August. Citrus is an especially attractive egg-laying host during late March through April and again in late June through August. In late winter and early spring, adults become active. The glassy-winged sharpshooter has two generations per year in California. Nymphs hatch in 10 to 14 days and proceed to feed on the leaf petioles or small stems. The female covers the leaf blister with a secretion that resembles white chalk and is more visible than the leaf blister. When it is first laid, the egg mass appears as a greenish blister on the leaf. These spots are helpful in distinguishing glassy-winged sharpshooters from smoke-tree sharpshooters, which have light-colored wavy lines on the head.įemales lay their eggs in masses of about 5 to 15 in the lower leaf surface of young, fully developed leaves. The head is brown to black and covered with numerous ivory to yellowish spots. Adults are about 0.5 inch long and are generally dark brown to black when viewed from the top or side. The glassy-winged sharpshooter is a large insect compared to other leafhoppers. Infestations that have appeared in various other counties in Central and Northern California have been eradicated or suppressed. The glassy-winged sharpshooter continues to spread slowly northward in the Central Valley. Its current distribution in agricultural areas is Southern California and Kern, Tulare, and Fresno counties. Glassy-winged sharpshooter was introduced into Southern California in the late 1980s. Glassy-winged sharpshooter is in the same insect family as leafhoppers (Cicadellidae).

Sharpshooter