What Are Invasive and Exotic Pests?

Many invasive or exotic pests are of major concern in California. The glassy-winged sharpshooter (a type of leafhopper) and purple loosestrife (a weed) are two invasive species that are firmly established in some areas and threaten to invade other areas. New invasive/exotic problems include the Diaprepes root weevil, Mexican fruit fly, and Asian citrus psyllid. Insect-carried diseases such as West Nile virus also threaten people, horses and native birds.

People frequently bring plants, animals and insects with them to California, either accidentally or intentionally. Sometimes these introductions can do extensive damage. Many plant problems start with exotic ornamental plants that are for sale by nurseries and garden centers. Other exotic species such as insects arrive in products brought into California by travelers or shipped in commercial trade.

What can you do to help stop the spread of exotic and invasive species? Don't bring plant or animal material into California. Respect any local quarantine areas. Report invasive species in your area! Contact your local Agricultural Commissioner to report invasives and to get information on controlling invasive species on your property.

Learn to identify invasive species new to California. See our pages on these problem insects, plants, and diseases. Contact your local Agricultural Commissioner for help identifying suspected invasive species.