Be on the lookout for invasive species threatening California! While state and federal agencies actively monitor for new invasive pests, the public serves a critical role in early detection and often are the ones who find new invasive species first.
During California Invasive Species Action Week (CISAW), take time to sharpen your invasive species identification skills to help protect California’s environment and economy. Below are three invasive species not yet established in the state. Your vigilance could make all the difference in stopping them from establishing and spreading.
Japanese Beetle
The Japanese beetle is metallic green with copper-colored wings and has a row of five white patches on each side. It feeds on over 300 plant species, with preferred host plants being roses, grapes, and cherry, among others. Adult beetles skeletonize leaves, harming flowers and fruit, while larvae (white grubs) feed on turfgrass roots damaging lawns. It is most common in the Eastern States where it is known to travel on nursery plants, sod, soil, vehicles, and luggage.
There are many high-risk entry points in California due to frequent travel and cargo shipments from infested regions, as well as nurseries and sod farms receiving out-of-state materials. The California Department of Agriculture (CDFA) maintains a statewide network of 12,000 traps to identify new introductions and monitor detections. Although the Japanese beetle is not established throughout California, local infestations do occur, and ongoing invasion is considered a threat. Be on the lookout for Japanese beetles or their damage. To learn more about Japanese beetles and active treatment areas, visit https://www.cdfa.ca.gov/plant/JB/.
Emerald Ash Borer
The emerald ash borer is another metallic green beetle that causes significant tree damage, including D-shaped exit holes, bark splitting, and crown dieback. It can cause tree death within 2–4 years. Emerald ash borer eggs and larvae are easily spread through the movement of firewood, ash logs, or wood packaging, and the adults can hitchhike on nursery stock, vehicles, and outdoor gear. It is widespread in the Midwest and Northeastern states but has been slowly spreading west.
Emerald ash borer has not yet been recorded in California, but its discovery in Oregon in 2022 increases the risk to our state. National parks and campgrounds are especially vulnerable to introductions from infested firewood. Be on the lookout for emerald ash borer and any signs of infestation. Visit https://www.dontmovefirewood.org/ for more information on protecting our forests.
Spotted Lanternfly
The spotted lanternfly is a large planthopper insect. Adults have light brownish-grey wings with black spots and speckled bands, while nymphs are black with white spots, later turning red and black with white spots. It sucks sap from plants causing oozing sap, leaf wilting, and sooty mold. Spotted lanternfly poses a serious threat to grapes, fruit trees, and hardwood trees. It is easily spread to new areas because it lays egg masses on vehicles, RVs, trailers, railcars, firewood, and outdoor gear. Egg masses are small and blend in well, making them hard to detect, and easily transported.
Spotted lanternfly is primarily established in the Northeastern U.S. In California, high-risk entry points include interstate highways (I-5, I-80, I-10), warehouses receiving goods from infested states, rail yards, airports, shipping docks, heavy freight and any vehicle traffic from the Eastern States. Be on the lookout for spotted lanternfly insects and egg masses. To learn more about spotted lanternfly visit https://www.cdfa.ca.gov/pdcp/board/spottedlanternfly.html.
Report a Pest
If you think you’ve seen any of these pests, or another new or unusual pest in your area, report it!
CDFA Pest Hotline: 1-800-491-1899
Report Online: https://www.cdfa.ca.gov/plant/reportapest/
Banner image: spotted lanternfly nymphs. Photo credit: Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org.