The discovery of several Mediterranean fruit fly adults and larvae in Los Angeles County has prompted the California Department of Food and Agriculture to implement an 88-square-mile quarantine.
The one adult male and five unmated females were detected in traps between March 3 and 12, according to a news release.
A subsequent delimiting survey of the area turned up four larvae in backyard fruit on March 18.
The quarantine includes an area near the University of Southern California.
In response to the finds, the state will begin an eradication program that involves doubling the release of sterile male Medflies over the area.
For several years, the state has conducted a maintenance program where they release 125,000 flies per square mile per week over the area.
With the new finds, the number increases to 250,000 flies per week over about a 25-square-mile area.
The theory is to inundate an area with so many sterile males that females will have a hard time finding a wild male with which to mate. Eventually, the population ties out for lack of reproduction.
In addition, properties within 200 meters of the finds are being treated with an organic formulation of spinosad insecticide. Crews also are stripping fruit from trees within 100 meters of the larval detections.
Under the quarantine, homeowners are urged not to move homegrown produce outside of their yards to prevent the spread of the pest.
Medflies can infest more than 250 different fruits and vegetables.