San Mateo and Santa Clara County officials are inspecting areas in Palo Alto, East Palo Alto and Menlo Park after two male peach fruit flies native to southern Asia were found in Palo Alto, with plans to begin eradication treatments this Thursday.
County officials trapped the bugs in Palo Alto on June 28 and July 2, then began placing insect traps in a 4.5-mile radius from the discovery sites.
"These finds are the result of early detection trapping which is key to finding and eradicating exotic pest infestations before they can become widely established," San Mateo County Agricultural Commissioner Fred Crowder said in a statement.
Currently, the treatment plan to eradicate peach fruit flies in the Midpeninsula cities won't affect private properties and no one will be under quarantine.
Starting Thursday, trained applicators from the state Department of Food and Agriculture will place spinosad, an organic pesticide, on trees, light poles and other far-to-reach, elevated locations about 8 to 10 feet above the ground within a 1.5-mile radius from where the fruit flies were found. The material is known to attract male fruit flies who die after consumption.
Peach fruit flies, commonly found through most of mainland southern Asia and neighboring islands, are known to attack about 50 kinds of fruits and vegetables, San Mateo County officials said in a statement. The produce becomes spoiled when a female peach fruit fly lays eggs that hatch into larvae.
The invasive bugs behave like regular fruit flies, but are considered a threat to native wildlife. San Mateo County currently has over 4,250 "exotic pest detection" traps countywide. Other bugs in the category include the gypsy moth, Japanese beetle, and a range of non-native fruit flies.
According to San Mateo County officials, exotic pests usually hitchhike on fruits and produce transported illegally from other countries.
The two counties, the state Department of Food and Agriculture and the U.S. Department of Agriculture will assess the bugs' spread and use organic pesticide for extermination.