Yet another Oriental fruit fly infestation has been discovered in Southern California, the latest in a series of invasive pest problems that have surfaced this year in non-agricultural areas of Los Angeles and Orange counties.

The California Department of Food and Agriculture has established an eradication program for the Oriental fruit fly in the city of La Verne, about 35 miles east of Los Angeles, the agency said July 21 in a news release. Four of the pests were recently discovered in traps in La Verne, according to the release.

The Oriental fruit fly news release came one week after the department initiated an eradication program for a guava fruit fly infestation in the Orange County cities of Garden Grove, Orange and Santa Ana.

Neither of the infestations is close to Southern California’s commercial citrus and strawberry fields.

“Summer and fall are the most active seasons for fruit flies in our state,” CDFA Secretary A.G. Kawamura said in the release. “Now more than ever, we urge Californians who travel abroad not to bring back fruits, vegetables, seeds or other prohibited plant material.”

The Oriental fruit fly and guava fruit fly infestations come on the heels of the department’s declaring the eradication of two other pockets of pests. It lifted a 70-square-mile quarantine in and around the eastern Los Angeles suburb of Azusa July 13 after determining a Mexican fruit fly infestation had been eradicated. Less than a week earlier, department officials reported eradicating the Oriental fruit fly near Long Beach and the lifting of a similar quarantine.

Eradication programs do not include the establishment of quarantines; instead, a combination of a male attractant and a pesticide is sprayed on trees and utility poles at two-week intervals for two of the insect’s life cycles after the last pest is found in a trap, according to the release.

When the state agency imposes quarantines, the movement of fresh produce and nursery stock outside of established boundaries is restricted. Gardeners also are prohibited from transporting yard waste outside of the quarantine area.