Westwood Fruit-Fly Find Triggers Quarantine

California’s $26-billion agriculture industry--already racked by infestations of the Mexican, Mediterranean and Oriental fruit flies--is being hit by the olive fruit fly.

State officials said Friday they had created a 58-square-mile quarantine zone in Southern California after 10 olive fruit flies were detected in the Westwood area of Los Angeles.

The California Department of Food and Agriculture said the discovery marked the first time the pests had been detected in the United States.

Normally found in olive-growing regions of Europe and North Africa, the insects could pose a threat to California’s olive crop, valued at $66.8 million in 1997. The department noted that California is the nation’s sole producer of commercially grown olives.

Earlier this year, Australia, New Zealand and South Korea banned imports of fresh fruit from San Diego County because of an infestation of the Mexican fruit fly.

Officials said that, unlike the Mediterranean fruit fly, which affects up to 250 varieties of fruits and vegetables, the olive fruit fly only poses a threat to wild and domestic olives.

Department spokeswoman Myrlys Williams said the department suspects that a traveler inadvertently brought the flies into the United States or that they arrived in a shipment of tainted olives.

Authorities said they had asked residents in the quarantine zone not to move olives from their properties. In addition, teams have started stripping olives from trees on all properties where olive fruit fly larvae have been found.

Officials said beginning this week, in an attempt to eradicate the insects, they will apply a pesticide to olive trees within a 200-meter radius of where each fly was found.

Because the insects can live up to five months inside the fruit in their pre-adult stage, authorities will have to resume treatments against the fly next spring.