Orange County Braces for Fruit Fly Sprayings

Thousands of North County residents, in the midst of an all-out attack on the Mediterranean fruit fly, are being advised to take precautions next week as agriculture officials begin at least two aerial sprayings of pesticide over a 10-square-mile area.

Officials had hoped to limit the aerial assault with the pesticide malathion to one sweep Nov. 30 over portions of Fullerton, La Habra and Brea. The eradication effort was triggered by the discovery of a pregnant Medfly Friday in a guava tree in Brea.

But local agriculture officials said Tuesday that a second, and possibly third, spraying would be necessary because of a critical shortage of sterile Medflies, which usually are released by the millions in an attempt to breed out of existence any fertile flies that survive the pesticide spraying.

“We’ve been told there are no sterile Medflies for Orange County,” said Frank Parsons, the county’s chief deputy agriculture commissioner. “We would prefer to conduct one aerial application and follow up with releases of sterile flies. But it’s not possible at this point. That means there will be at least two sprays.”

The first is scheduled for a week from Thursday night when pesticide-laden helicopters will sprinkle neighborhoods with a semisweet mixture of malathion and corn syrup that attracts the crop-destroying pest. Within a week a second spray is expected to take place, though no specific date has been determined, officials said.

The spray area is roughly bounded by Euclid Avenue on the west, La Habra Heights on the north, Brea Boulevard on the east and north Fullerton on the south.

State officials, already reeling from at least seven Medfly outbreaks in Los Angeles County, began deploying staff and resources to Orange County on Tuesday to cope with the widening crisis. Preparations were being made for the arduous task of notifying thousands of homeowners and businesses in the affected area, which includes a slice of La Habra Heights in unincorporated Los Angeles County.

About 200 members of the California Conservation Corps will go door-to-door in the spray area on Monday handing out leaflets in both English and Spanish announcing the pesticide spray, as well as addressing the use of malathion. The notices also carry special “Medfly Hot Line” phone numbers that people with questions can call.

State scientists insist that the pesticide poses no health risk, but others say it damages car paint and can make pets sick if they are left outdoors.

During the spray, officials advise residents to stay indoors, cover their cars if they park them outside and put dogs and cats in garages or under cover. Shallow back-yard fish ponds should also be covered, but officials say pool owners should not worry because the pesticide will not significantly affect the water quality in a standard-sized pool.

“These are simply precautionary steps,” Parsons said. “We do not believe that the malathion presents any real danger.”

No new fertile Medflies have been found in Orange County since Friday, when a pregnant female fly was found in a county trap set in a front-yard guava tree near the intersection of Puente Street and West Walling Avenue in Brea. The alarming discovery--which was not announced until Monday--has prompted officials to place about 1,000 traps within a 10-square-mile area, including 100 within a mile of the tree where the fly was trapped. The triangular-shaped traps--about 6 inches long and 3 inches high--will be inspected daily by a hastily assembled team of state and local experts for at least one more week, Parsons said.

“So far all we’ve captured are sterile Medflies,” said Parsons, adding that the sterile flies are probably among those released in recent weeks in Los Angeles County.

The sterile flies are produced at one of three Medfly breeding facilities in the world, and can be easily identified under a black light because they have been treated with a special dye, said Brian Taylor, a state entomologist.

Officials at a sterile Medfly breeding facility in Mexico have stepped up production to supply 50 million flies weekly to Los Angeles County. In addition, a California-run breeding facility in Hawaii, California’s usual source of sterile flies, has increased production to 130 million a week, but most of those are also going to Los Angeles County.

So far, state officials have chosen not to tap a third source of sterile Medflies in Guatemala, fearing that some of the flies may be fertile. Some scientists now believe that during Southern California’s last Medfly crisis, in 1981, a shipment of supposedly sterile flies from Peru contained some fertile flies that actually contributed to the infestation.

Because millions of sterile flies are released in infested areas several times a week, the demand for sterile flies is outstripping the supply.

“In areas where sterile flies have been released, it doesn’t make sense to switch back to spraying because it will kill many of the sterile ones, negating the effort,” Taylor said. “Once committed to using sterile flies, it makes sense to stick with it.”

Consequently, Orange County officials are crossing their fingers that no new outbreaks occur.

“Otherwise we’ll have no choice but to spray and that’s not a popular alternative,” Parsons said.

FORTUITOUS MOMENT--The Medfly poses a minimal threat to the county’s nursery industry and agriculture at this time of year. D1

Hot Lines for Medfly Questions

Aerial pesticide spraying is scheduled for Nov. 30 over a 10-square-mile area to combat a possible Mediterranean fruit fly infestation.

Residents in the affected areas, including portions of Fullerton, La Habra and Brea, as well as unincorporated La Habra Heights in Los Angeles County, may call (800) 225-1346 or (714) 447-7118 with questions or concerns about the spraying. The two “Medfly Hot Lines” were established by state officials to deal with concerns about the widening infestation.