4th Medfly Found; Spraying Termed Successful : No More Aerial Efforts Expected in Valley Alert

A fourth Mediterranean fruit fly was found just hours before two helicopters sprayed a 16-square-mile area of the San Fernando Valley with pesticide, but the eradication effort will not be expanded, officials said Tuesday.

“Our plans call for ground treatment initially and no air applications are planned at this time,” Bill Edwards, chief deputy for the county Department of Agriculture, said Tuesday.

The fourth Medfly was found Monday in a peach tree at a home in the 8400 block of Melvin Avenue in Reseda, a quarter-mile west of the zone treated with malathion.

Two helicopters, laden with 1,100 gallons of the malathion mixed with a corn-syrup bait, began spraying the infested area at 10 p.m. Monday and concluded the mission at 3 a.m. Tuesday.

Each helicopter made three passes at 500 feet over the spraying area, which included sections of Northridge, Reseda and Sepulveda, and the mission was a success, said Edwards.

“There were no complications. It was a good, clean operation,” he said.

The malathion bath was “a one-time shot” and the next step will be next week’s release of about 20 million cobalt-treated sterile flies, and daily releases thereafter to prevent females that escape the poison from reproducing, he said.

Quick Response

“A quick knockdown with an aerial application of malathion followed by the release of sterile flies has been effective in eradication,” said county Agricultural Commissioner Leon Spaugy.

The Medfly, common in Hawaii and probably carried into Southern California on fruit brought in by tourists, has a potential for spreading rapidly. Spaugy said aerial spraying was designed “to minimize that as much as possible.”

Residents were warned to keep pets inside and to cover automobiles and fish ponds to prevent damage.

Agricultural workers discovered a male fly inside a trap set in an apple tree Monday morning, about a mile from where two flies were found July 20, said agricultural department spokesman Bob Donley.

“It signals a potential quarantine,” he said. “Geographic boundaries will likely be set up and residents will be asked not to take any home-grown vegetables or fruits out of the area.”

Monday’s fly discoveries did not affect the boundaries set for the aerial spraying because they were so close to the target spray area, Donley said.

Medflies prey on more than 250 varieties of fruits and vegetables, depositing their eggs inside the produce and destroying it. Gov. George Deukmejian declared a local state of emergency Thursday, a prerequisite before spraying could begin.

Meanwhile, concerned residents deluged hospitals and the county’s Medfly hot line with questions about possible health hazards from the spraying. “We’ve had a few--a few thousand calls,” said Robert Dingfelder, a county agricultural inspector.