Medfly Battle Heats Up but Air Spraying Isn’t Planned : Agriculture: Officials hope that 30 million sterile fruit : flies, ground spraying and a 53-square-mile produce quarantine will end the threat.

House by house, fruit tree by fruit tree, workers in the war against the Medfly have been going about their chores as agricultural officials express hopes of confining and eventually eliminating the pest that again poses a menace to community tranquillity and the state’s agricultural industry.

Some workers set out traps to catch the Mediterranean fruit fly or took traps from treetops to see if anything had been caught.

Others, including bug experts who have arrived from federal agricultural posts throughout the country, picked fruit from trees and laboriously cut it open to look for Medfly larvae.

And county, state and federal agricultural crews with hand-held spraying devices were making their way through the Pasadena and Altadena neighborhoods where an outbreak of the flies was discovered two weeks ago.

The focus of the anti-Medfly campaign is a 53-square-mile area where fruit, nuts and vegetables are now quarantined. The area extends from Angeles National Forest on the north; Alhambra, San Gabriel and Temple City on the south; Pasadena’s Fair Oaks Avenue and Altadena’s Sage Hill Road on the west, and Monrovia’s California Avenue on the east.

Within that area, ground spraying has been confined to 19 square miles in Pasadena and Altadena. Sterile Medflies--aimed at counteracting the spread of maturing fertile Medflies--will be released, also in the smaller area, starting Friday and lasting at the least through spring.

Agriculture officials said they hope to keep the public informed to avoid the controversy that occurred during the last major campaign against the Medfly in 1989 and 1990, when helicopters sprayed sticky Medfly bait laced with the insecticide malathion.

This time around, homeowners are notified when workers take their sprayers onto private property or take fruit from trees, said Larry Hawkins, a U.S. Department of Agriculture spokesman. In the case of spraying, there is 24-hour advance notice.

Workers ask residents for permission to spray trees and shrubs. No spraying is done if permission is denied, Hawkins said. If no one is home, workers leave a leaflet with the Medfly project’s phone number: (800) 491-1899.

The spraying takes place, however, if no one is home within 24 hours and no one calls to deny access, Hawkins said.

Disputing those who fear adverse health effects from even hand-held spraying, Hawkins said the malathion bait poses no health risk as it is being applied. Only trees and shrubs are sprayed, he said. “We don’t spray dog dishes.”

More important than the spraying is the release of sterile fruit flies, Hawkins said.

The release of the sterile flies will be done by aircraft and truck over the 19-square-mile area, including the Hastings Ranch area, where Medflies were first found in a trap Sept. 8.

Hawkins said residents should not be surprised to see concentrations of fruit flies over the next several months.

“Obviously, when we’re releasing 30 million flies each week, people are going to notice,” he said.

Hawkins said agriculture officials are buoyed by the success of an eradication program in the Koreatown area of Los Angeles, where an infestation in October was controlled without aerial spraying. He said officials hope that the same combination of sterile flies and ground spraying will work in the San Gabriel Valley too.

Only as a last resort, Hawkins said, will aerial spraying be instituted. “It’s the option we like the least,” he said.

Hand-held spraying, he said, “lets us apply it to where we need it.” To have malathion bait on autos, roofs and grass does no good because fruit flies don’t congregate in such places, he said.