Ground Spraying to Fight Medflies Starts Next Week : Infestation: Malathion will be used in Koreatown area. Officials also announce new, 47-square-mile quarantine district.

State and federal agricultural officials announced Friday that they will begin ground spraying of malathion in the Koreatown section of Los Angeles next week to eradicate what is thought to be a small Mediterranean fruit fly infestation.

At the same time, officials outlined a new, 47-square-mile quarantine area intended to help control the spread of the crop-destroying pest.

The decision to spray was made after a pregnant Medfly was trapped in a peach tree last Monday in the 1700 block of Catalina Street. It was the first such discovery in the state since last fall.

Officials said they will only spray a one-quarter-square-mile area--including 177 residential properties bounded by Venice Boulevard on the north, Washington Boulevard on the south, Walton Avenue on the west and Vermont Avenue on the east.

The spraying of a protein bait laced with malathion will begin Tuesday and last through Wednesday, officials said.

Since the discovery, crews have been placing more traps, cutting into fruit, and looking for Medfly larvae, Los Angeles County Agricultural Commissioner E. Leon Spaugy said Friday.

Officials also mapped out the quarantine area, which extends north to Sunset Boulevard, south to Slauson Avenue, west to La Cienega Boulevard and east approximately to the Harbor Freeway. They warned residents in the zone not to pick fruit to keep the infestation from spreading beyond the quarantine zone.

“At the present, we are dealing with a small, local infestation,” Spaugy said, adding that the controversial aerial spraying of malathion will not be required if the quarantine is successful.

In 1989, a Medfly was discovered in a trap near Dodger Stadium, and the infestation spread throughout Los Angeles, Orange, San Bernardino and Riverside counties. An eradication program--including controversial aerial spraying--cost $52 million. The infestation was declared eradicated in November, 1990.

Spaugy said officials are better equipped to battle the Medfly without aerial spraying because of new technology and a more adequate supply of sterile flies used to disrupt the pest’s breeding cycle.

“A year ago, the discovery of a mated fly would have triggered (the aerial) application of malathion,” the commissioner said.

“There is substantial evidence that this (find) has been a new introduction,” Spaugy said, adding that the evidence includes the recent interception of Medfly larvae in crop shipments from Hawaii.

However, some insect and agriculture experts say that the Medfly has been entrenched in some areas of California for about 15 years.

Medfly Action Here is a look at the Koreatown area where ground malathion spraying will begin Tuesday, after a Medfly was found. About 177 properties will be affected. Officials also urged residents within a 47-square-mile area not to remove home-grown fruits and vegatables, bottom.