Another Medfly Found in Rosemead; New Round of Spraying Called Essential

Agricultural officials reported today that another Mediterranean fruit fly has been trapped in Rosemead, raising the possibility that a new round of pesticide spraying will be needed--just two months after the pest supposedly was eradicated from the city.

The discovery was made in the most heavily sprayed sector of Southern California’s year-old infestation, and it reinforced fears that the state’s aggressive campaign of aerial malathion spraying might not be working.

Some of the state’s scientific advisers said the discovery, which was made within three blocks of where another Medfly was found last week, was a distressing sign that the pest might be on the verge of a summer population explosion. They fear it could engulf the region just as it did last July when the first of 273 Medflies was found near Elysian Park.

James R. Carey, one of five members of the state’s Medfly science advisory panel, said that over the past 15 years the vast majority of Medflies have been trapped in California in August, September and October when the warm temperatures and the abundance of ripe fruit offer ideal breeding conditions for the pest.

“We’re only in the foothills,” Carey said today. “The peak is in September and October. It’s very possible this could grow as large as before.”

Carey and the other four members of the state’s advisory panel that oversees the eradication effort were convened today for a telephone conference to discuss a new battle plan to combat the pest.

State officials said they will announce a formal decision Thursday on whether to spray Rosemead. They also want to begin spraying a 14-square-mile sector of downtown Los Angeles on Thursday night, but earlier in the day a judge will hear the city’s claim that the pesticide application is unsafe and should not be allowed.

Carey said he believes there is no question that spraying for Rosemead must begin.

“They’ll have to pull the trigger now,” Carey said. “This is the beginning of round two.”

The single mated female Medfly was found in a nectarine tree at a home in the 3800 block of Brookline Avenue--three blocks away from where another mated female Medfly was found last week.

The first Medfly would usually have prompted an immediate order for spraying, but a decision was delayed because scientists were unable to make a complete identification of the specimen.