State Expects to Easily Swat New Fruit Fly

Traps turned up no additional guava fruit flies in Orange County on Tuesday, raising hopes among state agriculture officials that the crop-threatening insects, never before seen in the Western Hemisphere, may be few and easily destroyed.

“It’s encouraging. It probably means we have a very small infestation,” said Brian Taylor, a state entomologist. “Other than that, we’re just going to keep our fingers crossed.”

The first of the guava fruit flies, or Dacus correctus, was found last Wednesday in Garden Grove in one of the thousands of insect traps maintained by the state since the massive Mediterranean fruit fly infestation of the early 1980s.

Its discovery prompted the state to set additional traps nearby; those snared two more flies in Westminster and Midway City on Saturday. More traps were set over 81 square miles around Westminster, the last of them Tuesday.

Taylor said that even if no more fruit flies are trapped, an eradication program will begin in a 16-square-mile area centered in Westminster. It is expected to start once the federal Environmental Protection Agency issues a special permit, presumably by week’s end.

No Approved Insecticide

A permit is required because federal law allows use of insecticides only against species for which they are specifically approved. Since the guava fruit fly, a native of Asia and India, has never been seen before in California, no insecticide has been earmarked by the EPA for use against it.

Don Henry, chief of the state Department of Food and Agriculture’s emergency projects branch, said the guava fruit fly will be dealt with exactly as previous infestations of the similar Oriental fruit fly.

A chemical lure called methyl eugenol, which is particularly attractive to the guava fruit fly, will be combined with an insecticide known as Dibrom or Naled, which is commonly sold over the counter and used in some flea and tick collars for pets. The resulting paste kills the insects through contact.

Henry said small blobs of the paste will be squirted high on utility poles and tree trunks beyond the reach of people and pets.

‘Presents No Hazard’

“In the manner it is to be used--very, very low concentrations in very small amounts to scattered objects--it presents no hazard,” said Dr. Peter Kurtz, senior medical coordinator for the state agriculture department.

Taylor said the insecticide will be applied every other week for eight weeks after the last fly is trapped. Then traps will be checked daily for four to six more months, he said.

State officials said they suspect the guava fruit flies made their way into California as larvae in exotic fruit mailed from Hawaii or Asia. A week before the flies were found, such fruit infested with other, equally destructive fruit-fly species was discovered in packages in a Santa Ana mail sorting office.

Agriculture officials suspect that the Mediterranean fruit fly infestation of 1980 to 1982, which cost $100 million to eradicated, was started by such illegal shipments.