County agricultural officials reported Monday that they had trapped an Oriental fruit fly and four gypsy moths in recent days but said that they had no immediate plans for aerial spraying to eradicate the pests.
Without the discovery of other Oriental fruit flies, the discovery of just one, found July 3 in La Mesa, does not warrant the sort of spraying administered in May and June over El Cajon to combat the Mexican fruit fly, assistant agricultural commissioner Bill Snodgrass said.
Even if other Oriental flies are found, the county would be much more likely to put out baited traps than to spray, because it's a better plan for that kind of fly, Snodgrass said.
The moths, "voracious eaters" of trees and shrubs but no threat to valuable citrus crops, have been found in La Mesa and in Vista, Snodgrass said. If more are found, he said, agricultural officials intend only to set traps.
The sole Oriental fly, a sexually mature male, was found in a trap set in an orange tree, Snodgrass said. It was the first Oriental fly found in San Diego County since 1987 and prompted officials to set more traps to see if there are additional sexually mature flies buzzing about, he said.
Oriental fruit flies, predominantly yellow with dark markings, deposit eggs under the skin of 150 kinds of fruit, including citrus.
In 1987, when three Oriental flies were found, the county successfully used the baited traps, which are lined with a chemical that attracts the flies to a lurking insecticide, Snodgrass said.
Of the four moths, with which the county is "not nearly as concerned about," three were found in La Mesa and one in Vista, Snodgrass said. Trapping in the immediate areas around each find has been increased, he said.