Action Targets Oriental Fruit Fly

State agricultural officials have placed a quarantine on the movement of fruit and vegetables in southeastern San Diego County after trapping 10 Oriental fruit flies in the area.

Imposed Monday, the restrictions cover a 60-square-mile swath that includes the South Bay Terraces neighborhood of San Diego and the unincorporated community of La Presa. The state is also starting a treatment program, said Larry Cooper, a spokesman for the state Department of Food and Agriculture.

A gum mixture containing a female pheromone and a tiny amount of pesticide will be squirted onto poles and trees at a height of eight feet. Male Oriental flies, attracted to the gum by the pheromone, eat the chemical mixture and die. The treatment, known as male annihilation, has proved nearly 100% effective, Cooper said.

The insects attack more than 250 kinds of fruits and vegetables, including avocados, tomatoes, citrus fruit, guavas and apples.

The quarantined area contains no commercial growers but dozens of nurseries, which must take steps to ensure that the fruit trees they sell are not infested.

Homeowners are barred from transporting backyard fruit and vegetables outside the area.

Cooper said infestations of the Oriental fruit fly occur several times a year in California but have never reached the magnitude of those of the Mediterranean fruit fly, which has posed a major threat to crops.

As its name suggests, the Oriental fruit fly is not native to California or the United States. It enters the country on fruit from Asia, where it is a major problem in the Philippines, India and Thailand.

The state agriculture department maintains a trapping program to detect fruit fly outbreaks. So far this year, about 90 Oriental fruit flies have been found in Southern California.