Spotted wing drosophila also a backyard pest

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For the last few years, farmers in coastal California have been dealing with a new pest, spotted wing drosophila. Yesterday, the Contra Costa Times reported that it is becoming a problem in backyards, too.

A native of Asia, spotted wing drosophila made its first American appearance in August 2008 and is now widespread throughout California's coastal counties. Cherries, raspberries, blackberries, blueberries, strawberries, plums and nectarines are all favorites of the pest.

According to the Times, the Solano County agricultural commissioner is asking residents to help slow the spread of the pest by disposing of infested fruit on backyard trees and on the ground.The fruit should be placed in a sturdy, sealed plastic bag and put in the trash.

"These efforts will help reduce the overwintering populations that might infest next year's crops or later ripening varieties," the story quoted Carolyn DeBuse, orchard systems farm advisor with UC Cooperative Extension in Solano County.

Spotted wing drosophila lay eggs beneath the skin of the fruit, and after a few days, the eggs hatch. As the larvae develop, a soft area that looks like a bruise appears, but there is no visible sting.

If consumers inadvertently eat an infested fruit, it poses no health concerns. For more information on the spotted wing drosophila, see the IPM pest note on the new pest.

A typical bruise caused by spotted wing drosophilia larvae.