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New fruit fly prompts grower alert

The Sunshine Coast Regional District (SCRD) is being asked to spread the word about a new fruit fly that can cause serious damage to berries and other soft fruit crops.

The Sunshine Coast Regional District (SCRD) is being asked to spread the word about a new fruit fly that can cause serious damage to berries and other soft fruit crops.

"It's on the Coast now and I'm not sure that gardeners and growers are aware of it," Verity Goodier told directors at last week's planning and development committee meeting.

Unlike other fruit flies that infest overripe or fallen fruit, spotted wing drosophila females lay eggs in healthy fruit, contaminating it with larvae.

Native to Southeast Asia, spotted wing drosophila has spread rapidly through Europe and was first detected in the U.S. in 2008 and in B.C. the following year. It is now widespread in coastal and Interior fruit-growing areas.

"This is a potential threat to growers - blueberry, raspberry - and, of course, home gardeners too," Goodier said. "It's going to be here forever. We're going to have to live with it."

Goodier, who is affiliated with the Sunshine Coast Botanical Garden Society, but was appearing as a private citizen, asked the SCRD to set up a public information meeting and pay the travel expenses for two experts from Powell River who are willing to give a presentation on the new pest.

Directors were open to the idea and Goodier was asked to submit a funding application.

Roberts Creek director Donna Shugar said the request was timely, as a large berry farm is under development in West Howe Sound on Agricultural Reserve Land, and West Howe Sound director Lee Turnbull said, "To me, this is an emergency."

A "pest alert" updated last fall by the B.C. Ministry of Agriculture said spotted wing drosophila has been confirmed infesting wild and cultivated raspberry and blackberry, strawberry, cherry, peach, nectarine, apricot and plum, and is suspected in hardy kiwi fruit.

Wild hosts confirmed in B.C.'s coastal regions include Oregon grape, elderberry, currant, dogwood, mulberry, salmonberry, thimbleberry, salal, Indian plum, wild cherry and red huckleberry.

The flies are two to three millimetres long, brownish with red eyes and clear wings. Males have a black or grey spot on the end of each wing and two black bands on the front legs. Females do not have spots or leg bands but have saw-like ovipositors that cut into the fruit skin.

To manage the pest, the Ministry release recommended "good harvest and sanitation practices, such as culling soft fruit, destroying culls and keeping processing areas and equipment free of old fruit."

It also listed five pesticides approved last year to control the flies, including two - Entrust (spinosad) and Pyganic (pyrethrins) - that are described as acceptable for organic crop production.

The flies can be monitored with apple cider vinegar baited cup-traps.

For more information, see www.agf.gov.bc.ca/cropprot/swd.htm.