Pest management


Staying on top of the


SWD threat


Growers advised to keep doing their part because SpottedWing Drosophila isn’t about to go away. By Judie Steeves


W


ith amildwinter in theOkanagan-Similkameen, traps put out for SpottedWingDrosophila detected their presence as early this year as last year, inmid-


May, long before fruitwas ripening, reports agriculture ministry entomologist Susanna Acheampong. Scientists have not been able to determinewhat they feed on


that early in the season, before evenwild hosts are fruiting, she said. “We’re trying to figure that out.” Theywere also being detected inMay inWashington State. “Growers did a good job last year of controlling them. There


was little damage last year.” Obviously, it’s a newpest that’s here to stay, so growers


must continue to be vigilant, trap to knowwhen populations are growing, and apply controlswhen recommended. Area-widemonitoring is ongoingwithmore than 100 traps


placed throughout the valley through the packinghouse and dozensmoremonitored by theministry and by consultants, she said.However, growers also should trap so they know when the tiny fly is around, aswell as practice good sanitation in the field, ensuring there is no ripening fruit left thatmay provide a host for them. In thewild, Acheampong said, no SWDhas been found in


saskatoon berries, but they do infestOregon grape aswell as pin cherries, blackberries, blue elderberry,mountain ash,wild rose hips and nightshade. As soft fruit such as cherries nearmaturity, you can be sure


theywill be around, but she said there are even two products nowregistered for use by organic growers, so all growers have the tools to control the pest. SWDis a vinegar fly native to Asiawhichwas first detected


in this region in 2009 and has since established itself and proven to be a pest of commercial berry crops aswell as soft fruit grown in theOkanagan, Similkameen and Creston areas. Even apples that are damaged can become a host for SWD. Growth of populations each season is dependent on temperatures,withmore-rapid growth during hotweather.


24 British Columbia FRUIT GROWER • Summer 2013


Provincial agriculture ministry


entomologist Susanna


Acheampong. Researchwork is underway into the possibility of rearing


parasitoids of SWDto control populations but as yet it is incomplete. It is important to harvest fruit early rather than late to


prevent the spread of SWDto later-maturing crops, and to collect all fruit, including fallen fruit to eliminate potential host material and prevent increased populations. Be sure to dispose of infested fruit by bagging it securely and


leaving it in the sun for aweek or bury it at least a foot deep. Spray timing of fruit is critical. For detailed information about SWDand up-to-date


information on registered products for control, go to the ministrywebsite at:www.agf.gov.bc.ca/cropprot/swd.pdf


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36