Spotted Wing Drosophila Update: November 4, 2016

Click on photo to enlarge.

David Handley, Vegetable and Small Fruit Specialist; James Dill, Pest Management Specialist; Frank Drummond, Professor of Insect Ecology/Entomology

Spotted Wing Drosophila Trap Catch
Spotted Wing Drosophila Trap Catch; photo by Christina Hillier

Warmer temperatures and some rain have resulted in an upsurge of spotted wing drosophila trap catches in some locations, while numbers continued a downward trend in others. Once the weather settles into a colder pattern, we expect fly populations will decline rapidly, based on our experience in previous years. Our monitoring sites are done harvesting for the season, and we have removed our traps from the fields. If you still have any fields or high tunnels being harvested, drosophila pose a significant threat to any remaining fruit. A 5 to 7 day spray interval is recommended to prevent infestations of larvae. See the New England Small Fruit Management Guide for pesticide options.

We’d like to thank the farmers who allowed us to set up traps in their fields and share the data with you. Thanks also to our scouts, Lindsey Ridlon, Shannon Buzzell, Hannah Kerrigan, Danielle Murray, and Pat McManus. Special thanks to Christina Hillier for counting all those flies!

Town Spotted Wing Drosophila
weekly trap catch
Spotted Wing Drosophila
weekly trap catch
Spotted Wing Drosophila
weekly trap catch
Limington* 303 301 1,077
Limerick 2,832 1,722 11,472
Wells 677 539 171
Cape Elizabeth 1,976 1,384 347
Bowdoinham 198 132 390
Dresden 4,264 431 2,992
Freeport 109 132 11
Poland Spring 3,336 1,066 442
Mechanic Falls 136 138 104
Monmouth* 4,312 625 232
Wales 176 134 298
Wayne 9,880 5,472 9,592
Farmington 2,376 1,712 968
*unsprayed planting

David T. Handley
Vegetable and Small Fruit Specialist

Highmoor Farm, P.O. Box 179, 52 US Route 202, Monmouth, ME 04259, 207.933.2100

UMaine Extension Diagnostic Research Lab, Pest Management Unit, 17 Godfrey Drive, Orono, ME 04473, 1.800.287.0279

For more information on identifying spotted wing drosophila (SWD) and updates on populations in Maine, visit our SWD blog.

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