Spotted Wing Drosophila Alert: October 20, 2017

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

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

Trap counts of spotted wing drosophila rose dramatically in some locations over the past week. We are now finding fly numbers in the thousands at more than half of our trapping sites. (See table below.) All sites remain well over the threshold for larvae infestation if susceptible crops are not protected with regular sprays or netting. A spray interval of every 5 to 7 days should be adequate to prevent any marketable fruit remaining in the field from becoming infested. Continue harvest regularly and often, and keep overripe and rotten fruit out of the field as much as possible. Long range weather forecasts suggest continued warmer than normal temperatures ahead, which will both extend the late berry season and likely keep spotted wing drosophila pressure high.

Spotted Wing Drosophila Larvae in Raspberry
Spotted Wing Drosophila Larvae in Raspberry; photo by David Handley

For more information on identifying spotted wing drosophila and updates on populations around the state, visit our SWD blog.

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

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Town Spotted Wing Drosophila weekly trap catch 10/6/17 Spotted Wing Drosophila weekly trap catch 10/13/17 Spotted Wing Drosophila weekly trap catch 10/20/17
Wells 567 88 8664
Limington 87 152 3488
Limerick 1808 187 637
Cape Elizabeth 124 750 2424
New Gloucester 209 408 1272
Bowdoinham 563 244 1584
Dresden 4376 2816 3368
Freeport 133 655 407
Poland Spring 440 294 3504
Mechanic Falls 55 31 546
Monmouth 4696 1188 3368
Wales 343 372 325
Farmington 7568 5680 5112