Spotted Wing Drosophila Alert and Berry Notes — September 15, 2023

Drosophila Trap
Drosophila Trap, photo by David Handley

David Handley, Vegetable and Small Fruit Specialist; James Dill, Pest Management Specialist, Phil Fanning, Assistant Professor of Agricultural Entomology, Christina Howard, Maine New Farmer Project Manager

Spotted wing drosophila trap counts in the past few weeks have been relatively low for this late in the season and that trend continued this week, with trap catches lower in most locations. Typically, we don’t see significant declines in spotted wing drosophila numbers until we have had a few hard frosts, but so far, populations have not risen at their typical rate nor reached levels of past seasons. However, numbers are still high enough to pose a significant threat to any ripe or ripening berries remaining in the field, so growers should maintain a regular, frequent spray interval to prevent larvae from infesting their fruit.

A 5-7 day spray schedule is recommended to minimize fruit infestation in fields.

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

pumpkin photo for landing page image link for resources by crop
Pumpkins at Highmoor Farm, UMaine Extension photo

Highmoor Farm 2023 Fall Open House October 5, 2023 at 5:00 p.m.
University of Maine Cooperative Extension at Highmoor Farm will be hosting its annual fall tour on Thursday, October 5 at 5:00 p.m. Join us to learn about this year’s research and to share your season’s highlights and challenges.  Trials on tour this year will include artichokes, blueberries, celery, celeriac, strawberries and more than 20 varieties of pumpkins. All are welcome and there is no cost to attend. Highmoor Farm is located at 52 US Route 202 in Monmouth, ME. If you have any questions or require any accommodation to attend, please contact us at 207.933.2100.

Other IPM Web Pages
Michigan State University Spotted Wing Drosophila
Penn State University Spotted Wing Drosophila Overview
University of New Hampshire SWD Weekly IPM Reports

David T. Handley
Vegetable and Small Fruit Specialist

Highmoor Farm
P.O. Box 179
Monmouth, ME 04259

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

Where brand names or company names are used it is for the reader’s information. No endorsement is implied nor is any discrimination intended against other products with similar ingredients. Always consult product labels for rates, application instructions and safety precautions. Users of these products assume all associated risks.

The University of Maine is an equal opportunity/affirmative action institution.

Weekly Spotted Wing Drosophila Trap Captures

Town Spotted Wing Drosophila weekly trap catch 8/4/23 Spotted Wing Drosophila weekly trap catch 8/11/23 Spotted Wing Drosophila trap catch average for 8/14/23 – 8/25/2023 Spotted Wing Drosophila weekly trap catch 9/1/23 Spotted Wing Drosophila weekly trap catch 9/8/23 Spotted Wing Drosophila weekly trap catch 9/15/23
Wells 22 166 600 276 740 125
Limington 2 19 104 65 175 64
New Gloucester 214 280 840 400 316 178
Mechanic Falls 20 34 976 1,029 500 65
Bowdoinham 42 138 624 158 270 296
Monmouth (unsprayed plot) 43 114 1,408 168 119 46
Wayne 8 1,012 1,012 696 98