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2013 Spotted Wing Drosophila Summary for Maine Berry Growers

2013 Spotted Wing Drosophila Summary for Maine Berry Growers

David Handley, Vegetable & Small Fruit Specialist
James Dill, Pest Management Specialist

The spotted wing drosophila (Drosophila suzukii) is an insect invasive to Maine that was first captured here in the fall of 2011.  Based on crop damage in other parts of the country and our own experience in 2012, we know that this insect poses a serious threat to most of the soft fruit crops we grow here, including raspberry, blackberry, blueberry and strawberry. During the summer of 2013 the University of Maine Cooperative Extension Pest Management Program set up drosophila traps in berry fields around the southern, central and coastal regions of the state to monitor the presence and activity of this insect.

The traps were 16 oz. red plastic cups with 30, 1/8” holes punched under the rim to allow the flies access.  A 1/2” wide band of black was painted just under the rim of the cup to increase its visual attractiveness.  The cups were topped with a tight fitting plastic lid and mounted on 4’ tomato stakes fitted with 4” hose clamps to act as a cup holder.  Four to six ounces of bait/killing solution (a mixture of cider vinegar and alcohol) was poured into each trap. A 60 ml plastic specimen cup containing a second bait consisting of water, sugar, flour and yeast was then placed within the trap to further increase its attractiveness.    We placed traps either within the crops or in a wooded area near the crops, knowing the insect prefers humid, shaded areas.   We emptied the traps weekly and restocked them with fresh bait.  The insects captured in the traps were brought back to our lab at Highmoor Farm in Monmouth to be identified.  Many different species are attracted to these traps and proper identification, while time consuming, is essential.  As populations increased we informed growers through our IPM newsletter, blog and webpage, hoping to keep the pest as well managed as possible throughout the summer.

In 2013, the first spotted wing drosophila were caught in Warren and Wells on July 19. With the exception of trapping sites in Warren and Bowdoinham, captures were very low, just a few flies per trap, and scattered, most sites having no flies, until the third week of August.   At that point we began catching low numbers of flies at nearly all locations, including Wells, Limington, Limerick, Springvale, Cape Elizabeth, New Gloucester, Poland Spring, Mechanic Falls, Wales, Livermore, Bowdoinham, and Dresden. Traps in wild blueberry fields in Hancock and Washington counties were also catching flies at this point, but also in low numbers.  By the end of August, our Monmouth, Farmington and Oxford sites had also captured flies.  Trap captures generally remained low (0 to 20 flies/trap) with occasional small flare ups (20 to 100 flies/trap) until the first week of September.  At that point numbers rose fairly consistently in nearly all locations, with weekly trap counts ranging from just a few flies to nearly 1,000. Raspberry and blueberry fruit infested with the small white larvae were being reported.  The highest numbers of flies continued to be found in the most southern and coastal sites.  By the end of October many sites were catching flies well into the thousands (14,000 during one week in Limerick) while some caught only a few flies. At this point flies were readily visible around ripe fruit in many fields and larvae were found infesting most of the fruit in any plantings that had not been sprayed.   At the end of the season we found that a trap maintained for us by a grower in Caribou had caught three flies.

Similar to the 2012 season, growers using insecticides to control spotted wing drosophila found that weekly sprays appeared to provide adequate control when populations remained relatively low (0-10 flies/per week). However, as fly populations expanded, growers found that twice weekly sprays were needed to keep larvae out of the fruit.  Growers used Entrust®, Delegate®, Brigade®, Bifenthrin®, Hero®, Mustang Max®, and/or malathion insecticides, and most found that these products usually offered adequate control if applied on a frequent basis.  Growers who did not apply pesticides saw near total crop loss, following the arrival of spotted wing drosophila in their fields.

Spotted Wing Drosophila Trap Captures 2013 (Excel)

Spotted wing drosophila trap catches remained relatively high throughout the remainder of the season, with dips in late September and early November, which may correlate with dry periods. As in 2012, the highest trap catches occurred late in the season, well after most of the crops had been harvested or lost to frost.  The lack of food likely make the traps more attractive, at least partially accounting for the increased catch, but this reiterates that high numbers of flies survive long after killing frosts have occurred.   By the end of November, populations finally dropped significantly, suggesting that the flies were now entering the over-wintering stage.

Spotted wing drosophila overwinter as adults (flies).  Any time the air temperatures exceed 45ºF for more than a few hours, it is likely that some adults will start becoming active.  The winter of 2013-14 has been one of the coldest in recent memory, and it will be interesting to see how well the flies come through it.  However, it would be unwise to assume that we will not be seeing many flies this summer because of the cold winter.  In its native Asia, it survives cold winters well.  Additionally, any storm fronts moving into Maine from the south could carry with it flies from southern states where the winter has not been so harsh.   Thus, berry growers should anticipate needing to manage drosophila for the 2014 season.  Based on our 2012 and 2013 experience, we believe it will be unlikely to significantly infest crops until relatively late in the season when populations reach damaging levels (late August in 2013 at some sites). Therefore, earlier ripening crops such as June-bearing strawberries should not be significantly impacted; but later ripening crops such as fall fruiting raspberries, late ripening varieties of blueberries and fall strawberries will need to be protected as soon as fruit begin to ripen.  We plan to monitor drosophila populations in Maine again in 2014, and carry out research on improving our trapping strategies to provide an early warning system in the future.

Based on what we know so far about this pest, here are six rules for managing spotted wing drosophila.

  1. Monitor for the flies with traps, and for the larvae in fruit.
  2. Spray regularly and often once flies have been found in the field (1-2/week).
  3. Harvest fruit regularly and often; do not leave any ripe/rotten fruit in the field.
  4. Sort fruit at harvest; do not leave any soft fruit in the container to be sold.
  5. Chill all fruit immediately after harvest to 38ºF (or as close as you can) for at least 12 hours to slow development of any eggs or larvae.
  6. Prune the planting to open up the canopy and create dry, light conditions.

Please follow our blog providing regular updates of spotted wing drosophila trapping data and management strategies during the growing season, where you can sign up for notifications of updates.

David T. Handley
Vegetable & Small Fruit Specialist

Highmoor Farm                       Pest Management Office
P.O. Box 179                             491 College Ave
Monmouth, ME  04259        Orono, ME  04473
207.933.2100                          1.800.287.0279

 

IPM Web Pages:

http://extension.umaine.edu/ipm/
http://www.pestwatch.psu.edu/
http://www.umass.edu/umext/ipm/

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.

Image Description: drosophila trap

Image Description: Spotted Wing Drosophila Trap Captures 2013

Fruit Growers Alert 9/30/13: Spotted Wing Drosophila Counts Remain at High Levels

Fruit Growers Alert – September 30, 2013

For full page print version, please see link at the bottom. Click on photos to enlarge.

SPOTTED WING DROSOPHILA COUNTS REMAIN AT HIGH LEVELS

We continue to capture spotted wing drosophila flies at all of our monitoring sites from southern, mid-state and coastal Maine. While counts have dropped in some locations over the past week, levels are still high enough to infest any unprotected berries still remaining in the field. Highest counts have been at the coastal sites and lowest counts have been in the more northern and western sites. Our experience has shown that the flies will survive through repeated frosts and continue to infest fruit well into the fall. Therefore, any farms that still have late ripening raspberries, blackberries, blueberries, grapes or day neutral strawberries should continue to protect their crops with an approved insecticide. In some locations a 7-day spray interval may be adequate to prevent infestation, but areas with high fly populations may still require a 4 to 5-day spray schedule.

Recommended insecticide products that provide good control of drosophila on berries include Delegate®, Brigade®, Bifenture®, Danitol®, Mustang Max®, malathion and Assail®. Effectiveness of these products can range from three to seven days.  Please check product labels for rates, post-harvest intervals and safety precautions.

Four Rules for Managing Spotted Wing Drosophila:

  1. Spray ripening fruit regularly with an approved insecticide (every 5-7 days).
  2. Harvest crop frequently and regularly; remove all ripe and rotten fruit from the field.
  3. Chill all harvested fruit immediately to as close to 33º F as soon as possible; hold in refrigeration until ready to sell.
  4. Open up the planting through pruning and spacing to improve light and air penetration and reduce moisture and humidity within the plant canopy.

David T. Handley
Vegetable and Small Fruit Specialist

Highmoor Farm                       Pest Management Office
P.O. Box 179                             491 College Avenue
Monmouth, ME  04259        Orono, ME  04473
207.933.2100                          1.800.287.0279

IPM Web Pages:
http://extension.umaine.edu/ipm/
http://www.pestwatch.psu.edu/sweet_corn.htm
http://www.umass.edu/umext/ipm/

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.

Image Description: Spotted Wing Drosophila Larva in Blackberry

Image Description: Spotted Wing Drosophila Maggot in Raspberry

Fruit Growers Alert 8/30/13: Spotted Wing Drosophila Continues to Spread

Fruit Growers Alert – August 30, 2013

For full page print version, please see link at the bottom. Click on photos to enlarge.

SPOTTED WING DROSOPHILA CONTINUES TO SPREAD

All sites that we are monitoring in southern and coastal Maine now have spotted wing drosophila flies and fly counts have increased at some sites this week.  We also have more reports from growers of larvae in fruit, indicating that that even low trap captures signal a significant threat.  Spotted wing drosophila (SWD) flies were captured in traps in Wells, Cape Elizabeth, Limington, Springvale, New Gloucester, Gray, Mechanic Falls, Monmouth, Wales, Livermore Falls, Farmington, Oxford, Bowdoinham, Dresden, Warren, Stillwater and Levant.  Trap captures continue to be very variable, ranging from just one fly to nearly 200, with most still catching fewer than 100 per week.  The coastal sites tend to have more flies than any other locations, but counts have been up and down from week to week at many sites. We expect fly populations to rise further in the coming days and weeks.  If you haven’t yet done so, we recommend that growers set up their own traps to monitor for SWD, and learn to distinguish it from other species that will get into the trap.  We recommend that all ripening fruit be protected with an approved insecticide. Regular and repeated treatments are needed to keep fruit from becoming infested. In some locations a 7-day spray interval has not been adequate to prevent infestation, so we have tightened the spray schedule to every 4 to 5 days. Chilling fruit to as close to 32ºF immediately after harvest can significantly reduce the activity and emergence of any larvae.  Keeping the fields clean of over-ripe and rotten fruit can also help reduce the incidence of this insect.

Raspberries before and after infestation, 48 hours at room temperature after picked.

Recommended insecticide products that provide good control of drosophila on berries include Delegate®, Brigade®, Bifenture®, Danitol®, Mustang Max®, malathion and Assail®.  Effectiveness of these products can range from three to seven days.  Please check product labels for rates, post-harvest intervals and safety precautions.

David T. Handley
Vegetable & Small Fruit Specialist

Highmoor Farm                       Pest Management Office
P.O. Box 179                             491 College Avenue
Monmouth, ME  04259        Orono, ME  04473
207.933.2100                          1.800.287.0279

IPM Web Pages:
http://extension.umaine.edu/ipm/
http://www.pestwatch.psu.edu/sweet_corn.htm
http://www.umass.edu/umext/ipm/

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.

Image Description: Fall Raspberries

Image Description: Spotted Wing Drosophila Emerging from Fall Raspberries

Fruit Growers Alert 8/16/13: Spotted Wing Drosophila Spreading, Counts Increasing

Fruit Growers Alert – August 16, 2013

For full page print version, please see link at the bottom. Click on photos to enlarge.

SPOTTED WING DROSOPHILA SPREADING, COUNTS INCREASING

Spotted wing drosophila (SWD) flies were captured in traps in Bowdoinham, Cape Elizabeth, Dresden, Gray, Limington, Livermore Falls, Mechanic Falls, Monmouth, New Gloucester, Springvale, Wales, Warren and Wells.  Trap captures varied this week from just one fly to over 100, with most catching fewer than 10.  There are now just a few sites where we haven’t yet caught any flies.   The Bowdoinham site again had far more flies than any other location (135) although this was only about ½ the number we caught at the same location last week. The other sites with higher numbers were Wells (21) and Wales (18).  Some of this variation may just be a matter of where the traps are placed at each site.  Ideally, growers should set up their own traps to monitor for SWD, and learn to distinguish it from other species that will get into the trap.

While there is no valid threshold for spotted wing drosophila in berry fields (most buyers have zero tolerance), growers should initiate a regular insecticide spray program once SWD is captured in your area and you have ripe or nearly ripe fruit in your fields. Recommended insecticide   products that provide good control of drosophila on berries include Delegate®, Brigade®, Bifenture®, Danitol®, Mustang Max®, malathion and Assail®.  Effectiveness of these products can range from three to seven days.  Repeated applications throughout the harvest season may be required to prevent larvae from infesting the fruit.  Please check product labels for rates, post-harvest intervals and safety precautions. Keeping the fields clean of over-ripe and rotten fruit can also help reduce the incidence of this insect.

David T. Handley
Vegetable & Small Fruit Specialist

Highmoor Farm                       Pest Management Office
P.O. Box 179                             491 College Avenue
Monmouth, ME  04259        Orono, ME  04473
207.933.2100                          1.800.287.0279

IPM Web Pages:
http://extension.umaine.edu/ipm/
http://www.pestwatch.psu.edu/sweet_corn.htm
http://www.umass.edu/umext/ipm/

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.

Image Description: Spotted Wing Drosophila Trap

Image Description: Male and Female Spotted Wing Drosophila

Fruit Growers Alert 8/9/13: Spotted Wing Drosophila Populations Jump in Coastal Site

Fruit Growers alert – August 9, 2013

For full page print version, please see link at the bottom. Click on photos to enlarge.

SPOTTED WING DROSOPHILA POPULATIONS JUMP IN COASTAL SITE

Spotted wing drosophila (SWD) flies were captured in traps in Wells, Cape Elizabeth, Limington, New Gloucester, Gray, Monmouth, Bowdoinham and Corinna. Most traps had one to three flies in them, and there are still a few locations where we have not caught any flies. The exception was the Bowdoinham site, which had over 200 flies for the week. We had no data from our Dresden site, which is close by, this week (broken trap) but the count was higher there last week as well.

There have been more reports of maggots in blueberry fruit this week, but these are the larvae of was blueberry fruit fly (aka blueberry maggot), not spotted wing drosophila, as we reported last week. Blueberry maggot populations of this insect have been very high this season, and any plantings that were not sprayed as fruit began to ripen are susceptible to infestation. For a good fact sheet on this pest visit our web site. If you are finding larvae in harvested blueberry fruit, there is a fact sheet from North Carolina State University website to help identify which insect is causing the problem.

There is no valid threshold for spotted wing drosophila in berry fields. If SWD has been captured in your area and you have ripe or nearly ripe fruit in your fields, the crop should be protected with a recommended insecticide. Products that provide good control of drosophila on berries include Delegate®, Brigade®, Bifenture®, Danitol®, Mustang Max®, malathion and Assail®. Effectiveness of these products can range from three to seven days. Repeated applications throughout the harvest season may be required to prevent larvae from infesting the fruit. Please check product labels for rates, post-harvest intervals and safety precautions. Keeping the fields clean of over-ripe and rotten fruit can also help reduce the incidence of this insect.

David T. Handley
Vegetable & Small Fruit Specialist

Highmoor Farm                       Pest Management Office
P.O. Box 179                             491 College Avenue
Monmouth, ME  04259        Orono, ME  04473
207.933.2100                          1.800.287.0279

IPM Web Pages:
http://extension.umaine.edu/ipm/
http://www.pestwatch.psu.edu/sweet_corn.htm
http://www.umass.edu/umext/ipm/

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.

Image Description: Spotted Wing Drosophila Larva in Blackberry

Image Description: Spotted Wing Drosophila Maggot in Raspberry

Fruit Growers Alert 8/2/13: Spotted Wing Drosophila Populations Remain Low

Fruit Growers Alert – August 2, 2013

For full page print version, please see link at the bottom. Click on photo to enlarge.

SPOTTED WING DROSOPHILA POPULATIONS REMAIN LOW

Spotted wing drosophila (SWD) flies were captured in traps in Wells, Dresden, New Gloucester and Bowdoinham this week. Trap captures continue to be fairly low, with many locations not yet recording any flies.  We’re still seeing higher numbers near the coast and in the south, with nine flies caught in Dresden, six in New Gloucester and three in both Wells and Bowdoinham.

We have had several reports of maggots in blueberry fruit this week, but in each case the pest was blueberry fruit fly (aka blueberry maggot), not spotted wing drosophila.  Blueberry maggot is a common pest of blueberries in Maine and populations of this insect have been very high this season, according to Frank Drummond, Professor of Entomology at the University of Maine.

For a good fact sheet on this pest, visit our web site. If you are finding larvae in harvested blueberry fruit, there is a fact sheet on the North Carolina State University website to help identify which insect is causing the problem.

There is no valid threshold for spotted wing drosophila in berry fields.  At this point we believe that if any SWD have been captured in your area and you have ripe or nearly ripe fruit in your fields, the crop should be protected with a recommended insecticide.

Spotted wing drosophila poses the greatest threat to raspberries, blackberries, blueberries and other soft fruit that is beginning to ripen (elderberries, peaches, nectarines, etc.). Products that provide good control of drosophila on berries include Delegate®, Brigade®, Bifenture®, Danitol®, Mustang Max®, malathion and Assail®. Research carried out at the Connecticut Agricultural Experiment Station suggests that adding table sugar to group 4A insecticides such as Assail®, may improve their effectiveness. The recommended rate would be 1-2 lbs. sugar per 100 gallons of spray. Effectiveness of these products can range from three to seven days.  Repeated applications throughout the harvest season will likely be required to prevent larvae from infesting the fruit.  Please check product labels for rates, post-harvest intervals and safety precautions. Keeping the fields clean of over-ripe and rotten fruit can also help reduce the incidence of this insect.

For information on identifying spotted wing drosophila and making your own monitoring traps, visit the Michigan State University’s Spotted Wing Drosophila website.  There is also a good fact sheet series on Management of Spotted Wing Drosophila from Penn State on their website.

David T. Handley
Vegetable & Small Fruit Specialist

Highmoor Farm                       Pest Management Office
P.O. Box 179                             491 College Avenue
Monmouth, ME  04259        Orono, ME  04473
207.933.2100                          1.800.287.0279

IPM Web Pages:
http://extension.umaine.edu/ipm/
http://www.pestwatch.psu.edu/sweet_corn.htm
http://www.umass.edu/umext/ipm/

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.

Image Description: Spotted Wing Drosophila Trap with One Male SWD Circled

Fruit Growers Alert 7/26/13: Spotted Wing Drosophila Activity Spreading

Fruit Growers Alert – July 26, 2013

For full page print version, please see link at the bottom. Click on photos to enlarge.

SPOTTED WING DROSOPHILA ACTIVITY SPREADING

Spotted wing drosophila (SWD) flies were captured in traps in Wells, Warren, Dresden, New Gloucester, Monmouth, Union and Lincolnville this week. These trap captures indicate that SWD has become active in more regions of the state. Most trap captures have been very low to date (1 to 3 flies), but some sites near the coast have seen higher numbers this week. A trap in Dresden caught seven flies. One trap in Warren caught 13 flies while another caught 84.  SWD populations are also rising in the other New England states this week, according to reports from Massachusetts, New Hampshire and Connecticut.

There is no valid threshold for spotted wing drosophila in berry fields. At this point we believe that if any SWD have been captured in your area and you have ripe or nearly ripe fruit in your fields, the crop should be protected with a recommended insecticide.

Spotted wing drosophila poses the greatest threat to raspberries, blackberries, blueberries and other soft fruit that is beginning to ripen (elderberries, peaches nectarines, etc.). Products that provide good control of drosophila on berries include Delegate®, Brigade®, Bifenture®, Danitol®, Mustang Max®, malathion and Assail®. Research carried out at the Connecticut Agricultural Experiment Station suggests that adding table sugar to group 4A insecticides such as Assail®, may improve their effectiveness. The recommended rate would be 1-2 lb. sugar per 100 gallons of spray. Effectiveness of these products can range from three to seven days. Repeated applications throughout the harvest season will likely be required to prevent larvae from infesting the fruit. Please check product labels for rates, post-harvest intervals and safety precautions. Keeping the fields clean of over-ripe and rotten fruit can also help reduce the incidence of this insect.

For information on identifying spotted wing drosophila and making your own monitoring traps, visit the Michigan State University’s Spotted Wing Drosophila website. There is also a good fact sheet series on Management of Spotted Wing Drosophila from Penn State on their website.

Highmoor Farm Fruit and Vegetable Growers Field Day July 31, 2013
Join us for the Highmoor Farm Field Day and Summer Tour to be held on Wednesday, July 31, starting at 9:00 a.m. Please join us for the program, farm tours and lunch. For more information and to register online, visit the Field Day website.

David T. Handley
Vegetable & Small Fruit Specialist

Highmoor Farm                       Pest Management Office
P.O. Box 179                             491 College Avenue
Monmouth, ME  04259        Orono, ME  04473
207.933.2100                          1.800.287.0279

IPM Web Pages:
http://extension.umaine.edu/ipm/
http://www.pestwatch.psu.edu/sweet_corn.htm
http://www.umass.edu/umext/ipm/

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.

Image Description: Spotted Wing Drosophila Trap

Image Description: Male and Female Spotted Wing Drosophila Flies

Fruit Growers Alert 7/19/13: Spotted Wing Drosophila Counts are Rising

Fruit Growers Alert – July 19, 2013

For full page print version, please see link at the bottom. Click on photos to enlarge.

SPOTTED WING DROSOPHILA COUNTS ARE RISING

Spotted wing drosophila flies were captured in traps in Warren (6 males, 3 females) and Wells (2 females) this week in a strawberry field and raspberry field, respectively. These trap captures indicate that this insect is becoming more active in Maine. Last week we had low numbers caught in wild blueberry fields in Winterport, Whitefield and Dresden. Although the numbers are still quite low, and don’t pose an immediate threat to berry crops, populations are expected to increase in the coming weeks to damaging levels.  Research and Extension staff in Connecticut, Massachusetts, New Hampshire and New York are all reporting increasing numbers of spotted wing drosophila in traps over the past week, and one grower in Massachusetts claims to have found larvae in recently harvested fruit, although this is unconfirmed.

At this point in the season, spotted wing drosophila will pose the greatest threat to raspberries, blueberries and any other soft fruit that is beginning to ripen. They are able to lay eggs in fruit as soon as it starts to color. Spotted wing drosophila can complete a generation in less than two weeks and, with each adult female laying hundreds of eggs, populations can explode rapidly when conditions are right. Last year populations did not reach damaging levels until late August, but weather conditions can alter how quickly the flies will build up. Frequently repeated insecticide sprays (1 to 3 times per week) may be needed to prevent infestations once the insect is present in a field. Growers should now be on the alert and look for fruit flies on their fruit and symptoms of premature fruit decay. Products that provide good control of drosophila on berries include Delegate®, Brigade®, Bifenture®, Danitol®, Mustang Max®, malathion and Assail®. Research carried out at the Connecticut Agricultural Experiment Station suggests that adding table sugar to group 4A insecticides such as Assail®, may improve their effectiveness. The recommended rate would be 1-2 lbs. sugar per 100 gallons of spray. Please check product labels for rates, post-harvest intervals and safety precautions. Keeping the fields clean of over-ripe and rotten fruit can also help reduce the incidence of this insect. For information on identifying spotted wing drosophila and making your own monitoring traps, visit the Michigan State University’s Spotted Wing Drosophila website.  There is also a good fact sheet series on Management of Spotted Wing Drosophila from Penn State on their website.

Highmoor Farm Field Day
Please join us for the Highmoor Farm Field Day and Summer Tour to be held on Wednesday, July 31, starting at 9:00 a.m. Growers will have an opportunity to tour the fruit and vegetable research plots at the farm, part of the Maine Agricultural and Forest Experiment Station, and hear Extension specialists and guest speakers discuss current research on apples, grapes and vegetables. Maine State Legislators will also be on hand to offer updates on programs and legislation effecting farming in Maine.  Please join us for the program, farm tours and lunch. Visit the Field Day website for more information.

David T. Handley
Vegetable & Small Fruit Specialist

Highmoor Farm                       Pest Management Office
P.O. Box 179                             491 College Avenue
Monmouth, ME  04259         Orono, ME  04473
207.933.2100                          1.800.287.0279

IPM Web Pages:
http://extension.umaine.edu/ipm/
http://www.pestwatch.psu.edu/sweet_corn.htm
http://www.umass.edu/umext/ipm/

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.

Image Description: Spotted Wing Drosophila Larvae in Raspberry

Image Description: Spotted Wing Drosophila Larvae in Blueberry

Fruit Growers Alert 7/9/13: Spotted Wing Drosophila Has Been Found In Maine!

Fruit Growers Alert – July 9, 2013

For full page print version, please see link at the bottom. Click on photos to enlarge.

SPOTTED WING DROSOPHILA HAS BEEN FOUND IN MAINE!

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

Male spotted wing drosophila flies were captured in traps in Dresden and Whitefield on July 3rd in wild blueberry fields. On Saturday, July 6th, a male fly was caught in a Winterport blueberry field. We have traps set out in raspberry and highbush blueberry fields in southern and central Maine, but have not yet captured any spotted wing drosophila in those fields.    However, the presence of spotted wing drosophila in the wild blueberry fields indicates that this insect is now becoming active in the state, slightly earlier than our first captures last year.  Research and Extension staff in Connecticut, Massachusetts, New Hampshire and New York have all reported captures of spotted wing drosophila over the past two weeks, although in all cases the numbers have been low.

Raspberries before and after infestation, 48 hours at room temperature after picked.

Spotted wing drosophila (Drosophila suzukii) is a new pest which is a concern for raspberries blueberries and day neutral strawberries, as well as many other soft fruits.  This insect is a small fruit fly, similar to the type that fly around the over-ripe bananas in your kitchen. However, this species will lay its eggs on fruit before it ripens, resulting in fruit that is contaminated with small white maggots just as it is ready to pick.  As a result, the fruit quickly rots and has no shelf life.  This insect first came into Maine in 2011, and caused significant losses in raspberry and blueberry plantings last year.  Spotted wing drosophila can complete a generation in less than two weeks, with each adult female laying hundreds of eggs, so populations can explode rapidly when conditions are right.  This makes them very difficult to control, and frequently repeated insecticide sprays (1 to 3 times per week) are often needed to prevent infestations once the insect is present in a field.  It appears that spotted winged drosophila can successfully overwinter here, although it has not been able to build up to damaging levels until late summer. June-bearing strawberries and early ripening varieties of raspberries and blueberries may escape infestation, but later ripening varieties and everbearing types of strawberries and raspberries will likely become infested if they are not protected. Now that spotted wing drosophila has been confirmed in Maine, growers should be on the alert and look for fruit flies on their fruit and symptoms of premature fruit decay.   Products that provide good control of drosophila on berries include Delegate®, Brigade®, Bifenture®, Danitol®, Mustang Max®, malathion and Assail®. Research carried out at the Connecticut Agricultural Experiment Station suggests that adding table sugar to group 4A insecticides such as Assail®, may improve their effectiveness. The recommended rate would be 1-2 lb. sugar per 100 gallons of spray.   Please check product labels for rates, post-harvest intervals and safety precautions. Keeping the fields clean of over-ripe and rotten fruit can also help reduce the incidence of this insect.  For information on identifying spotted wing drosophila and making your own monitoring traps, visit the Michigan State University’s Spotted Wing Drosophila website.  There is also a good fact sheet series on management of spotted wing drosophila on the Penn State Extension website.

David T. Handley
Vegetable & Small Fruit Specialist

Highmoor Farm                       Pest Management Office
P.O. Box 179                             491 College Avenue
Monmouth, ME  04259         Orono, ME  04473
207.933.2100                          1.800.287.0279

IPM Web Pages:
http://extension.umaine.edu/ipm/
http://www.pestwatch.psu.edu/sweet_corn.htm
http://www.umass.edu/umext/ipm/

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.

Image Description: Male and Female Spotted Wing Drosophila Flies

Image Description: Fall Raspberries

Image Description: Spotted Wing Drosophila Emerging from Fall Raspberries

Press Herald Interviews Handley, Kirby on Garden Insects

The Portland Press Herald spoke with David Handley, a vegetable and small-fruit specialist with the University of Maine Cooperative Extension in Monmouth, and Clay Kirby, an insect diagnostician with the UMaine Cooperative Extension in Orono, about bugs in the garden. The pair spoke about this season’s likely pests.


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University of Maine Cooperative Extension


Contact Information

Cooperative Extension at Highmoor Farm
52 U.S. Route 202
Monmouth, Maine 04259-0179
Phone: 207.933.2100
The University of Maine
Orono, Maine 04469
207.581.1110
A Member of the University of Maine System