Posts Tagged ‘Maine Integrated Pest Management’

Fruit Growers Alert 7/3/14: First Male SWD in Maine Wild Blueberry Field Caught this Week!

Thursday, July 3rd, 2014

Fruit Growers Alert – July 3, 2014

FIRST MALE SWD IN MAINE WILD BLUEBERRY FIELD CAUGHT THIS WEEK!

We caught our first male spotted wing drosophila (SWD) in a commercial blueberry field in Blue Hill. The traps were put out last week and collected on Monday, June 30, 2014. However, the 15 other fields scouted had no SWD caught. The fruit in the mid-coast wild blueberry fields are just starting to turn blue and thus are susceptible to SWD, and so my recommendation is for all growers to get their traps out as soon as possible.

Frank Drummond
Professor of Insect Ecology/Entomology
University of Maine

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

2013 Spotted Wing Drosophila Summary for Maine Berry Growers

Tuesday, February 25th, 2014

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.

drosophila trap

Drosophila Trap, photo by David Handley

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

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.

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

Monday, September 30th, 2013

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.

Spotted Wing Drosophila Larva in Blackberry

SWD Larvae in Blackberry, photo by David Handley

Spotted Wing Drosophila Maggot in Raspberry

SWD Maggot in Raspberry, photo by David Handley

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.

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

Tuesday, September 3rd, 2013

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.

Fall Raspberries

photo by David Handley

Spotted Wing Drosophila Emerging from Fall Raspberries

photo by James Dill

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.

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

Monday, August 19th, 2013

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 Trap

SWD Trap, photo by David Handley

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.

Male and Female Spotted Wing Drosophila

Male and Female Spotted Wing Drosophila, image by Alan Kenage, Capital Press

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.

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

Monday, July 29th, 2013

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 Trap

SWD Trap, photo by David Handley

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.

Male and Female Spotted Wing Drosophila Flies

Male (left) and Female (right) Spotted Wing Drosophila, photo by Griffin Dill. Actual size: 2-3 mm.

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.

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

Friday, July 19th, 2013

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.

Spotted Wing Drosophila Larvae in Raspberry

Spotted Wing Drosophila Larvae in Raspberry, photo by David Handley

Spotted Wing Drosophila Larvae in Blueberry

Spotted Wing Drosophila Larvae in Blueberry, photo by David Handley

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.

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

Wednesday, July 10th, 2013
Male and Female Spotted Wing Drosophila Flies

Male (left) and Female (right) Spotted Wing Drosophila, photo by Griffin Dill. Actual size: 2-3 mm.

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.

Fall Raspberries

Photo by David Handley

Spotted Wing Drosophila Emerging from Fall Raspberries

Photo by James Dill

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.

Spotted Wing Drosophila 2012 Season Summary for Maine Berry Growers

Monday, December 3rd, 2012

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

David Handley, Vegetable & Small Fruit Specialist; James Dill, Pest Management Specialist; Kaytlin Woodman, Technician, University of Maine Cooperative Extension

In the fall of 2011 we captured spotted wing drosophila flies for the first time in Maine.  Based on crop damage experienced by southern growers in 2010 and 2011, we knew that this insect posed a serious threat to most of the berry crops we grow here.  As part of the University of Maine Cooperative Extension Pest Management Program, we set up drosophila traps in berry fields around the southern, central and coastal regions of the state.  The traps were simply plastic cups with lids mounted on stakes with 16, 1/8” holes punched under the rim to allow the flies access.  Four ounces of bait (a mixture of cider vinegar, white grape juice and alcohol) was poured into each trap.  We placed traps both within the crops and in the wooded areas near the crops, knowing the insect prefers humid, shaded areas.  We emptied the traps weekly and restocked them with fresh bait.  We were hoping the traps would show us when this new pest would start emerging in Maine, and how rapidly populations would build to damaging levels.

The first spotted wing drosophila were caught in Limington on July 13.  By the following week, we had trapped drosophila flies in Springvale, New Gloucester, Poland Spring, Mechanic Falls, Wales, Litchfield, Fayette, Thorndike and Warren.  By August 13, we had captured flies at all of our monitoring locations, adding Buxton, Bowdoinham, Dresden, Turner, Farmington, and Fayette to the list.  During the same week, traps in wild blueberry fields in Hancock and Washington counties were also catching the flies.  In late August trap counts rose dramatically at most locations.  Raspberry and blueberry fruit infested with the small white larvae were being reported, and we received numerous calls about soft, rotting fruit.  Trap counts continued to rise through mid-September, with catches in some locations exceeding 2,000 flies per week. 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.  Populations were highest in the southernmost and coastal regions, but relatively high numbers of flies were caught in nearly all locations at some point in the season.

Growers who were using insecticides to control spotted wing drosophila initially found that weekly sprays appeared to provide adequate control.  However, as fly populations expanded, growers found that twice weekly sprays were needed to keep larvae out of the fruit.  Growers were using Entrust®, Delegate®, Brigade®, Mustang Max®, and/or malathion insecticides, and most found that these products usually offered adequate control if applied on a frequent basis.  Some growers who did not apply pesticides reported total crop loss following the arrival of spotted wing drosophila in their fields.

Spotted Wing Drosophila Trap Captures in Maine, 2012

Spotted Wing Drosophila Trap Captures in Maine, 2012

Spotted Wing Drosophila Trap Captures in Maine 2012 Data (Excel)

Spotted wing drosophila trap catches remained relatively high throughout the remainder of the season, with a slight dip in late September, which may correlate with a dry spell (we are still analyzing weather data).  In fact, some of the highest trap catches occurred late in the season, in early November, well after most of the crops had been harvested or lost to frost.  The lack of food may have made the traps more attractive, accounting for the increased catch, but this still indicates that high numbers of flies appear to 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.

This species over-winters as adults, and research suggests that they should emerge early in the spring to seek out food and begin breeding and laying eggs.  It is thought that the over-wintering survival rate will be relatively low here, but enough should survive to cause similar, if not greater, problems in 2013, given that they will be starting in higher numbers and be more widely dispersed than they were in 2012.

Thus, berry growers should anticipate needing to manage drosophila for the 2013 season.  Based on this year’s data and records from other states, we believe it will be unlikely to significantly infest crops until relatively late in the season when populations reach damaging levels (this year early to mid-August).  Therefore, earlier ripening crops such as June-bearing strawberries should not be significantly impacted, but later ripening crops such as late summer and fall fruiting raspberries, later varieties of blueberries and fall strawberries will need to be protected as soon as fruit begin to ripen.  We plan to again monitor drosophila populations in Maine in 2013, and carry out research on improving our trapping strategies to provide an early warning system in the future.

If you have not yet filled out a grower survey of how spotted wing drosophila impacted your crops this year, click here.  Your input will greatly help us develop our research and educational efforts for the future.  There is a very good fact sheet series on spotted wing drosophila from the Pennsylvania State University, and we have some free copies available.  Contact Pam St. Peter at 207.933.2100 or pamela.stpeter@maine.edu.  You can also download a free copy at their website.

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.


Spotted Wing Drosophila Update for Maine Fruit Growers – August 24, 2012

Spotted Wing Drosophila Trap with One Male SWD Circled

Spotted Wing Drosophila Trap, Male SWD Circled, photo by Kaytlin Woodman

Over the last week and a half, spotted wing drosophila numbers in our traps have increased significantly.  We are now finding both male and female flies in the highest numbers of the season.  In addition, we have found drosophila maggots infesting both highbush blueberry and raspberry fruit this week and have been getting reports from growers around the state of infested fruit.  Some farms have closed berry sales for the season as harvest is coming to an end, and the few fruit remaining will not be worth the extra effort of repeated insecticide sprays to rescue them.  For those with late fruit crops still to harvest, protection will now be necessary to prevent infestation by spotted wing drosophila.  Up to this point weekly applications of an allowed insecticide have been adequate, but reports from the field suggest that more frequent applications will now be necessary to keep fruit free from maggots.  Growers in southern states have found that a three to five-day spray schedule was needed to prevent infestation.

Spotted Wing Drosophila Maggot in Blueberry

Spotted Wing Drosophila Larva in Blueberry, photo by David Handley

Maine Crisis Exemption Label for Gowan Malathion 8 Flowable® to Control Spotted Wing Drosophila on Blueberries:
There are just a few more days left to utilize the  Section 18 Crisis Exemption granted by the EPA for the use of Gowan Malathion 8 Flowable® at a higher rate than the federal label allows, to provide better control of spotted wing drosophila on blueberries.  This label will allow a rate of 2.0 to 2.5 pt/acre per application, with a maximum of two applications per field.  This exemption rate can only be used from August 13 through August 28 this year.  Growers must have a copy of the exemption label in their possession to use this rate, and must fill out a use survey at the end of the season.  Exemption Labels are available through pesticide dealers, and the Board of Pesticides Control (287.7544).

Check product labels for which crops are registered for the product, application limits, 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.

We have available a very good series of new fact sheets from Penn State Extension regarding spotted wing drosophila.  If you would like copies please e-mail Pam St. Peter at pamela.stpeter@maine.edu, or call Pam at 207.933.2100.

David T. Handley
Vegetable & Small Fruit Specialist

Highmoor Farm                      Pest Management Office
P.O. Box179                          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.


Spotted Wing Drosophila Update for Maine Fruit Growers – August 15, 2012

Male Spotted Wing Drosophila

Male Spotted Wing Drosophila, photo by Griffin Dill. Actual size: 2-3 mm.

During the past week we have seen a significant increase in spotted wing drosophila coming to our traps in southern Maine.  This suggests that the threat of infestation to any soft fruit or berries remaining in the field is now very high.  We are catching these fruit flies in all of the locations where we have placed traps including Limington, Buxton, Springvale, Bowdoinham, Dresden, New Gloucester, Poland Spring, Mechanic Falls, Turner, Farmington, Wales, Litchfield, Fayette, Thorndike and Warren.  In addition, traps in wild blueberry fields in Hancock and Washington counties have caught flies during the past week.  We are confident that the fly is now widespread and active through most, if not all, of the southern, mid-state and coastal regions of the state.  Also, as the quantity of fruit available is reduced through harvesting, pressure on the remaining fruit will intensify.  We recommend protecting any berry crops or other soft fruit with an appropriate insecticide on a frequent and regular schedule.  With fly catches increasing, more frequent spray applications will probably be needed to achieve adequate control.  The table below lists available materials and the estimated days of residual activity, assuming the product is not washed off by heavy rains.

Characteristics of Insecticides for Spotted Wing Drosophila Control

Trade Name Days to Harvest
Blueberry
Days of Residual
Malathion 1 5-7
Mustang Max® 1 7
Brigade® 1 7
Delegate® 3 (1 raspberry) 7
Entrust® 3 (0 raspberry) 3-5
PyGanic® 12 hr 2-3

Please check product labels for which crops are registered for the product, application limits, 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.

Maine Crisis Exemption Label for Gowan Malathion 8 Flowable® to Control Spotted Wing Drosophila on Blueberries:
Maine has been granted a Section 18 Crisis Exemption by the EPA for the use of Gowan Malathion 8 Flowable® at a higher rate than the federal label allows, to provide better control of spotted wing drosophila on blueberries.  This label will allow a rate of 2.0 to 2.5 pt/acre per application, with a maximum of two applications per field.  The length of this exemption is very short; this rate can only be used from August 13 through August 28 this year.  Growers must have a copy of the exemption label in their possession to use this rate, and must fill out a use survey at the end of the season.  Exemption Labels are available through pesticide dealers, and the Board of Pesticides Control (287.7544).

We have available a very good series of new fact sheets from Penn State Extension regarding spotted wing drosophila.  If you would like copies please e-mail Pam St. Peter at pamela.stpeter@maine.edu, or call Pam at 207.933.2100.

David T. Handley
Vegetable & Small Fruit Specialist

Highmoor Farm                      Pest Management Office
P.O. Box179                          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.


Spotted Wing Drosophila Update for Maine Fruit Growers – August 1, 2012

Since our first occurrence of spotted wing drosophila in Limington on July 13, we have now found spotted wing drosophila flies in traps in locations in Springvale, New Gloucester, Poland Spring, Mechanic Falls, Wales, Litchfield, Fayette, Thorndike and Warren.  In the past week additional captures have occurred in Buxton, Bucksport and Franklin, in addition to more captures in the earlier locations.  At this point we assume that the fly is fairly widespread and active through most, if not all, of the southern, mid-state and coastal regions of the state.  We recommend protecting any berry crops or other soft fruit with an appropriate insecticide on a frequent and regular schedule.  At the moment weekly applications appear to be keeping drosophila in check.  However, fly catches in most locations are increasing, so the problem is likely to get worse as the season progresses.  Therefore, more frequent spray schedules will probably be needed to achieve adequate control.

Male and Female Spotted Wing Drosophila Flies

Products that provide good control of Drosophila on berries include spinosad products such as Entrust® and Delegate® (group 5), and pyrethroids such as Brigade®, Mustang Max® and Danitol® (group 3).  Please check product labels for which crops are registered for the product, application limits, rates, post-harvest intervals and safety precautions.  Keeping the fields clean of overripe and rotten fruit can also help reduce the incidence of this insect.

We have recently received a very good series of new fact sheets from Penn State Extension regarding identification, biology, monitoring and management of spotted wing drosophila.  Thanks to a grant from the Northeast IPM Center, we can offer you copies of these fact sheets for free until our supply runs out.  If you would like copies please email Pam St. Peter at pamela.stpeter@maine.edu, or call Pam at 207.933.2100.

David T. Handley
Vegetable & Small Fruit Specialist

Highmoor Farm                      Pest Management Office
P.O. Box179                          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.

Spotted Wing Drosophila Management

Trade Name Active Ingredient Preharvest Interval (days)a Effectiveness Length of Residual Activity
Raspberries Blackberries Strawberries Cherries
Pyrethroids and Pyrethrins (IRAC Activity Group 3A)
Brigade bifenthrin 3 3 0 X Excellent 7 days
Danitol fenpropathrin 3b 3b 2b 3b Excellent 7 days
Baythroid beta-cyfluthrin X X X 7b Excellent 7 days
Mustang Max zeta-cypermethrin 1b 1b X 14b Excellent 7 days
PyGanicc pyrethrins 0 0 0 0 Goodd 0-2 days
Spinosyns (IRAC Activity Group 5)
Delegate spinetoram 1b 1b X 7b Excellent 5-7 days
Radiant spinetoram X X 1 X Excellent 5-7 days
Spintor spinosad 1 1 1 7 Excellent 5-7 days
Success spinosad 1b 1b 1 7b Excellent 5-7 days
Entrustc spinosad 1b 1b 1 7b Excellent 5-7 days
Organophosphates (IRAC Activity Group 1B)
Malathion malathion 1 1 3 3 Excellent >7 days
Diazinon diazinon X X 5 21 Excellent >7 days

a.   “X” = the material is not labeled for use on the crop.
b.   2(ee) labels have been issued for use against SWD on this crop.
c.   May be used in organic production.  For PyGanic, the REI is 12 hours even though the PHI is 0 days.
d.   Provides knockdown of nonresistant populations but has little or no residual activity.
From Penn State Extension “Spotted Wing Drosophila, Part 4: Management.”  http://extension.psu.edu/fruit-times/news/2012/spotted-wing-drosophila-fact-sheets-completed-and-on-line.


 

Spotted Wing Drosophila Update for Maine Fruit Growers – July 23, 2012

Male Spotted Wing Drosophila

Male Spotted Wing Drosophila, photo by Griffin Dill. Actual size: 2-3 mm.

The first spotted wing drosophila of the 2012 season was found in a trap in Limington on Friday, July 13.  Since that time, we have found spotted wing drosophila flies in our traps at locations in Springvale, New Gloucester, Poland Spring, Mechanic Falls, Wales, Litchfield, Fayette, Thorndike and Warren.  While we have not yet caught the flies at all of the locations where we are trapping, it would be best to assume that the fly is now fairly widespread and active through much of the state.  Therefore, if you presently have ripening berry crops or other soft fruit, we are recommending protecting them with an appropriate insecticide on a regular basis at this time.  We are catching relatively low numbers of flies at these locations but the numbers have started to increase.  We know that the traps only tell us when the fly is already in the field, and we also know how rapidly the population can explode, so we are recommending preventive measures be taken as soon as possible.

Male and Female Spotted Wing Drosophila Flies

Products that provide good control of drosophila on berries include spinosad products such as Entrust®, Radiant® and Delegate® (group 5), and pyrethroids such as Brigade®, Mustang Max® and Danitol® (group 3).  Please check product labels for which crops are registered for the product, 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.

Male and Female Spotted Wing Drosophila

Male and Female Spotted Wing Drosophila, image by Alan Kenage, Capital Press

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 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 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.


Fruit Growers Alert: Spotted Wing Drosophila has been found in Maine!  July 13, 2012

The first spotted wing drosophila of the 2012 season was found in a trap in Limington on Friday, July 13.  Three male flies were caught in a trap in the woods adjacent to a raspberry planting.  We haven’t caught flies in other locations yet, but growers should be on alert for indications of fruit flies in their plantings and premature fruit decay.

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 flies 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 recently came into the U.S. from northern Asia, and caused problems with many berry crops up the east coast last year.  It can complete a generation in under two weeks, with each adult female laying hundreds of eggs.  Therefore, millions of flies can be present soon after the introduction of just a few into a field.  This makes them very difficult to control, and frequently repeated insecticide sprays (3 to 5 times per week) may be needed to prevent infestations once the insect is present in a field.  It is likely that spotted winged drosophila can successfully overwinter here, although it may not build up to damaging levels until summer.  We have set out monitoring traps for spotted winged drosophila in fruit plantings around the state to determine the activity of this pest in Maine.  However, these traps are unlikely to provide early warning, i.e. when we find them in a trap they are probably already established in the field.  We will be alerting growers when we find them in Maine.  Now that spotted wing drosophila has been confirmed in a berry planting in southern 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®, Danitol®, and malathion.  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 on management of spotted wing drosophila on the Penn State Extension website.

David T. Handley, Ph.D.
Vegetable & Small Fruit Specialist

University of Maine Cooperative Extension
Highmoor Farm
P.O. Box179
Monmouth, ME  04259-0179
Tel. 207.933.2100
Fax 207.933.4647
david.handley@maine.edu

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.