Spotted Wing Drosophila Update: August 26, 2016

August 26th, 2016 1:45 PM

SPOTTED WING DROSOPHILA UPDATE: AUGUST 26, 2016

Click on photo to enlarge.

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

Spotted Wing Drosophila

Spotted Wing Drosophila, photo by James Dill

Spotted wing drosophila populations are rising around the state, but numbers have only increased dramatically in sites that have not been sprayed. This indicates that control measures at other sites have been effective at suppressing infestations. We have been able to find larvae in waste fruit at several of our monitoring sites. We expect pressure to increase significantly once we start getting more rain and temperatures begin to cool. Spotted wing drosophila numbers are over levels that call for management in all of our trapping sites, except Wales. You should assume that spotted wing drosophila will infest any ripe fruit in southern and central Maine that is not protected by regular insecticide sprays. Frequent scouting for spotted wing drosophila flies and larvae should be carried out in berry fields with ripening fruit. At this time, a seven-day spray schedule of an appropriate insecticide has been providing adequate control of the flies. (See the New England Small Fruit Management Guide for more information and details.) When populations increase, a more frequent spray schedule will be necessary to prevent infestations.

Town Spotted Wing Drosophila weekly trap catch 8/15/16 Spotted Wing Drosophila weekly trap catch 8/25/16
Limington* 405 972
Limerick 8 13
Springvale 17 48
Wells 31 41
Cape Elizabeth 23 71
Bowdoinham 41 43
Dresden 37 41
Freeport 2 13
Poland Spring 7 8
Mechanic Falls 3 17
Monmouth* 6 355
Fayette 19 20
Wales 3 1
*unsprayed planting

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

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

IPM Web Pages:
Michigan State University
Penn State University
University of New Hampshire

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.

 

 

Sweet Corn IPM Newsletter No. 10 – August 26, 2017

August 26th, 2016 11:34 AM

Sweet CornSweet Corn IPM Newsletter No. 10 – August 26, 2016
Click on photos to enlarge.

CORN EARWORM THREATENS LATE SILKING CORN

Fall Armyworm also Attacking Late Corn

SITUATION
A little bit of much-needed rain last weekend offered some relief to the dry conditions, but also brought an increase in corn earworm activity in most fields. Fall armyworm counts continue to be high at most sites, and birds and mammals have been causing lots of damage to ripening fields. Growers are still spending much of their time managing irrigation, and as a result the supply and quality of corn has been very good.

European corn borer: Moth counts have been rising in some locations this week, suggesting a second generation of European corn borer may be getting underway. However, in most cases fields are now under a spray schedule for corn earworm, and therefore no additional sprays should be required. Fields in Poland Spring, Sabattus, Wales, Warren and one Wells site exceeded the 5-moth control threshold for silking corn. Only the field in Sabattus was not already under a spray interval for corn earworm, so a spray for silking corn was recommended.

Corn earworm: Moth counts are generally higher around the state this week. Most farms are now on a spray schedule for corn earworm on all silking corn. A 6-day spray interval for all silking corn was recommended in Bowdoinham, one Cape Elizabeth site, Dayton, Levant, North Berwick, Oxford, and Wales. A five-day spray interval was recommended in Biddeford, Monmouth, Poland Spring, Wayne, and one Wells site. A 4-day spray interval was recommended at one Cape Elizabeth site, Hollis, Lewiston New Gloucester, Nobleboro, Warren, and one Wells site.

Fall armyworm: Moth counts continue to be over the spray threshold for silking corn in most locations, but most of these fields are now under a regular spray schedule for corn earworm, so no additional sprays should be needed for fall armyworm. Moth catches were over the 3-moth spray threshold in Biddeford, Bowdoinham, Cape Elizabeth, Dayton, Hollis, Durham, Levant, Lewiston, Monmouth, New Gloucester, Nobleboro, North Berwick, Oxford, Poland Spring, Sabattus, Wales, Warren, Wayne and one Wells site. Most of the remaining corn is in silk, so spray recommendations are being based on trap catches rather than field scouting for plant damage. Fall armyworm pressure will likely remain high for the rest of the season.

Fall Armyworm on Corn Silk

Fall Armyworm on Corn Silk, photo by David Handley

SWD Maggot in Raspberry

SWD Maggot in Raspberry, photo by David Handley

Spotted wing drosophila: Fly numbers continue to rise, but have only increased dramatically in plantings that have not been sprayed, indicating that sprays have been effective at keeping infestations at manageable levels in most fields. Berry growers should continue spraying ripening fruit regularly to prevent infestations. A 7-day spray schedule appears to be providing adequate protection at this time. For more information visit our Spotted Wing Drosophila blog.

Hops Plant

Hops Plant, photo by David Handley

Hops Twilight Meeting: Are you interested in growing hops? There has been lots of talk about the potential for this crop in Maine. Come join us at the Hop Yard, 26 Hamblen Drive, Gorham, Maine on Wednesday, September 14 from 5:00 p.m. to 7:30 p.m. Grower Ryan Houghton will tour us through the planting and discuss his experience in starting a commercial hops planting. David Handley and Jim Dill from the University of Maine Cooperative Extension will also be on hand to discuss growing practices and pest problems. Hold the date! More details are coming soon.

Sincerely,

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

Sweet Corn IPM Weekly Scouting Summary

Location CEW
Moths
ECB
Moths
FAW
Moths
Recommendations / Comments
Biddeford 4 0 42 5-day spray interval on silking corn for CEW
Bowdoinham 2 0 15 6-day spray interval on silking corn for CEW
Cape Elizabeth I 12 0 50 4-day spray interval on silking corn for CEW
Cape Elizabeth II 3 2 65 6-day spray interval on silking corn for CEW
Charleston 0 0 0 No spray recommended
Corinth 0 1 0 No spray recommended
Dayton 3 0 3 6-day spray interval on silking corn for CEW
Hollis 13 1 35 4-day spray interval on silking corn for CEW
Durham 0* 0 4 One spray for FAW on silking corn (*CEW trap down)
Levant 2 0 7 6-day spray interval on silking corn for CEW
Lewiston 13 2 33 4-day spray interval on silking corn for CEW
Monmouth 6 1 35 5-day spray interval on silking corn for CEW
New Gloucester 9 2 100 4-day spray interval on silking corn for CEW
Nobleboro 12 2 24 4-day spray interval on silking corn for CEW
No. Berwick 3 2 32 6-day spray interval on silking corn for CEW
Oxford 3 2 59 6-day spray interval on silking corn for CEW
Palmyra 0 1 0 No spray recommended
Poland Spring 5 12 9 5-day spray interval on silking corn for CEW
Sabattus 0 19 3 One spray for ECB on silking corn
Wales 2 6 3 6-day spray interval on silking corn for CEW
Warren 12 23 51 4-day spray interval on silking corn for CEW
Wayne 7 1 30 5-day spray interval on silking corn for CEW
Wells I 6 2 2 5-day spray interval on silking corn for CEW
Wells II 11 5 156 4-day spray interval on silking corn for CEW

CEW: Corn earworm (Only fresh silking corn should be sprayed for this insect.)
ECB: European corn borer
FAW: Fall armyworm

Corn Earworm Spray Thresholds for Pheromone Traps

Moths caught per week Moths caught per night Spray interval
0.0 to 1.4 0.0 to 0.2 No spray
1.5 to 3.5 0.3 to 0.5 Spray every 6 days
3.6 to 7.0 0.6 to 1.0 Spray every 5 days
7.1 to 91 1.1 to 13.0 Spray every 4 days
More than 91 More than 13 Spray every 3 days

Thresholds apply only to corn with exposed fresh silk. Lengthen spray intervals by one day if maximum daily temperature is less than 80°F.

European Corn Borer Thresholds
Whorl stage: 30% or more of plants scouted show injury.
Pre-tassel-silk: 15% or more of plants scouted show injury.
Silk: 5 or more moths caught in pheromone traps in one week.

IPM Web Pages:
UMaine Cooperative Extension IPM
Penn State Sweet Corn IPM
UMass Extension IPM Programs

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.

Spotted Wing Drosophila Update: August 19, 2016

August 19th, 2016 1:46 PM

SPOTTED WING DROSOPHILA UPDATE: AUGUST 19, 2016

Click on photo to enlarge.

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

Spotted Wing Drosophila Larva in Blackberry

SWD Larvae in Blackberry, photo by David Handley

Spotted wing drosophila populations continue to slowly increase in numbers and distribution around the state. The persistent hot, dry weather also continues and is probably preventing a more rapid rise in drosophila activity, despite food becoming more available. Fly numbers are now over levels that call for immediate action in all of our trapping sites, except Freeport, Mechanic Falls and Wales. However, it is safest to assume that spotted wing drosophila is likely to infest any ripe fruit in southern and central Maine that is not protected by regular insecticide sprays. Frequent scouting for spotted wing drosophila flies and larvae should continue in berry fields with ripening fruit. A seven-day spray schedule of an appropriate insecticide should provide adequate control of the flies once adults or larvae are found in the planting at this point. (See the New England Small Fruit Management Guide for more information and details.) Should temperatures and rain start to fall, we expect populations will rapidly increase and a more frequent spray schedule will be necessary to prevent infestations.

Town Spotted Wing Drosophila weekly trap catch 8/8/16 Spotted Wing Drosophila weekly trap catch 8/15/16
Limington 125 405
Limerick 18 8
Springvale 2 17
Wells 1 31
Cape Elizabeth 28 23
Bowdoinham 42 41
Dresden 26 37
Freeport 1 2
Buxton 22 18
Poland Spring 4 7
Mechanic Falls 2 3
Monmouth 9 6
Fayette 30 19
Wales 0 3

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

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

IPM Web Pages:
Michigan State University
Pennsylvania State University
University of New Hampshire

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.

 

 

Sweet Corn IPM Newsletter No. 9 – August 19, 2016

August 19th, 2016 12:36 PM

Sweet CornSweet Corn IPM Newsletter No. 9 – August 19, 2016
Click on photos to enlarge.

CORN EARWORM NUMBERS INCREASING

Fall Armyworm Damaging Pre-Tassel Corn

SITUATION
While dry conditions continue to dominate grower concerns, harvested cornfields are now being plowed down to make ready for cover crops. Mid and late season corn harvest is underway. The high temperatures have hastened ripening of many fields, condensing the harvest window and making the supply less consistent than usual. Insect pressure is higher in some, but not all, locations this week. Fall armyworm feeding in younger corn is still a concern in late maturing fields.

European corn borer: We are still finding low numbers of moths in most locations, but some sites have seen an increase in trap catches this week. Fields in Levant, North Berwick, Palmyra, Sabattus, Warren and one Wells site exceeded the 5-moth control threshold for silking corn. The fields in North Berwick, Palmyra and Sabattus were not already under a spray interval for corn earworm, so a spray was recommended. Larval feeding damage was very light, with no fields exceeding the 15% pre-tassel threshold.

Corn earworm: Moth counts were inconsistent around the state, with some fields showing a significant increase in numbers from last week, and many fields still catching very few or no moths. A 6-day spray interval for all silking corn was recommended in Bowdoinham, Levant, Livermore Falls, New Gloucester, Nobleboro and Oxford. A five-day spray interval was recommended in Biddeford, one Cape Elizabeth site and one Wells site. A 4-day spray interval was recommended at one Lewiston site, and Warren.

Corn Earworm Moth

Corn Earworm Moth, photo by David Handley

Fall Armyworm on Corn Silk

Fall Armyworm on Corn Silk, photo by David Handley

Fall armyworm: Moth counts were high in more locations this week, although a few sites still have not exceeded the threshold for silking corn. Moth counts did exceed the 3-moth spray threshold in Biddeford, Cape Elizabeth, Farmington, Levant, Lewiston, Monmouth, New Gloucester, Nobleboro, Oxford, Wales, Warren and one Wells site. Larval feeding damage exceeded the 15% feeding injury threshold on pre-tassel corn in Cape Elizabeth, Hollis, one Lewiston site, Livermore Falls, New Gloucester, Oxford and one Wells site. Some locations now have all of their remaining corn in silk, so sprays are based primarily on trap catches rather than field scouting for plant damage. High moth catches suggest armyworm pressure will remain high in the coming weeks.

Spotted wing drosophila: Fly numbers are climbing around the state, but haven’t yet exploded. However, nearly all of our trapping sites are now over the recommended threshold for protecting ripening fruit. Berry growers should be spraying ripening fruit regularly to prevent infestations. At this point, a 7-day spray schedule should provide adequate protection. For more information visit our Spotted Wing Drosophila blog.

Spotted Wing Drosophila Larvae in Raspberry

Spotted Wing Drosophila Larvae in Raspberry, photo by David Handley

Bird Damage on Corn

Bird Damage on Corn, photo by David Handley

Birds, etc.: Flocking species of blackbirds have been damaging cornfields around the state. Birds tend to be more of a problem in dry years, when food and water is more difficult to find. They are especially attracted to fields where corn has been allowed to get over-mature. Deer and raccoons have also been very troublesome this year. For information on wildlife problems and management options, you may call the Animal and Plant Health Inspection Service (APHIS) office in Augusta at 1.866.487.3297.

Sincerely,

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

Sweet Corn IPM Weekly Scouting Summary

Location CEW
Moths
ECB
Moths
FAW
Moths
%Feeding
Damage
Recommendations / Comments
Biddeford 6 0 42 5-day spray interval on silking corn for CEW
Bowdoinham 2 3 1 2% 6-day spray interval on silking corn for CEW
Cape Elizabeth I 7 0 30 79% 5-day spray interval on silking corn for CEW
Cape Elizabeth II 1 2 37 41% One spray for FAW on all corn
Charleston 0 1 1 0% No spray recommended
Corinth 0 2 1 2% No spray recommended
Dayton 1 0 1 11% No spray recommended
Hollis 1 1 0 57% One spray for FAW on pre-tassel corn
Farmington 0 0 4 One spray for FAW on silking corn
Levant 3 5 3 3% 6-day spray interval on silking corn for CEW
Lewiston I 11 2 2 4-day spray interval on silking corn for CEW
Lewiston II 0 0 62 19% One spray for FAW on all corn
Livermore Falls 3 1 1 25% 6-day spray interval on silking corn for CEW
Monmouth 1 0 17 One spray for FAW on silking corn
New Gloucester 2 1 14 18% 6-day spray interval on silking corn for CEW
Nobleboro 3 0 29 0% 6-day spray interval on silking corn for CEW
No. Berwick 1 5 0 7% One spray for ECB on silking corn
Oxford 2 0 15 19% 6-day spray interval on silking corn for CEW
Palmyra 1 6 0 0% One spray for ECB on silking corn
Poland Spring 0 3 0 7% No spray recommended
Sabattus 0 20 1 One spray for ECB on silking corn
Wales 1 2 4 One spray for FAW on silking corn
Warren 9 19 49 4-day spray interval on silking corn for CEW
Wells I 0 1 1 0% No spray recommended
Wells II 5 6 70 26% 5-day spray interval on silking corn for CEW

CEW: Corn earworm (Only fresh silking corn should be sprayed for this insect.)
ECB: European corn borer
FAW: Fall armyworm

Corn Earworm Spray Thresholds for Pheromone Traps

Moths caught per week Moths caught per night Spray interval
0.0 to 1.4 0.0 to 0.2 No spray
1.5 to 3.5 0.3 to 0.5 Spray every 6 days
3.6 to 7.0 0.6 to 1.0 Spray every 5 days
7.1 to 91 1.1 to 13.0 Spray every 4 days
More than 91 More than 13 Spray every 3 days

Thresholds apply only to corn with exposed fresh silk. Lengthen spray intervals by one day if maximum daily temperature is less than 80°F.

European Corn Borer Thresholds
Whorl stage: 30% or more of plants scouted show injury.
Pre-tassel-silk: 15% or more of plants scouted show injury.
Silk: 5 or more moths caught in pheromone traps in one week.

IPM Web Pages:
UMaine Cooperative Extension IPM
Penn State Sweet Corn IPM
UMass Extension IPM Programs

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.

Spotted Wing Drosophila Update: August 12, 2016

August 12th, 2016 11:57 AM

SPOTTED WING DROSOPHILA UPDATE: AUGUST 12, 2016

Click on photo to enlarge.

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

Spotted Wing Drosophila Larvae in Blueberry

Spotted Wing Drosophila Larvae in Blueberry, photo by David Handley

Spotted wing drosophila populations generally increased in numbers and distribution this week. Although hot, dry weather may be slowing drosophila activity for the moment, we anticipate numbers will rise when cooler, more humid conditions arrive. Fly numbers are now over levels that call for immediate action in Limington, Limerick, Cape Elizabeth, Dresden, Fayette, Bowdoinham, Buxton, Monmouth and Fayette. We have also been finding larvae in unsprayed raspberry fruit. At this point, it would be safest to assume that spotted wing drosophila is now likely to infest any ripe fruit in southern and central Maine that is not protected by regular insecticide sprays. Frequent scouting for spotted wing drosophila flies and larvae should be carried out in berry fields with ripening fruit. A seven-day spray schedule of an appropriate insecticide should provide adequate control of the flies once adults or larvae are found in the planting. (See the New England Small Fruit Management Guide for more information and details.) Once temperatures cool down and rain moves into the state, populations will increase quickly and more frequent sprays may be necessary to prevent infestations.

Town Spotted Wing Drosophila weekly trap catch 8/1/16 Spotted Wing Drosophila weekly trap catch 8/8/16
Limington 83 125
Limerick 0 18
Springvale 3 2
Wells 1 1
Cape Elizabeth 0 28
Bowdoinham 24 42
Dresden 8 26
Freeport 1 1
Buxton 1 22
Poland Spring 1 4
Mechanic Falls 0 2
Monmouth 0 9
Fayette 6 30
Wales 0 0

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

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

IPM Web Pages:
Michigan State University
Pennsylvania State University
University of New Hampshire

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.

 

 

Sweet Corn IPM Newsletter No. 8 – August 12, 2016

August 12th, 2016 10:35 AM

Sweet CornSweet Corn IPM Newsletter No. 8 – August 12, 2016

Click on photos to enlarge.

CORN PEST PRESSURE MODERATE

Fall Armyworm Numbers High in Some Sites, but Other Pest Counts are Low

SITUATION
The lack of rain continues to be the most pressing issue for vegetable growers in much of the state, as irrigation management occupies much of our time. Harvest is in full swing, and overall quality is good, although some have felt the impact of the drought with smaller ear size and poor tip fill. Insect and disease pressure remains light for this time of the season, as earworm and European corn borer populations remain very low, and fall armyworm continues to be the primary problem in most fields.

European corn borer: We are finding low numbers of moths in most locations, although it is still too early to tell if this is the start of a second generation of European corn borer. Fields in Levant, North Berwick and Palmyra exceeded the 5-moth control threshold for silking corn, but only the field in Palmyra was not already under a spray interval for corn earworm. Larval feeding damage was very light, with no fields exceeding the 15% pre-tassel threshold.

Corn earworm: Moth counts were low overall around the state, with some fields showing a decline in counts from last week, and many fields catching no moths. A 6-day spray interval for all silking corn was recommended in Biddeford, Levant, one Lewiston site, North Berwick, and one Wells site. Tropical storm season is starting to brew in the Atlantic, and should storms move up the east coast into New England, we can expect corn earworm and fall armyworm numbers to increase dramatically.

Corn Earworm Larvae

Corn Earworm Larvae, photo by David Handley

Fall Armyworm on Corn Leaf

Fall Armyworm on Corn Leaf, photo by David Handley

Fall armyworm: Moth counts continue to be spotty around the state, with some sites having few or no moths, and others having very high numbers. Fall armyworm is still a threat for many farms. Moth counts exceeded the 3-moth spray threshold for silking corn in Biddeford, Cape Elizabeth, Hollis, Lewiston, Livermore Falls, New Gloucester, Oxford, Poland Spring, and one Wells site. Fields being sprayed for corn earworm should not require additional sprays for fall armyworm. Larval feeding damage exceeded the 15% feeding injury threshold on pre-tassel corn in Cape Elizabeth, one Lewiston site and Warren.

Corn leaf aphids: Remember that aphids can become a cosmetic issue on silks and husks of corn, especially when regular sprays for earworm are not controlling them. If you have not had to spray for the major pests, check to be sure that aphids are not starting to build up on the ears.

Spotted wing drosophila: Fly numbers in traps continue to climb around the state, although slowly. We haven’t yet seen a big increase in populations, but nearly all of our trapping sites are now over the recommended threshold for protecting ripening fruit. We have also been finding more larvae in unsprayed berries. Berry growers should begin spraying ripening fruit to prevent infestations. For more information visit our Spotted Wing Drosophila blog.

Spotted Wing Drosophila Larva in Blackberry

SWD Larvae in Blackberry, photo by David Handley

Squash Vine Borer Larva

Squash Vine Borer Larva, photo by David Handley

Squash vine borer: Trap counts continue to decrease in most locations, but were still high enough in some southern and coastal locations to warrant concern. We have seen some infestations in pumpkin and winter squash this week. Wilting caused by the borers can be mistaken for drought stress. Look for tunneling holes and waste on stems near the base of the plants to determine if borers are present.

Sincerely,

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

Sweet Corn IPM Weekly Scouting Summary

Location CEW
Moths
ECB
Moths
FAW
Moths
%Feeding
Damage
Recommendations / Comments
Biddeford 2 0 14 8% 6-day spray interval on silking corn for CEW
Bowdoinham 0 3 0 7% No spray recommended
Cape Elizabeth I 1 0 29 15% One spray for FAW on silking corn
Cape Elizabeth II 1 1 4 58% One spray for FAW on all corn
Charleston 0 0 0 0% No spray recommended
Dayton 0 0 1 16% One spray for FAW on pre-tassel corn
Hollis 0 1 3 0% One spray for FAW on silking corn
Farmington 0 0 1 No spray recommended
Garland 0 2 2 No spray recommended
Levant 3 5 0 3% 6-day spray interval on silking corn for CEW
Lewiston I 2 2 23 1% 6-day spray interval on silking corn for CEW
Lewiston II 0 0 52 17% One spray for FAW on all corn
Livermore Falls 1 0 13 0% One spray for FAW on silking corn
Monmouth 0 0 2 2% No spray recommended
New Gloucester 1 0 12 10% One spray for FAW on silking corn
Nobleboro 1 0 1 No spray recommended
No. Berwick 2 6 0 9% 6-day spray interval on silking corn for CEW
Oxford 0 2 5 0% One spray for FAW on silking corn
Palmyra 0 5 0 0% One spray for ECB on silking corn
Poland Spring 0 1 3 4% One spray for FAW on silking corn
Sabattus 0 0 0 No spray recommended
Wales 0 0 1 1% No spray recommended
Warren 0 1 2 55% One spray for FAW on pre-tassel corn
Wells I 1 2 1 6% No spray recommended
Wells II 3 0 42 8% 6-day spray interval on silking corn for CEW

CEW: Corn earworm (Only fresh silking corn should be sprayed for this insect.)
ECB: European corn borer
FAW: Fall armyworm

Corn Earworm Spray Thresholds for Pheromone Traps

Moths caught per week Moths caught per night Spray interval
0.0 to 1.4 0.0 to 0.2 No spray
1.5 to 3.5 0.3 to 0.5 Spray every 6 days
3.6 to 7.0 0.6 to 1.0 Spray every 5 days
7.1 to 91 1.1 to 13.0 Spray every 4 days
More than 91 More than 13 Spray every 3 days

Thresholds apply only to corn with exposed fresh silk. Lengthen spray intervals by one day if maximum daily temperature is less than 80°F.

European Corn Borer Thresholds
Whorl stage: 30% or more of plants scouted show injury.
Pre-tassel-silk: 15% or more of plants scouted show injury.
Silk: 5 or more moths caught in pheromone traps in one week.

IPM Web Pages:
UMaine Cooperative Extension IPM
Penn State Sweet Corn IPM
UMass Extension IPM Programs

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.

Spotted Wing Drosophila Update: August 10, 2016

August 10th, 2016 1:29 PM

SPOTTED WING DROSOPHILA UPDATE: AUGUST 10, 2016

Click on photos to enlarge.

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

Spotted Wing Drosophila Larvae in Raspberry

Spotted Wing Drosophila Larvae in Raspberry, photo by David Handley

Spotted wing drosophila populations continue to increase in numbers and distribution this week at most trapping sites. Hot, dry weather appears to be slowing drosophila activity for the moment but we expect numbers to rise when the cooler, more humid conditions they prefer become prevalent. Fly numbers are now over levels that call for immediate action in Limington, Limerick, Dresden, Fayette, Bowdoinham, and Buxton. Some inland sites, especially further north, are still catching few, if any flies, and berries there may not yet require protection. Scouting for spotted wing drosophila flies and larvae should continue frequently in berry fields with ripening fruit. A seven-day spray schedule of an appropriate insecticide should provide adequate control of the flies once adults or larvae are found in the planting. (See the New England Small Fruit Management Guide for more information and details.) Once temperatures cool down and rain moves into the state, populations will increase quickly and more frequent sprays may be necessary to prevent infestations.

Town Spotted Wing Drosophila weekly trap catch 7/29/16 Spotted Wing Drosophila weekly trap catch 8/4/16
Limington 83 125
Limerick 0 18
Springvale 3 2
Wells 1 1
Cape Elizabeth 0 0
Bowdoinham 17 24
Dresden 2 8
Freeport 3 1
Buxton 1 22
Mechanic Falls 0 2
Monmouth 0 0
Fayette 3 6
Wales 0 0

 

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

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

IPM Web Pages:
Michigan State University
Pennsylvania State University
University of New Hampshire

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.

Sweet Corn IPM Newsletter No. 7 – August 5, 2016

August 5th, 2016 11:18 AM

Sweet CornSweet Corn IPM Newsletter No. 7 – August 5, 2016
Click on photos to enlarge.

CORN EARWORM NUMBERS RISING

Fall Armyworm Numbers Remain High, European Corn Borer Counts Increasing

SITUATION
Most growers are struggling to keep enough water on their cornfields to keep the drought from affecting crop yield and quality. Harvest is well underway in southern Maine and quality has been good. The pest situation remains moderate, although corn earworm pressure is slowly building in parts of southern and coastal Maine. Fall armyworm continues to be the most prevalent problem, and some sites are seeing an increase in European corn borer moths.

European corn borer: Moth counts were slightly higher and more widely distributed this week suggesting that a second generation of European corn borer may be getting started. However, only one field in Sabattus exceeded the 5-moth control threshold for silking corn. Larval feeding damage was very light, with no fields exceeding the 15% pre-tassel threshold.

Corn earworm: Although moth counts rose in many locations this week, about half of our sites caught no moths. A 6-day spray interval for all silking corn was recommended in Bowdoinham, Cape Elizabeth, Charleston, Dayton and one Lewiston site. A 5-day spray interval was recommended for silking corn in Biddeford and one Cape Elizabeth site. Corn not yet in silk does not need to be protected from corn earworm. Once the silks on the ears have dried, corn earworm moths are unlikely to lay eggs on it, so sprays can be stopped at that time.

Corn Earworm Feeding on Corn

Corn Earworm Feeding on Corn, photo by David Handley

Fall Armyworm Injury on Corn Leaves

Fall Armyworm Injury on Corn Leaves, photo by David Handley

Fall armyworm: Moths continue to be caught at most sites and in very high numbers in some locations. Fall armyworm is still the major threat to silking corn for many farms, although more sites are now spraying silking corn for corn earworm. Sprays for fall armyworm on silking corn were recommended in Lewiston, Livermore Falls, Monmouth, New Gloucester, Nobleboro, North Berwick, Oxford, Poland Spring, Sabattus and Wells. Fields being sprayed for corn earworm should not require additional sprays for fall armyworm. Feeding damage exceeded the 15% feeding injury threshold in Biddeford and Cape Elizabeth. Fall armyworm larvae can be difficult to control. It is important to apply sprays when the larvae are small, and have not yet burrowed into the protection of the whorls or ear channels where it is difficult to reach them. Make sure the sprayer is providing good coverage of the leaves and that the material is getting into the whorls and emerging tassels. Consider mixing a spreader into the spray to improve distribution across the surface of the leaves.

Spotted wing drosophila: Numbers in traps are starting to creep upwards, but we haven’t yet seen a big increase in flies at most locations. Sites in Limington and Bowdoinham have caught flies above the threshold level, and sprays are recommended for any ripening fruit. We have been finding larvae in some unsprayed raspberries, so growers should be on alert for symptoms and be ready to protect fruit when any flies or larvae are found. For more information visit our Spotted Wing Drosophila blog.

Male Spotted Wing Drosophila

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

Squash Vine Borer Larva

Squash Vine Borer Larva, photo by Jeffrey Hahn, Univ. of Minnesota Extension

Squash vine borer: Moth counts have decreased significantly over the past week. Only one site in New Gloucester was over the 5-moth threshold. There is usually only one generation of this insect each year, so the threat to late-planted squash should be reduced. Stay alert for squash vine borer symptoms and protect plants if damage is seen.

Sincerely,

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

Sweet Corn IPM Weekly Scouting Summary

Location CEW
Moths
ECB
Moths
FAW
Moths
%Feeding
Damage
Recommendations / Comments
Biddeford 4 1 9 30% 5-day spray interval on silking corn for CEW
Bowdoinham 2 1 1 8% 6-day spray interval on silking corn for CEW
Cape Elizabeth I 3 0 39 20% 6-day spray interval on silking corn for CEW
Cape Elizabeth II 4 0 61 5-day spray interval on silking corn for CEW
Charleston 2 0 0 0% 6-day spray interval on silking corn for CEW
Dayton 3 0 3 0% 6-day spray interval on silking corn for CEW
Hollis 0 0 24 0% One spray for FAW on silking corn
Farmington 0 2 1 No spray recommended
Garland 0 0 1 3% No spray recommended
Levant 0 0 2 2% No spray recommended
Lewiston I 2 1 12 0% 6-day spray interval on silking corn for CEW
Lewiston II 1 1 11 13% One spray for FAW on silking corn
Livermore Falls 0 1 5 2% One spray for FAW on silking corn
Monmouth 0 0 8 8% One spray for FAW on silking corn
New Gloucester 0 0 11 2% One spray for FAW on silking corn
Nobleboro 0 0 4 One spray for FAW on silking corn
No. Berwick 1 4 14 0% One spray for FAW on silking corn
Oxford 0 2 4 0% One spray for FAW on silking corn
Palmyra 0 4 0 1% No spray recommended
Poland Spring 0 2 5 8% One spray for FAW on silking corn
Sabattus 1 5 1 0% One spray for ECB on silking corn
Wales 0 0 1 7% No spray recommended
Warren 0 3 0 No spray recommended
Wells I 1 0 32 10% One spray for FAW on silking corn
Wells II 0 0 40 4% One spray for FAW on silking corn

CEW: Corn earworm (Only fresh silking corn should be sprayed for this insect.)
ECB: European corn borer
FAW: Fall armyworm

Corn Earworm Spray Thresholds for Pheromone Traps

Moths caught per week Moths caught per night Spray interval
0.0 to 1.4 0.0 to 0.2 No spray
1.5 to 3.5 0.3 to 0.5 Spray every 6 days
3.6 to 7.0 0.6 to 1.0 Spray every 5 days
7.1 to 91 1.1 to 13.0 Spray every 4 days
More than 91 More than 13 Spray every 3 days

Thresholds apply only to corn with exposed fresh silk. Lengthen spray intervals by one day if maximum daily temperature is less than 80°F.

European Corn Borer Thresholds
Whorl stage: 30% or more of plants scouted show injury.
Pre-tassel-silk: 15% or more of plants scouted show injury.
Silk: 5 or more moths caught in pheromone traps in one week.

IPM Web Pages:
UMaine Cooperative Extension IPM
Penn State Sweet Corn IPM
UMass Extension IPM Programs

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.

Spotted Wing Drosophila Update: August 3, 2016

August 3rd, 2016 11:51 AM

SPOTTED WING DROSOPHILA UPDATE: AUGUST 3, 2016

Click on photos to enlarge.

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

Male and Female Spotted Wing Drosophila

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

There has been an increase in spotted wing drosophila populations at most trapping sites this week, especially in southern and coastal sites. Hot, dry weather tends to reduce drosophila activity, as they prefer cooler, more humid conditions, and this has likely kept populations from climbing more rapidly this season, despite the increasing availability of food, with raspberries, blueberries and blackberries now coming into full harvest. However, fly numbers remained below levels that call for immediate action except for sites in Limington and Bowdoinham. We also found larvae feeding in unsprayed fruit at the Limington site. Research in Maine and other regions suggests that when 6 to 10 flies are caught in a yeast-baited trap in a week, larvae will start appearing in the fruit. At this point, scouting for spotted wing drosophila should be a high priority for growers who are harvesting berries. A seven-day spray schedule of an appropriate insecticide should provide adequate control of the flies once adults or larvae are found in the planting. (See the New England Small Fruit Management Guide for more information and details.) Should temperatures cool down and rain move into the state, it is likely that populations will increase quickly. This will put increased pressure on any ripening fruit remaining, and more frequent sprays may become necessary to prevent infestations.

Town Spotted Wing Drosophila weekly trap catch 7/22/16 Spotted Wing Drosophila weekly trap catch 7/29/16
Limington 41 83
Limerick 0 0
Springvale 0 3
Wells 1
Cape Elizabeth 0 0
Bowdoinham 17
Dresden 2 2
Freeport 3
Buxton 2 1
Mechanic Falls 0 0
Monmouth 0 0
Fayette 3
Wales 0

 

David T. Handley
Vegetable and Small Fruit Specialist

Insects in Spotted Wing Drosophila Trap

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

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

 

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

Other IPM Web Pages:
Michigan State University
Pennsylvania State University
University of New Hampshire

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.

Sweet Corn IPM Newsletter No. 6 – August 1, 2016

August 1st, 2016 2:43 PM

Sweet CornSweet Corn IPM Newsletter No. 6 – August 1, 2016
Click on photos to enlarge.

CORN EARWORM THREAT REMAINS LOW

Fall Armyworm Numbers Very High at Some Sites, Absent at Others

SITUATION
More hot and dry weather has created drought conditions in much of the state, especially in southern Maine. Cornfields that can be irrigated are doing very well, but non-irrigated fields are starting to suffer. Harvest will soon be in full swing in southern Maine. The pest situation continues to be very moderate for this time of the season, with nearly all of the pressure coming from fall armyworm, in both silking and pre-tassel corn; but some sites still have no pest threats.

European corn borer: Very low moth counts continued this week, although one site in Palmyra did exceed the 5-moth threshold for silking corn and a spray was recommended. In some years we do see a second generation of European corn borer emerge late in the season in southern Maine, but it doesn’t typically appear until September. European corn borer feeding damage was also very light this week, and no fields exceeded the 15% pre-tassel threshold.

Corn earworm: Moth counts remain very low for this time of the season. Sprays on silking corn have mostly been limited to protecting against fall armyworm and European corn borer where those have been in higher numbers. Moths were caught in seven locations this week, and all but one of those had single moths, which does not trigger a protective spray. Two moths were caught in Biddeford, placing that site on a 6-day interval for all silking corn.

Fall armyworm: Moth catches continue to be high in some sites, but low in others. It appears to be the major threat to silking corn for most locations at this time. Sprays for fall armyworm on silking corn were recommended in Biddeford, Bowdoinham, Cape Elizabeth, Dayton, Lewiston, Monmouth, New Gloucester, Nobleboro, Sabattus and Wells. As expected, feeding damage was more widely observed this week, but only exceeded the 15% feeding injury threshold at one Wells site.

Fall Armyworm on Corn Silk

Fall Armyworm on Corn Silk, photo by David Handley

Aphids on Corn Ear

Aphids on Corn Ear, photo by David Handley

Corn leaf aphids: Just a reminder that these insects often infest corn plants during dry spells, especially in fields that have not recently been sprayed for other pests. Colonies of bluish-green aphid can cover tassels, stalks and husks. Their waste encourages the dark, slimy, sooty mold fungus, which covers the surface of the husks. Sprays for corn earworm usually control aphids.

Spotted wing drosophila: We are catching low levels of flies in most locations this week, but only in high enough numbers at a site Limington to raise concern. We expect populations to reach damaging levels in southern Maine over the next few weeks, especially if we have some wet weather. Once we start catching 4 or more flies per week, we’ll recommend berry growers begin spraying raspberries and blueberries to protect against spotted wing drosophila infestation. For more information visit our Spotted Wing Drosophila blog.

Female Spotted Wing Drosophila

Female Spotted Wing Drosophila, photo by Christina Hillier

Two Squash Vine Borer Moths

Two Squash Vine Borer Moths, photo by Jeffrey Hahn, Univ. of Minnesota Extension

Squash vine borer alert! We continue to catch high numbers of squash vine borers in pheromone traps in southern and mid-state Maine. Counts were over the 5 moths per week spray threshold in Biddeford, Hollis, New Gloucester, and Oxford. Be alert for squash vine borer symptoms and protect squash plants if moths or damage are seen. See the 2016-2017 New England Vegetable Management Guide for control options.

Sincerely,

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

Sweet Corn IPM Weekly Scouting Summary

Location CEW
Moths
ECB
Moths
FAW
Moths
%Feeding
Damage
Recommendations / Comments
Biddeford 2 0 35 7% 6-day spray interval on silking corn for CEW
Bowdoinham 0 0 5 6% One spray for FAW on silking corn
Cape Elizabeth I 0 0 42 2% One spray for FAW on silking corn
Cape Elizabeth II 0 0 26 14% One spray for FAW on silking corn
Charleston 0 3 0 0% No spray recommended
Dayton 1 0 11 1% One spray for FAW on silking corn
Hollis 1 0 0 1% No spray recommended
Farmington 0 0 0 1% No spray recommended
Garland 0 0 0 2% No spray recommended
Levant 0 0 2 1% No spray recommended
Lewiston I 1 0 35 0% One spray for FAW on silking corn
Lewiston II 0 0 11 2% One spray for FAW on silking corn
Livermore Falls 0 0 0 0% No spray recommended
Monmouth 0 0 3 2% One spray for FAW on silking corn
New Gloucester 0 0 10 1% One spray for FAW on silking corn
Nobleboro 1 0 13 0% One spray for FAW on silking corn
No. Berwick 0 2 1 0% No spray recommended
Oxford 0 0 1 0% No spray recommended
Palmyra 0 5 0 1% One spray for ECB on silking corn
Poland Spring 0 2 1 1% No spray recommended
Sabattus 0 0 4 0% One spray for FAW on silking corn
Wales 1 0 0 0% No spray recommended
Warren 1 3 0 3% No spray recommended
Wells I 0 0 0 22% One spray for ECB+FAW on pre-tassel corn
Wells II 0 0 35 1% One spray for FAW on silking corn

CEW: Corn earworm (Only fresh silking corn should be sprayed for this insect.)
ECB: European corn borer
FAW: Fall armyworm

Corn Earworm Spray Thresholds for Pheromone Traps

Moths caught per week Moths caught per night Spray interval
.0 to 1.4 0.0 to 0.2 No spray
1.5 to 3.5 0.3 to 0.5 Spray every 6 days
3.6 to 7.0 0.6 to 1.0 Spray every 5 days
7.1 to 91 1.1 to 13.0 Spray every 4 days
More than 91 More than 13 Spray every 3 days

Thresholds apply only to corn with exposed fresh silk. Lengthen spray intervals by one day if maximum daily temperature is less than 80°F.

European Corn Borer Thresholds
Whorl stage: 30% or more of plants scouted show injury.
Pre-tassel-silk: 15% or more of plants scouted show injury.
Silk: 5 or more moths caught in pheromone traps in one week.

IPM Web Pages:
UMaine Cooperative Extension IPM
Penn State Sweet Corn IPM
UMass Extension IPM Programs

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.

Published and distributed in furtherance of the Acts of Congress of May 8 and June 30, 1914, by the University of Maine Cooperative Extension, the Land Grant University of the State of Maine and the U.S. Department of Agriculture cooperating. Cooperative Extension and other agencies of the U.S.D.A. provide equal opportunities in programs and employment.