Archive for the ‘News’ Category

Sweet Corn IPM Newsletter No. 3 – July 10, 2014

Thursday, July 10th, 2014

Sweet Corn

Sweet Corn IPM Newsletter No. 3 – July 10, 2014

Click on photos to enlarge.

FALL ARMYWORM, CORN EARWORM THREATEN SILKING CORN

Late Blight Alert for Potatoes and Tomatoes!

SITUATION
Last weekend’s storm will likely increase insect activity by bringing up moths from the south. Fortunately, the winds were not strong enough to cause widespread lodging in cornfields. More fields are coming into silk as the warm temperatures continue to push growth.  More silking fields are now on a spray regime for corn earworm and/or fall armyworm. The first indication of late blight in Maine was found this week in a potato field in Buxton.

European Corn Borer Larvae on Pre-tassel Stage Corn

European Corn Borer Larvae on Pre-tassel Stage Corn, photo by David Handley

European corn borer:  Moth catches were higher in some locations this week but continue to be erratic. Silking fields in Cape Elizabeth and Sabattus were over the threshold of 5 moths per week in traps, and a spray for silking corn was recommended. European corn borer feeding damage was over threshold in pre-tassel to tasseling fields in Biddeford, Bowdoinham, Lewiston and Sabattus this week. Remember that sprays applied at pre-tassel tend to be more effective than whorl or tassel stage sprays, because the larvae are usually more exposed.

Corn earworm:  The impact of the tropical storm does not yet seem to be showing up in moth counts. Moths were higher in one Cape Elizabeth location and more sights are now catching their first moths, including our more northern sites, but there has not yet been a large bump in trap captures. A 6-day spray interval was recommended for early silking fields in Dayton, New Gloucester and one Lewiston site. A 4-day spray interval was recommended for one silking field in Cape Elizabeth.

Fall armyworm:  Moth counts were up significantly in some locations while others still have yet to catch their first fall armyworm.  Fields in Cape Elizabeth, New Gloucester and Lewiston were over the threshold of 3 moths per week in silking corn. However, these fields were also on a spray regime for corn earworm, so no additional sprays should be needed. The first feeding damage on plants from fall armyworm was noted this week in fields in Biddeford and Lewiston. Although not yet threatening alone, when combined with European corn borer damage the total feeding exceeded the 15% threshold.

Fall Armyworm Moths

Fall Armyworm Moths (female right, male left), photo by James Dill

Two Squash Vine Borer Moths

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

Squash vine borer moths were caught in pheromone traps in North Berwick, Biddeford, Dayton and New Gloucester this week. The threshold of five moths per week was exceeded in North Berwick, Wells, Dayton and Biddeford. This pest threatens summer squash, winter squash and pumpkins. Unlike many moths, squash vine borer moths fly during the day. They are black and orange and resemble wasps. The moths lay eggs at the base of squash plants. The larvae bore into the base of the plants, causing vines to wilt and eventually collapse. See the 2014-2015 New England Vegetable Management Guide for control options.

Late Blight on Potato Leaf

Late Blight on Potato Leaf, photo by James Dill

Late Blight Alert! The first symptoms of late blight were found in a potato field in Buxton this week. This devastating disease of tomatoes and potatoes spreads via spores under warm, wet conditions. Growers should take precautions by applying preventative fungicides. See our publications website and the 2014-2015 New England Vegetable Management Guide for management options.

Sincerely,

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

Sweet Corn IPM Weekly Scouting Summary

Location CEW
Moths
ECB
Moths
FAW
Moths
%FeedingDamage Recommendations / Comments
Biddeford 1 3 2 40% One spray recommended for ECB + FAW
Bowdoinham 0 3 0 22% One spray recommended for ECB
Cape Elizabeth I 0 5 0 5% One spray recommended for ECB on silking corn
Cape Elizabeth II 8 3 12 1% 4-day spray interval recommended on all silking corn
Charleston 0 0 0 0% No spray recommended
Dayton I 2 0 0 6-day spray interval recommended on all silking corn
Dayton II 2 0 0 9% 6-day spray interval recommended on all silking corn
Farmington 1 1 1 12% No spray recommended
Garland 1 6 1 0% No spray recommended (no silking corn)
Levant 0 4 1 0% No spray recommended (no silking corn)
Lewiston I 1 1 0 0% No spray recommended
Lewiston II 2 0 3 20% 6-day spray interval recommended on all silking corn
Livermore Falls 1 0 0 3% No spray recommended
New Gloucester 2 4 6 1% 6-day spray interval recommended on all silking corn
No. Berwick 0 0 1 10% No spray recommended
Oxford 0 1 0 5% No spray recommended
Palmyra 0 15 0 1% No spray recommended (no silking corn)
Sabattus 0 29 0 34% One spray recommended for ECB on silking corn
Wales 0 2 0 3% No spray recommended
Warren 0 0 0 13% No spray recommended
Wells I 1 0 0 5% No spray recommended
Wells II 0 0 1 0% No spray recommended

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:
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.

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.

Maine State Pomological Society Summer Meeting and Orchard Tour – July 23, 2014

Monday, July 7th, 2014

Apples

Maine State Pomological Society Summer Meeting and Orchard Tour

Please visit the UMaine Cooperative Extension Tree Fruit website for more information on the Maine State Pomological Society Summer Meeting and Orchard Tour, scheduled for Wednesday, July 23, 2014 at a Cooper Farms orchard located in Hartford, Maine.

Sweet Corn IPM Newsletter No. 2 – July 3, 2014

Thursday, July 3rd, 2014

Sweet Corn

Sweet Corn IPM Newsletter No. 2 – July 3, 2014

Click on photos to enlarge.

CORN BORER, CORN EARWORM AND FALL ARMYWORM MOTHS ACTIVE

Silking Corn Needs Protection in Early Fields

SITUATION
Cornfields are developing fast with the onset of warm (very warm) temperatures this week. Several early plantings are now in silk while others are coming into tassel. Any showers that arrive this weekend will be welcomed in early fields where conditions are very dry. All of the major corn pests have arrived and are active in cornfields in much of the state. These are especially a threat to early silking fields, which growers often spray lightly, if at all, assuming the major pests are not yet present in damaging numbers.

European corn borer:  Moth catches are spotty around the state this week with about half of the sites now catching moths. A field in Nobleboro was over threshold of 5 moths per week in an early field of silking corn. Another field in Warren was also over the threshold, but does not yet have corn in silk, so no spray was recommended. European corn borer feeding damage was over the 15% threshold in pre-tassel fields in Biddeford, Bowdoinham, New Gloucester, Sabattus, Livermore Falls and Nobleboro.

European Corn Borer Moth

European Corn Borer Moth, photo by David Handley

Corn Earworm Moth

Corn Earworm Moth, photo by David Handley

Corn earworm:  We are now finding corn earworm moths in most of our monitoring sites. Numbers are still low, and most fields do not yet have any silking corn that could be threatened by this pest. When more than one corn earworm moth is found at a site, all silking corn in the fields should be protected with a spray. Additional sprays are based on the average number of moths caught per week or per night (see table below). Only one field in Cape Elizabeth had moths over threshold and early silking corn. A 5-day spray interval was recommended at that location, based on a weekly moth catch of 4.

Male Fall Armyworm Moth

Male Fall Armyworm Moth, photo by David Handley

Fall armyworm:  Moths have arrived in many of the fields monitored this week, indicating that cornfields will soon start showing feeding damage from larvae. Fall armyworm caterpillars leave large ragged holes in the corn leaves and lots of sawdust-like waste within the whorl and developing tassels. We found two fields showing feeding damage this week. In silking fields, fall armyworm larvae may enter the ears through the silk channel, leaving little visible damage to the plant. For that reason, when more than 3 fall armyworm moths are caught in pheromone traps in a week a spray is recommended for all silking corn in a field. Only one field in Cape Elizabeth was over the threshold for silking corn this week. However, that same field was also on a spray schedule for corn earworm in silking corn, so no additional sprays should be required to control fall armyworm.

Japanese beetles should soon be appearing in southern and mid-state areas. These insects often find their way into cornfields and feed on the silks of developing ears, causing poor tip fill. Sprays for corn earworm (except Bt’s) will often control Japanese beetle as well.

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:  The first capture of a spotted wing drosophila in Maine was reported this week from a wild blueberry field in Blue Hill. These small fruit flies can cause serious fruit losses in raspberries, blueberries and other soft fruits. The flies will only attack fruit that has begun to ripen, and we don’t expect populations to reach damaging levels for a few weeks. For more information visit our website: http://extension.umaine.edu/highmoor/news-events/.

Sincerely,

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

 

Sweet Corn IPM Weekly Scouting Summary

Location CEW
Moths
ECB
Moths
FAW
Moths
%Feeding
Damage
Recommendations / Comments
Biddeford 0 4 2 25% One spray recommended for ECB on pre-tassel corn
Bowdoinham 2 0 0 28% One spray recommended for ECB on pre-tassel corn
Cape Elizabeth I 1 0 0 0% No spray recommended
Cape Elizabeth II 4 0 15 0% 5-day spray interval recommended on all silking corn
Dayton 0 0 0 0% No spray recommended
Dayton II 1 0 2 2% No spray recommended
Farmington 0 1 0 3% No spray recommended
Lewiston 4 2 1 1% No spray recommended (no silking corn)
Lewiston II 0 4 1 4% (no silking corn)
Livermore Falls 0 0 0 15% One spray recommended for ECB on pre-tassel corn
Monmouth 0 0 0 0% No spray recommended
New Gloucester 1 0 1 1% No spray recommended
Nobleboro 1 10 0 18% One spray recommended for ECB on pre-tassel-silk corn
No. Berwick 1 0 1 40% One spray recommended for ECB on pre-tassel corn
Oxford 1 1 0 4% No spray recommended
Sabattus 1 0 0 38% One spray recommended for ECB on pre-tassel corn
Wales 0 0 0 8% No spray recommended
Warren 0 24 0 0% No spray recommended (no silking corn)
Wells I 0 0 0 0% No spray recommended
Wells II 0 0 1 0% No spray recommended

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:
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.

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.

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/

Handley Talks About Maine Strawberry Crop for Press Herald Article

Friday, June 27th, 2014

David Handley, a University of Maine Cooperative Extension specialist of vegetables and small fruits at UMaine’s Highmoor Farm in Monmouth, was interviewed for a Portland Press Herald article about this year’s strawberry season. Handley said conditions have been ideal starting last fall and continuing through this week, when many farms in the Augusta area are opening for picking. He said the last two years the crop has come in early, but this year is a more normal ripening schedule. He said he expects the best strawberry crop Maine has had in three or four years.

Sweet Corn IPM Newsletter No. 1 – June 27, 2014

Friday, June 27th, 2014

Sweet Corn

Sweet Corn IPM Newsletter No. 1 – June 27, 2014

Click on photos to enlarge.

2014 SWEET CORN PEST SEASON BEGINS!

European Corn Borer Moths Active, Larvae Feeding in Early Corn

The 2014 University of Maine Cooperative Extension Integrated Pest Management (IPM) program for sweet corn is underway. More than twenty volunteer farms are serving as pest monitoring and demonstration sites, with fields in North Berwick, Wells, Dayton, Cape Elizabeth, New Gloucester, Poland Spring, Auburn, Lewiston, Sabattus, Nobleboro, Warren, Monmouth, Wales, Wayne, Oxford, Farmington, Levant, Stillwater, Garland and East Corinth. Pheromone traps have been set up at these farms to monitor the adult (moth) stages of European corn borer, corn earworm and fall armyworm, and we have begun scouting the fields for feeding injury by insect larvae. The information collected at these sites along with management recommendations will be shared every week during the season through this newsletter and blog. If you would prefer to receive this newsletter via e-mail, give us a call at 207.933.2100 or send an e-mail message to: pamela.stpeter@maine.edu.

European Corn Borer Scouting

European Corn Borer Scouting, photo by David Handley

SITUATION
Farmers with well-drained fields were able to get some early plantings going in spite of a rather cool, wet start to the season. Early seedings started under clear plastic or fabric row covers are now in the pre-tassel to tassel stage, with one southern field already starting to show some silk. In spite of the wet conditions during the spring, some fields are starting to get a bit dry, so the recent rain was quite welcome. Warmer weather predicted for next week should speed up plant development. European corn borer moths have been active in some fields, as evidenced by some light feeding damage we have seen in some pre-tassel fields this week.

European corn borer:  We have set up pheromone traps for European corn borer this week, and we’ll start reporting on moth activity in the next issue. We found some feeding injury and very small larvae in pre-tassel fields this week, indicating that moths are now laying eggs on the undersides of corn leaves. The egg masses are small and look like overlapping fish scales. European corn borer overwinters in Maine, and is usually the first pest to become a significant problem. To monitor corn borer, we scout 100 corn plants in each field, examining twenty plants in a row at five different locations. This provides a good estimate of the total amount of injury in a field.

European Corn Borer Moth

European Corn Borer Moth, photo by David Handley

European Corn Borer Damage on Pre-tassel Stage corn

European Corn Borer Damage on Pre-tassel, photo by David Handley

In the early stages, European corn borer feeding damage looks like small “pinholes” in the leaves. Whorl stage corn only needs to be sprayed if fresh feeding injury is found on 30% or more of the plants scouted in a field. Once the corn reaches the pre-tassel stage, the control threshold is lowered to 15% because larvae feeding on the later stages are more likely to move into the ears. On the tassels, feeding damage first appears as chewing and brown waste found in the small florets. After the tassel has emerged from the stalk, the larvae chew into the stalk just below it, often causing the tassel to fall over. Sprays during the pre-tassel stage, when both moths and larvae are present, reduce the opportunity for larvae to move into the stalks and ears of the plant. Once the larvae are in the stalks they are protected from sprays. Good spray coverage of the entire plant provides the most effective kill of larvae as they move from one part of the plant to another. Rotating the type of insecticide used also improves control. Materials registered for controlling European corn borer include Bacillus thuringiensis products (XenTari®, Dipel DF®), Avaunt®, Coragen®, Warrior®, Lannate®, Baythroid®, Asana®, Radiant®, Delta Gold®, Mustang®, Sevin XLR® and Larvin®. We found corn borer feeding injury in pre-tassel fields in Sabattus, Farmington, Livermore Falls, New Gloucester and Nobleboro this week; but only the field in Nobleboro exceeded the injury threshold. Once corn reaches the silk stage, sprays may be based on the number of corn borer moths caught in pheromone traps rather than feeding injury. European corn borer moths will lay eggs on flag leaves of silking corn, and the larvae can move into the ears without leaving visible feeding injury that would be noticed when scouting. If more than five moths are caught during a week in a field with silking corn, a spray is recommended. Varieties of corn genetically modified to produce the Bt toxin (e.g. Bt corn, Attribute® varieties), should not need to be sprayed to control European corn borer.

Corn earworm:  Pheromone traps are now set up around the state to monitor the arrival of corn earworm. Corn earworm generally appears in Maine in early July, but the actual date varies greatly. The arrival of this pest is only a concern for fields with corn in the silk stage. Fields not yet in silk do not need to be protected from corn earworm. When corn earworm moths start being caught at a site, all silking corn in the fields should be protected with a spray. These moths lay eggs on the fresh silks and the larvae move directly into the ears of corn. When corn earworm moths cannot find silking corn to deposit their eggs on, they may lay eggs on the leaves of younger corn. The larvae will feed on the foliage and tassels, similar to armyworm, until the ears become available. When larvae are found feeding on younger corn, the damage is accounted for, along with any borer or armyworm damage, to determine if a spray is warranted.

Corn Earworm Moth

Corn Earworm Moth, photo by David Handley

Fall Armyworm Moths

Fall Armyworm Moths (female right, male left), photo by James Dill

Fall armyworm:  This is usually the last serious corn insect pest to arrive in Maine. The moths must fly in from southern over-wintering sites, and tend to lay their eggs on the youngest corn available. When the larvae hatch, they chew large, ragged holes in the leaves, and may bore into developing ears. Larvae may also move into the ears through the silk channel, behaving similarly to corn earworm. Pheromone trap catches will indicate if there is a threat to silking corn. However, corn will usually be on a spray program for corn earworm when fall armyworm is present, and both insects would be controlled.

Harstack Trap

Harstack Trap, photo by David Handley

Do-It-Yourself IPM:  To get the most accurate information about the pest situation on your farm you should monitor the fields yourself on a regular basis. Pheromone traps and lures are available that can give you an accurate, early warning of the arrival of all of the major insect pests. Traps and lures can be purchased from pest management supply companies such as Gempler’s (1.800.382.8473) or Great Lakes IPM (517.268.5693).

To learn more about IPM scouting techniques, insect identification and control thresholds, order the fact sheet Managing Insect Pests of Sweet Corn available from the University of Maine Cooperative Extension. Color pictures are provided to help with insect identification, and a chart with spray thresholds is supplied to post near your sprayer for easy reference. You can download a copy from the UMaine IPM website or call the Pest Management Office at 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/

Sincerely,

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

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.

Strawberry IPM Newsletter No. 5 – June 20, 2014

Friday, June 20th, 2014

StrawberriesStrawberry IPM Newsletter No. 5 – June 20, 2014

Click on photos to enlarge.

HARVEST STARTS IN SOUTHERN MAINE

Spider Mites and Leaf Diseases Active

Situation:  Strawberry picking is underway in southern Maine this week, with many farms opening for pick-your-own customers this weekend. Overall, the crop looks good to very good, in spite of some winter injury and a cool, wet start to the season. It also looks as though we will have good weather for opening weekend customers. The Strawberry IPM Newsletter, will take a couple of weeks off while we enjoy the harvest and will be back with our Renovation Issue in July.

Large Tarnished Plant Bug Nymph

Third Instar Tarnished Plant Bug Nymph, photo by David Handley

Tarnished plant bug nymphs were absent in many fields this week and in low numbers wherever they were found. Only one field exceeded the control threshold of 4 flower clusters infested with nymphs out of 30 sampled. If you still have blossoms remaining in your field, it is important to keep scouting for nymphs into the green fruit stage to prevent injury.

Two-spotted spider mites:  Two fields we scouted this week were over the control threshold of 25% of leaves infested; but most fields had very few, if any, mites present. As drier weather sets in, mite populations will likely begin to increase. Continue scouting for mites during the summer after bed renovation, to prevent a build up that could weaken the plants during flower bud development.

Two-spotted Spider Mites

Two-spotted Spider Mites, photo by David Handley

Strawberry Root Weevil Grub

Strawberry Root Weevil Grub, photo by David Handley

If black vine weevils or strawberry root weevils are a problem in a strawberry field that you would like to carry over, bifenthrin (Brigade®) can be applied to control the beetles when their feeding is noticed (usually until mid- to late-July). Grubs are now beginning to pupate in the soil, and the adult weevils will begin to emerge in a few weeks. Look for notching along the leaf edges and the presence of the black or brown snout beetles during the evening. Applications should be made at night when these insects are active, and the highest allowable rate of the insecticide should be used.

Powdery Mildew

Powdery Mildew, photo by David Handley

Leaf Spot on Strawberry Plant

Leaf Spot, photo by David Handley

Diseases:  Dry weather predicted for the upcoming week should provide some relief from the threat of fruit rots, including gray mold and leather rot. However, foliar diseases, including powdery mildew and leaf spot can continue to flourish under drier conditions if infections have already occurred. If you still have significant bloom remaining in the field, you may still need to apply a fungicide to protect against gray mold, especially if rain is predicted in your area, or you plan to overhead irrigate the planting.

Keep an eye out for anthracnose fruit rot as berries begin to ripen in the field.  Infected fruit show sunken patches of brown or black. Whole fruit may suddenly turn soft or dry up to blackened mummies. This is usually a problem when fields have standing water present and warm temperatures. I haven’t seen anthracnose in the fields I have visited so far, but be aware that this could still become a problem. Effective fungicides include Cabrio® and Abound®.

Spraying Pesticides on Raspberries Using Backpack

Spraying Pesticides on Raspberries, photo by Jill Stanley

Important Reminder for Pesticide Users
Fruit, vegetable or grain growers who use general use (over-the-counter) pesticides and annually sell more than $1,000 of plants or plant products intended for human consumption will be required to have an Agricultural Basic Pesticide Applicator License by April 15, 2015. In the past, only farmers using restricted use pesticides were required to have a pesticide applicators license. The new law extends the licensing requirement to all commercial growers who use pesticides. Training and testing sessions for unlicensed farmers will be held across the state this fall and winter. For more information contact the Pest Management Office at 1.800.287.0279.

Review:  Keeping Strawberries Fresh for Market
If you‘re bringing fruit to market, make sure that it arrives in the best condition possible. Strawberries cool most efficiently if harvested early in the morning before they build up field heat. Place fruit into refrigerated storage quickly and keep it out of direct sunlight. Fruit should be stored at 32°F and 95% relative humidity. Cold air should be moved through the boxes or flats of fruit with a circulating fan and/or exhaust fan to cool most efficiently. Temperatures lower than 32°F may freeze the fruit and ruin its fresh quality. A small, well-insulated building cooled with air conditioners and fans can provide effective temporary storage for strawberries. If you don’t have refrigeration facilities, keep the fruit as cool as possible by harvesting when air temperatures are cool, and keeping it out of direct sunlight. Transport the fruit to market as quickly as possible, and harvest only what you think you can sell in a day.

Strawberry Harvest

Strawberry Harvest, photo by David Handley

Annual Pre-Harvest Checklist for Pick-Your-Own
It’s that time again! As harvest approaches, we like to remind you to take a moment and make sure that your farm is prepared to give your customers an enjoyable experience. Take a look at our checklist and evaluate your customer readiness.

√  Signs to the farm are neat and easy to read.

√  There is easy access to the fields and plenty of parking.

√  Someone is ready to greet customers and offer parking instructions and directions to the field.

√  Access to the field is free of hazards.

√  Transportation is provided for the elderly and disabled.

√  The rules regarding picking are clearly posted.

√  Someone is in the field to show customers where to pick and to answer questions.

√  There are plenty of picking containers available.

√  Clean restroom and hand washing facilities are available.

√  Someone is available to help customers carry fruit out of the field.

√  The checkouts are fast and efficient.

√  Beverages are available.

√  Shade and seats are available for customers wanting to rest.

√  The help are friendly and knowledgeable.

A friendly, clean, and organized atmosphere will leave a lasting impression on your customers, encouraging them to come back and to recommend your farm to their friends.

Websites Worth Visiting
If you are looking for information to help diagnose a problem in your strawberries or need a recommendation for a control strategy, the 2013-2014 New England Small Fruit Management Guide is available online. You should also check out Cornell University’s Berry Diagnostic Tool online.

Sincerely,

David T. Handley
Vegetable & Small Fruit Specialist

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

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.  A Member of the University of Maine System.

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.

Drummond Talks to BDN About Blueberry, Bee Research

Tuesday, June 17th, 2014

Frank Drummond, an entomology specialist with the University of Maine Cooperative Extension and a UMaine professor of insect ecology, spoke to the Bangor Daily News about a five-year, $3.5 million research project on the role bees play in blueberry production. Drummond is leading the project that involves biologists, economists, anthropologists and graduate students from UMaine, as well as researchers from other states. Drummond said renting commercial beehives is, on average, the most expensive production cost for Maine’s blueberry growers. The project aims to study the role native bees play in blueberry pollination, the status of native bee populations, and which species of bees are best for adequate pollination. “The whole purpose of this project is to look at what are some of the best pollination strategies that growers might be able to use,” he said. The project also includes outreach to blueberry growers in the form of workshops hosted by Drummond to teach growers about pollination.

Strawberry IPM Newsletter No. 4 – June 13, 2014

Friday, June 13th, 2014

StrawberriesStrawberry IPM Newsletter No. 4 – June 13, 2014

Click on photos to enlarge.

EARLY FIELDS GETTING READY FOR HARVEST

Tarnished Plant Bugs, Spider Mites and Leaf Diseases Active

Situation:  Strawberry development continues to be slow, as we can’t seem to string together more than a couple of warm days before the cool damp weather creeps back in. Despite the clouds, many fields are starting to get a bit dry; although rain predicted for this weekend may bring those fields some needed moisture. Overall, most fields look very good, with good plant vigor and fairly heavy bloom. Turn out for our twilight meeting at Fairwinds Farm in Bowdoinham was very good, and we thank Pete and Cathy Karonis for their hospitality. Many of the strawberry growers there were hoping to start picking next week and perhaps opening for pick-your-own next weekend. It looks like we’ll have a good crop for July 4th.

Strawberry bud weevil or “clipper” is very active in late flowering varieties and raspberries this week. Most early and mid-season varieties are now beyond the point at which clippers can cause significant damage. Two fields scouted this week were over threshold for clipped buds. Remember that clippers will move onto raspberries to clip flower buds after strawberry bloom.

Clipper Beetle on Strawberry Blossom

Clipper Beetle on Strawberry Blossom, photo by David Handley

First Instar Tarnished Plant Bug Nymph

First Instar Tarnished Plant Bug Nymph, photo by David Handley

Tarnished plant bug nymphs are present in most fields this week, but in most cases were not over the threshold of 4 flower clusters infested with nymphs out of 30 sampled. Most of the nymphs found were still in the very small, bright yellow-green phase. It is important to keep scouting for nymphs through the bloom period and into the green fruit stage because feeding damage can still occur, causing misshapen, seedy berries.

Two-spotted spider mites were present in most fields scouted this week but, with one exception, they were well under the threshold of 25% of leaves infested. Cool, damp weather generally keeps mite populations in check naturally, but they can increase rapidly under hot, dry conditions, so it is important to keep scouting for them.

Cyclamen Mite Damage

Cyclamen Mite Damage, photo by David Handley

Cyclamen mites:  We continue to find fields with cyclamen mite infestations. Usually symptoms are first noticed in beds that are two or three years old.   Infested plants show weak growth and yellow, crinkled leaves. The flower stems are small and short and the petals are deformed and sometimes look pink.  The symptoms can be confused with winter injury, herbicide injury or virus infection. Cyclamen mites reside on undeveloped leaves and flower clusters down within the crown of the strawberry plants, and can be very hard to see, even with magnification. Miticide applications must be applied with lots of water (40-100 gals./acre) to be sure that the material reaches the mites.

Sap beetles sometimes become a problem when fruit starts to ripen. The 1/8-inch long, dark brown beetles chew small holes in ripening fruit, similar to slug injury. They may be seen in the holes they’ve chewed into ripe fruit, but often drop to the ground when disturbed. The best management strategy for sap beetles is good sanitation. Keep the field free of overripe fruit by picking often and thoroughly. Insecticide sprays for this pest can be effective, but should be a last resort during the harvest period. Brigade®, Assail® Dibrom® and PyGanic® are registered for control of sap beetles with pre-harvest intervals ranging from 12 to 24 hours. Read the product label carefully for this and other application instructions and restrictions.

Slug on Strawberry

Slug on Strawberry, photo by James Dill

Slugs may also start feeding on strawberries as they start to ripen. Moist conditions and mulch encourage the presence of slugs. They feed at night, leaving large holes and tunnels in ripening fruit and shiny slime trails on the leaves. Baits such as Deadline® and Sluggo® offer some control of slugs, and should be used prior to fruit ripening. Avoid contacting the developing fruit with the bait. Pay close attention to label instructions and precautions. Slugs overwinter in the egg stage, so baits applied to the fields in mid-September can effectively reduce egg-laying.

Diseases:  Many fields are now past the most susceptible bloom stage for primary infection by Botrytis spores. Fungicides applied during bloom should provide adequate protection against gray mold unless fields get lots of rain post-bloom. If more than one inch of rain has fallen since your last fungicide application, it is likely that the fruit are no longer protected, and another application may be warranted.

Leather rot (Phytopthora cactorum):  Most fields have dried out very well over the past week, reducing the chance of leather rot infections. If you have standing water in your fields during the bloom or early fruit development period, you may want to consider a fungicide application to prevent leather rot. Remember that fungicides applied for gray mold are generally not effective for leather rot. Aliette®, Agri-Phos® or Phostro® are considered most effective.

Powdery mildew:  Warmer, humid weather has increased the symptoms of powdery mildew in fields this week. Many plants are starting to show red streaks on the leaf and flower stems, upward curling leaves, and white, powdery growth on the leaf undersides. Keep an eye out for leaf cupping in your fields and, if you need to apply another fungicide for gray mold, add a material that will also provide control of powdery mildew, such as Pristine®, Topsin-M®, or captan.

Leaf Spot

Leaf Spot, photo by David Handley

Leaf Scorch

Leaf Scorch, photo by David Handley

Leaf spot infections are becoming more common in strawberry fields this week. The spots usually appear on older leaves first, as small purple or red spots with white centers. Leaf scorch has also been noted in a couple of fields. The spots are smaller in the case of scorch, and lack the white centers. Spots may coalesce to turn the leaves purple and brown, leading to the death of the leaf and weakening of the plant. Many strawberry varieties have at least partial resistance to leaf spot and leaf scorch. Fungicides registered for leaf spots include captan, Topsin-M®, Cabrio®, and Pristine®.

Bird Damage on Strawberry

Bird Damage on Strawberry, photo by David Handley

Birds, specifically cedar waxwings, will soon be moving into fields to feed on ripening fruit. Waxwings often destroy many of the early ripening fruit, despite our best efforts to scare them off. Only by keeping a near constant presence in the field and eliminating roosting sites can you keep them at bay. They are often discouraged once people start to occupy the fields much of the day to harvest. Cedar waxwings are songbirds and are protected by law. They should not be killed. However, the U.S. Fish and Wildlife Service may issue permits for killing birds if they receive a recommendation for such a permit from the Maine Wildlife Services Office (part of the USDA Animal and Plant Health Inspection Service) in Augusta, along with an application from the grower. There is a $50 fee for the application, and it may take over a month for the permit to be processed. However, the permit is good for one year; so if you have problems this season, you may consider applying for a permit this winter, which would allow you the option to kill birds, if necessary, next season. The Wildlife Damage Office has recommendations for managing birds in crops, and also has some control options available through their office. For more information on permits or bird control contact the office in Augusta at 207.629.5181. The office is located in the Capital West Business Center, 79 Leighton Road in Augusta.

Sincerely,

David T. Handley
Vegetable & Small Fruit Specialist

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

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.  A Member of the University of Maine System.

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.

Handley Offers Tips on Growing Berries for Press Herald Article

Wednesday, June 11th, 2014

David Handley, a University of Maine Cooperative Extension specialist of vegetables and small fruits at UMaine’s Highmoor Farm in Monmouth, was interviewed for a Portland Press Herald article about the best methods for growing native berries. Handley shared tips for successfully growing strawberries, blueberries, raspberries and blackberries at home.