Strawberry IPM Newsletter No. 3 – May 28, 2015

May 29th, 2015 12:05 PM

StrawberriesStrawberry IPM Newsletter No. 3 – May 28, 2015

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STRAWBERRY INSECT PESTS NOW ACTIVE

Clippers, Tarnished Plant Bugs and Spider Mites Over Threshold this Week

Vegetable and Berry Growers Twilight Meeting
Thursday, June 11, 2015 at 5:30 p.m.
Snell Family Farm, 1000 River Road, Buxton, Maine 04093

Situation: Broad swings in temperature continue to characterize the weather, from unusually hot days to a surprise freeze in some inland towns last weekend.  Conditions also remain dry, and while that is good for reducing the chance of fungal diseases, the plants will need water soon to help size up the berries. Early varieties are at full bloom or slightly beyond in much of the state, while later varieties are now coming into bloom. Some fields may have experienced frost or freeze damage late last week as night temperatures fell dramatically, in spite of fairly windy conditions.

Strawberry bud weevil or “clipper” activity is increasing in some of the fields we’ve scouted. Clipped buds on later varieties are becoming apparent and were over the threshold (more than 1.2 clipped buds per two feet of row) in one location this week. Scout for clipped buds now in fields just coming into bloom. Once a field is in full bloom, clipper is no longer a significant threat. Insecticide options for clipper include Lorsban®, Brigade®, Bifenture®, Danitol®, Sevin® and PyGanic®.

Clipper Damage on Strawberry Plant

Clipped Flower Buds from Strawberry Clipper, photo by David Handley

Large Tarnished Plant Bug Nymph

Third Instar Tarnished Plant Bug Nymph, photo by David Handley

Tarnished plant bug activity has increased this week. We are now finding the small, yellow-green immature bugs, or nymphs, in the flower clusters. These will feed on the receptacle of the flowers, causing the fruit to have seedy ends, or “catfacing”. The nymphs are very small (2 mm) at this time and can be hard to see. It is important to scout any flowering fields for them now, as they can spread very quickly. The threshold for nymphs is 4 or more flower clusters infested per 30 sampled. Insecticide options for tarnished plant bug include malathion, Assail®, Brigade®, Bifenture®, Danitol®, and PyGanic®.

Two-spotted Spider Mites

Two-spotted Spider Mites, photo by David Handley

Two-spotted spider mites are building up in some fields, which is to be expected when we have extended warm, dry weather. Two fields have been over the control threshold of 25% or more of leaves infested. Mites will reproduce rapidly if warm conditions continue, so it is important to scout for them regularly. Chemical control options for two-spotted spider mites include Acramite®, Savey®, Zeal®, Vendex®, Oberon®, Brigade®, Danitol®, and Thionex®. Be sure to use enough liquid and pressure in the spray to get good coverage on the undersides of the leaves.

Root Weevils:  Two fields with a history of strawberry root weevil problems have had some grub activity this week. Infested plants look weak, and often wilt. There are no chemical controls registered for use within the harvest period at this point. Parasitic nematodes may be applied, but need high moisture conditions to become established and provide effective control. See the New England Small Fruit Management Guide for details.

Strawberry Rootworm Beetle

Strawberry Rootworm Beetle, photo by David Handley

Strawberry rootworm (not root weevil) adults and feeding injury have been found on strawberry leaves in some fields this spring. The adult stage of this insect is a small (1/8”) dark brown beetle. The beetles feed on strawberry leaves during the spring and late summer, causing numerous small holes in the leaves. The adults in fields now will soon lay eggs. The larvae are small grubs that feed on the roots of strawberry plants, causing them to be stunted and weak. If these beetles and/or feeding injury is prevalent in a field, a treatment is recommended. Sevin 50WP® is registered for control of this pest, and sprays targeted at other insect pests at this time may also control rootworm. Avoid spraying insecticides, especially Sevin 50WP®, during bloom, as it is highly toxic to many pollinating insects. Strawberry rootworm should not be confused with root weevil, a larger insect that causes much more serious damage when present in a field.

Spittlebug

Spittlebug, Photo by David Handley

Spittlebugs:  The frothy spittle masses on the leaf and flower stems from spittlebugs usually show up around bloom. Spittlebugs don’t pose a significant threat to the plants, but the spittle masses are a nuisance for pickers. Spittlebugs overwinter as eggs and the nymphs emerge in late May. Scouting for spittlebugs should start when the plants are at 10% bloom. Randomly inspect five, one square foot areas per field every week. Spread the leaves and inspect the crowns, leaf bases, leaf stems, and flower stems looking for the frothy spittle masses. Small, yellow-orange nymphs will be under the spittle. If the average number of spittle masses is more than two per foot, a treatment may be warranted. Spittlebugs tend to be a greater problem in weedy fields. Pesticides currently registered for spittlebug control include Provado®, Thionex®, Danitol® and Brigade®.

Diseases:  Fields in bloom should be protected against infection by spores of the gray mold fungus, Botrytis cinerea. Although the present dry conditions will likely reduce disease pressure this spring, fungicides need to be applied as protectants in case a significant moisture event occurs, causing a sudden release of fungal spores. Registered products include Topsin-M®, captan, Elevate®, Thiram®, Pristine®, Scala® and Switch®.  See the New England Small Fruit Management Guide for details.

Powdery mildew:  This foliar disease is now starting to show up on susceptible varieties. It may first appear as purple or red blotches on the leaf and flower stems. The most prominent symptom is an upward curling of the leaves and white, powdery growth on the undersides. Check your fields for leaf cupping now. Some, but not all, of the fungicide products registered for gray mold will also provide control of powdery mildew. Pristine®, Cabrio®, Topsin-M®, captan, Procure®, Torino® and JMS Stylet Oil® are registered to control powdery mildew.

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 may also be seen. 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®.

Grass control in strawberry fields:  Controlling perennial grasses in strawberry beds can be challenging. Poast®, Select 2EC® and Selectmax® 0.97EC are registered to control emerged grasses in strawberries. Often more than one application is needed to obtain satisfactory control. All of these products require the addition of a crop oil concentrate to the spray. It is important to note that these products can cause significant injury to strawberry plants if they are applied on hot, humid days, or if high temperatures occur within one or two days of application. Poast® should not be applied within 7 days of harvest. Select® and Selectmax® should not be applied within 4 days of harvest. Follow all product label instructions.

Reminder: Twilight Meeting
The University of Maine Cooperative Extension and the Maine Vegetable and Small Fruit Growers Association will hold a twilight meeting at the Snell Family Farm, 1000 River Road, Buxton, ME 04093 on Thursday, June 11 at 5:30 p.m. The Snell’s will host a tour of their farmstand, greenhouses and vegetable fields and describe their growing and marketing practices. In addition, we’ll discuss the upcoming season and pest management issues facing vegetable and berry growers this year. We anticipate that one pesticide applicator recertification credit will be awarded for the meeting.

Sincerely,

David T. Handley
Vegetable and 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.

Strawberry IPM Newsletter No. 2 – May 20, 2015

May 22nd, 2015 10:19 AM

StrawberriesStrawberry IPM Newsletter No. 2 – May 20, 2015

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STRAWBERRY PESTS OFF TO A SLOW START

No Clippers, Tarnished Plant Bugs or Spider Mites Over Threshold this Week

Vegetable and Berry Growers Twilight Meeting
Thursday, June 11, 2015 at 5:30 p.m.
Snell’s Family Farm, Buxton, Maine

Situation: It’s too hot, no wait, it’s too cold.   Great swings in temperature have been the feature this spring as we bounce from days in the 80’s to days in the 40’s, but as far as strawberry plant development is concerned most fields are about where they should be for this point in the season.   Early varieties are coming into bloom, while later varieties now have flower buds emerging from the crowns. Some inland locations have had to protect buds from frost, and may have to again over the next week; while more southern and coastal sites have, so far, not had serious frost threats.  The most common complaint among growers is the lack of rain.  While ground water levels are still in good shape for irrigation, dry fields can lead to stressed plants and nutrient deficiencies, which result in poor fruit size and quality. Once the fruit have started to develop, strawberry plants should receive one to two inches of water per week to prevent a rapid decline in fruit size after the first picking.

Twilight Meeting
The University of Maine Cooperative Extension and the Maine Vegetable and Small Fruit Growers Association will hold a twilight meeting at Snell’s Family Farm in Buxton on Wednesday, June 11 at 5:30 p.m.  John, Ramona and Carolyn Snell as well as other family members grow mixed vegetables, apples, bedding plants, cut flowers, and raspberries.  They sell their produce at their farmstand and at local farmers markets in addition to operating a large Community Supported Agriculture (CSA) program. The Snell’s will host a tour of their farmstand, greenhouses and vegetable fields and describe their growing and marketing practices.  In addition, we’ll discuss the upcoming season and pest management issues facing vegetable and berry growers this year.  We anticipate that one pesticide applicator recertification credit will be awarded for the meeting. Hold the date! We’ll give driving directions soon.

Strawberry bud weevil or “clipper” is now active in most of the fields we’ve scouted.  But so far all we have seen is feeding signs on a few open primary flowers, no clipped buds, suggesting that the adults are now just feeding on pollen and mating.  However, they will very soon start laying eggs and girdling flower buds. Given these signs, you should now start looking for clipped buds. Insecticide options for clipper include Lorsban®, Brigade®, Bifenture®, Danitol®, Sevin® and PyGanic®.

Clipper Injury

Clipper Injury, Photo by David Handley

Tarnished Plant Bug Nymph on Strawberry Blossom

Tarnished Plant Bug Nymph on Strawberry Blossom, photo by David Handley

Tarnished plant bug activity has been very low so far this season.  We have had reports of a few adults spotted in the field, but we have not yet found any nymphs, which are the more damaging stage of this insect.  The nymphs can be hard to find, especially if the plants are wet. Young nymphs are very small (2 mm), active, yellow-green insects.  It is important to scout for them regularly, as they can appear very quickly. The threshold for nymphs is 4 or more flower clusters infested per 30 sampled. Start scouting any field with open flowers now.  Insecticide options for tarnished plant bug include malathion, Assail®, Brigade®, Bifenture®, Danitol®, and PyGanic®.

Two-spotted Spider Mites

Two-spotted Spider Mites, photo by David Handley

Two-spotted spider mites have only been found in one location this week.  This is surprising given how dry it has been.  Mites typically proliferate under hot, dry conditions, and we often first find them in plantings under row covers.  But plantings that harbored a high mite population last fall are also likely to see a problem with mites in the spring.  Spider mites will reproduce rapidly under warmer temperatures, so it is important to scout for them regularly. If 25% of leaves sampled (e.g. 15 out of 60) have any mites, a spray should be applied. Chemical control options for two-spotted spider mites include Acramite®, Savey®, Zeal®, Vendex®, Oberon®, Brigade®, Danitol®, Thionex® and JMS Stylet Oil® (oils will cause plant injury if used in combination with captan or within 14 days of an application of sulfur).  Be sure to use enough liquid and pressure in the spray to get good coverage on the undersides of the leaves.

Cyclamen mites:  We have seen two fields with light symptoms of cyclamen mite injury this week.  Infested plants show weak growth and yellow, crinkled leaves. These mites are very small and reside in the crown of the strawberry plant, feeding on the developing leaves and flower buds. They are very hard to see, even with magnification. Portal®, Kelthane® or Thionex® can be effective, but must be applied in lots of water to be sure that the material is carried down into the crowns where these mites reside.   Thionex® will no longer be available for use on strawberries after July of 2016.

Cyclamen Mite Damage on Strawberry Plant

Cyclamen Mite Damage on Strawberry Plant, photo by David Handley

White Grub

White Grub, Photo by David Handley

White grubs:  There have been calls regarding white grubs in turf this week, so we should expect that we may also see injury in strawberry beds.  Infested plants are stunted and often wilt during the heat of the day. These grubs are the larvae of the Japanese beetle, European chafer and Asiatic garden beetle. They have legs and a swollen anterior (rear end).  Admire Pro® can be applied for control of white grubs in the spring.  It should be applied within two hours of irrigation or rainfall to be sure the chemical gets into the root zone, and it requires a 14-day pre- harvest interval.

Diseases:  As the fields come into bloom it is time to protect the flowers against infection by spores of the gray mold fungus, Botrytis cinerea. Fruit infections take place through the flowers, so gray mold control efforts must be focused on the bloom period.  Two to three sprays of fungicide are typically required to provide good protection. The first spray is usually applied at 5-10% bloom, followed by a second application at petal fall.  Additional applications may be applied if there is significant rainfall between or following these two sprays.

Leather rot (Phytopthora cactorum) may become a problem in fields where standing water is common during bloom and fruit development, especially if the fields were not mulched last fall. Incidence of leather rot can be reduced by applying straw mulch between the rows to prevent berries from touching the soil and reducing soil splashing onto the berries.  Foliar sprays of Aliette®, Agri-Phos® or Phostrol® may be applied during bloom and fruit development to prevent leather rot when there has been excess moisture in a field, especially those with a history of this problem.

Powdery mildew:  We have not yet seen symptoms of this fungus disease in fields.  It tends to be more prevalent under warm, humid conditions. It may first appear as purple or red blotches on the leaf and flower stems. Later, upward curling leaves and white, powdery growth on the undersides of the leaves becomes evident. Check your fields for pinkish purple leaf and flower stem lesions as new leaves emerge. Pristine®, Cabrio®, Topsin-M®, captan, Procure®, Torino® and JMS Stylet Oil® are registered to control powdery mildew.

Angular Leaf Spot

Bacterial Angular Leaf Spot, Photo by David Handley

Angular leaf spot is a bacterial disease characterized by small water-soaked spots on the leaves, which may turn yellow or black. The symptoms start on the lower leaves but spread throughout the foliage when spores are splashed up by rain or irrigation water. Infections can cause blackening of the berry stems and caps. This disease is favored by extended cool, wet weather with night temperatures close to freezing. Irrigating fields for frost protection encourages development and spread of the disease. Hydrogen dioxide (OxiDate®) may have some activity against angular leaf spot when used on strawberries as part of a gray mold management program.

Sincerely,

David T. Handley
Vegetable and 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.

Learn to Preserve the Harvest with UMaine Extension

May 20th, 2015 8:00 AM

Enjoy the taste of summer fruits and vegetables all throughout the year by taking the University of Maine Cooperative Extension’s Preserving the Harvest workshop 5:30–8:30 p.m. Tuesday, June 23 at UMaine Regional Learning Center, 75 Clearwater Drive, Falmouth.

The workshop, led by UMaine Extension staff members, includes hands-on, USDA-recommended food preservation methods. Participants will preserve low-sugar strawberry jam and learn basics of hot water bath canning and freezing to preserve pickles, jam and vegetables. Fresh produce, canning jars and other equipment will be provided. Participants should bring a pot holder.

Cost is $20 per person; partial scholarships are available. Register online by June 19. For more information, or to request a disability accommodation, call 781.6099, 800.287.1471 (toll-free in Maine).

Strawberry IPM Newsletter No. 1 – May 8, 2015

May 8th, 2015 2:42 PM

StrawberriesStrawberry IPM Newsletter No. 1 – May 8, 2015

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2015 STRAWBERRY PEST MANAGEMENT SEASON BEGINS

Long, Cold Winter Delays Early Spring Growth

Situation:
A long cold winter has suddenly departed and warm temperatures are now moving strawberry growth along very rapidly. Most fields had adequate snow cover to prevent serious winter injury, but we expect some fields may start showing symptoms as the plants start to flower. Cutting into the crowns of injured plants will reveal dark brown discoloration in the internal tissue. Helping plantings recover from winter injury involves compensating for the damaged vascular system. Make sure the plants get plenty of water, especially in this dry period; and it may help to apply extra nutrients to encourage root growth and recovery, including nitrogen, calcium, and phosphorus. While we do not recommend heavy nitrogen fertilizer applications in the spring, up to 20 pounds of actual N (e.g. 125 lb. calcium nitrate) may improve early spring growth. Warmer temperatures will also increase insect activity. We have heard early reports of both strawberry clipper and tarnished plant bug.

2015-2016 New England Small Fruit Management Guides are available at Highmoor Farm. The guide contains the latest information on management options for small fruit pests as well as cultural information. Cost of the guide is $13.00 plus $2.69 postage for a total of $15.69.

To order the guides, please send your check made payable to UMaine Cooperative Extension mailed to: Highmoor Farm, P.O. Box 179, Monmouth, Maine 04259, attention Pam St. Peter. For more information, contact Pam St. Peter at 933.2100 or pamela.stpeter@maine.edu.

Members of the Maine Vegetable and Small Fruit Growers Association (MVSFGA) or the New England Vegetable and Berry Growers Association receive free copies of the guide. For MVSFGA membership information, contact Bill Jordan at 799.1040.

We will begin scouting strawberry fields for major insect pests within the next two weeks, including volunteer farms in North Berwick, Wells, Cape Elizabeth, Poland Spring, New Gloucester, Dresden, Monmouth, Wayne, and Farmington, and will be reporting our findings through this newsletter and blog on a weekly basis until harvest time. You can also get quick access to this information on the Pest Management web page at http://umaine.edu/ipm/.

The best way to manage strawberry pests is to scout your own fields regularly and often. You should start scouting regularly as soon as flower buds emerge from the crown. You should be able to identify the major pests and their damage, and be able to determine if control measures are necessary. To properly scout your fields you may want a copy of the Strawberry Production Guide for the Northeast, Midwest and Eastern Canada. This contains detailed information on strawberry pest identification and monitoring, and also provides information on all other aspects of strawberry production. It may be purchased for $45.00 per copy from the University of Maine Cooperative Extension online.

Clipper Beetle on Strawberry Bud

Clipper Beetle on Strawberry Bud, photo by James Dill

Strawberry bud weevil or “clipper” will become active as flower buds begin to emerge. We have had reports of clipper activity within other New England states and in southern Maine. The clipper is a small weevil, which girdles strawberry flower buds, causing them to dry up and fall off the flower stalk. Scout for damage by counting the number of clipped buds in two feet of row length at five different locations in a field. If the average number of clipped buds per two-foot sample exceeds 1.2, or if live clippers are found, control measures are recommended. Damage is usually first noticed at the edges of the field. Border sprays may be effective in keeping this insect from becoming a problem in larger fields. Fields with a history of clipper problems will typically exceed threshold nearly every year. Insecticide options for clipper include Lorsban®, Brigade®, Sevin® and PyGanic®.

First Instar Tarnished Plant Bug Nymph

First Instar Tarnished Plant Bug Nymph, photo by David Handley

Tarnished plant bugs adults have been reported in southern Maine, indicating that they will soon be laying eggs. Strawberries are one of their preferred hosts at this time of year. Once the eggs start to hatch, we’ll find the nymphs feeding in the flowers. The nymphs are small, active, yellow-green insects. It is important to scout for them regularly, as they can appear very quickly in warm weather. Tarnished plant bugs feed on the open strawberry flowers, causing the berries to have seedy ends. To scout for the nymphs shake 30 flower clusters (six clusters in five different locations) over a plate. If four or more of the clusters out of the 30 sampled have any nymphs, control measures should be taken. Be on the alert and scout your fields now! Insecticide options for tarnished plant bug include malathion, Brigade®, Danitol®, and PyGanic®.

Cyclamen Mite Damage

Cyclamen Mite Damage, photo by David Handley

Cyclamen mites: Plants showing weak growth and yellow, pinkish or blackened, crinkled leaves may be infested with cyclamen mite. Cyclamen mites are very small, smaller than spider mites, and reside in the crown of the strawberry plant feeding on the developing leaves and flower buds. They are very hard to see, even with magnification. Infested plants have shrunken distorted leaves and flower stalks, and produce few, if any, marketable fruit. Miticides such as Kelthane® and Portal® can be effective, but must be applied in lots of water to be sure that the material is carried down into the crowns where these mites reside. Thionex® may also be used, but registration of this product on strawberries will run out in July of 2016.

Two-spotted Spider Mites

Two-spotted Spider Mites, photo by David Handley

Two-spotted spider mites have not yet been a problem this spring, but growers with plants under row covers should be alert. This is often where we first find mite problems. Spider mites will reproduce rapidly when warmer weather arrives, so it is important to scout for them regularly. Spider mites feed on the undersides of strawberry leaves, rasping the plant tissue and sucking the sap. Infested leaves will develop yellow flecking and a bronzed appearance. The plants become weakened and stunted. Fields that have had excessive nitrogen fertilizer and/or row covers tend to be most susceptible to mite injury. To scout for mites, collect 60 leaves from various locations in the field and examine the undersides for the presence of mites. Mites are very small – you may need a hand lens to see them. Chemical control options for two-spotted spider mites include Acramite®, Portal®, Nealta® Savey®, Zeal®, Vendex®, Oberon®, Brigade®, Danitol®, Thionex® and JMS Stylet Oil® (oils will cause plant injury if used in combination with captan or within 14 days of an application of sulfur).

Strawberry Root Weevil Grub

Strawberry Root Weevil Grub, photo by David Handley

Root weevil management
Fields that were infested with root weevils last summer should be inspected for grubs this spring. Infested plants appear week and stunted, usually in somewhat circular patches in a field. Digging under the plants will reveal small (1/4”-1/2”) crescent-shaped legless grubs. Typically, the grubs begin to pupate when the plants are in bloom. A soil drench of Platinum® (thiamethoxam) insecticide during the spring and/or fall when the grubs are active in the soil can provide control. However, Platinum® has a 50 day pre-harvest interval, so it is too late for applications in most fruiting fields this year. Platinum® may also be used as a pre-plant or planting treatment for root weevils. It is not too late to put on an application of nematodes to control the grubs (optimal timing is about mid-May). Two species of nematodes appear to offer the best control of root weevil grubs. Heterorhabditis bacteriophora (Hb) appears to be the best candidate for control of root weevils when the soil temperature is above 60 degrees, and is available from Green Methods, the Integrated Biocontrol Network, and Koppert Biological Systems.

Nematodes are living organisms and they can be killed if they are misapplied. Order nematodes ahead of time and be ready to apply them through a sprayer or irrigation soon after they arrive. Refrigerate them if you cannot apply right away. Do not apply nematodes using a sprayer with a piston pump. Use clean equipment, removing all screens finer than 50-mesh. Apply nematodes in early morning or evening in a high volume of water to already moist soil, pre-irrigating if needed. Apply another ¼ inch of irrigation after application to wash them onto and into the soil. Researchers and suppliers recommended 250 (if banded in the row) to 500 million per acre, at a cost of $100-$200 per acre depending on volume and source. Nematodes tend to work best in heavily infested fields. Strawberry plants can recover their vigor remarkably well if crown feeding has not occurred and diseases haven’t taken over the roots.

Once the adults become active in July, bifenthrin (Brigade®) will provide some control if used at the highest labeled rates. The best timing for this spray is at night during the peak feeding activity of adults, before they start laying eggs, or about the time harvest ends.

White Grub

White Grub, Photo by David Handley

White grubs: Weak growth noted in fields this spring may also be the result of white grubs feeding on the roots of newer plantings. These grubs are the larvae of beetles, including European chafer and Asiatic garden beetle. They differ from the larvae of black vine weevil and strawberry root weevil in that they have legs and a swollen anterior (rear end), and they tend to be larger. Their feeding weakens the plants by reducing the number of roots. The grubs can be found by pulling up weak plants and sifting through the soil that surrounded the roots. Controlling white grubs once they have become established in a field can be difficult. These tend to be more of a problem in new fields that have been planted following a grass rotation crop, because the adults prefer to lay their eggs in sod. Admire Pro® and Platinum® insecticides are labeled for control of white grubs and should be applied within two hours of irrigation or rainfall to be sure the chemical gets into the root zone. Admire Pro® requires a 14 day to harvest interval, while Platinum® requires a 50 day pre-harvest interval.

Gray Mold on Strawberries

Gray Mold on Strawberries, photo by James Dill

Diseases: Bloom is a critical time to protect strawberry fruit against gray mold caused by the fungus Botrytis cinerea, especially when conditions have been damp. Two to three sprays of fungicide during bloom are typically required to provide good protection against this disease. If you tank mix insecticides and fungicides, avoid spraying when bees are active. Botrytis cinerea overwinters on old leaves and plant debris. Fruit infections take place almost exclusively through the flowers, so gray mold control efforts must be focused on the bloom period. If the bloom period is dry and/or good fungicide coverage is maintained, incidence of gray mold at harvest should be low.

There are several excellent fungicide choices for control of gray mold in strawberries. Elevate® (fenhexamid) has good to excellent activity against Botrytis. Captevate® is a pre-mix of captan and fenhexamid and has a broader spectrum of activity than Elevate® alone. Switch® (cyprodinil and fludioxonil), Scala® (pyramethanil) and Pristine® (pyraclostrobin and boscalid) are also excellent products for gray mold control. Topsin M® + captan is also a good fungicide combination, but remember that captan is strictly a protectant and can be washed off by rain or irrigation water. Thiram is similarly effective but also susceptible to wash-off.

The fungicides Cabrio® (pyraclostrobin) and Abound® (azoxystrobin) are NOT suitable for gray mold control, but are effective against anthracnose and other fruit rot and leaf spot diseases. All fungicides mentioned above have a 0-day pre-harvest interval, except Topsin M® (1 day) and thiram (3 days). Remember to alternate fungicides with different modes of action for resistance management purposes.

Red Stele Symptoms on Strawberry Plant

Red Stele Symptoms on Strawberry Plant, photo by David Handley

Red stele root rot
Although early spring conditions have not been especially conducive to red stele development, you should still be alert for this root rot if any fields appear to be weak, stunted or dying. To diagnose red stele, pull up a few plants that look weak and scrape the roots of these plants to see if the center of the root, known as the stele, is rusty red in color, instead of the normal white. The red color would indicate an infection. Red stele is caused by Phytophthora fragariae, a soil pathogen that infects roots when soils are wet with temperatures around 50°F. The pathogen grows into the roots causing the plants to become weak, stunted and to eventually die. Symptoms are most evident in the spring, and can be mistaken for winter injury. Ridomil Gold®, Alliette® or Phostrol® are fungicides that can be applied in the late fall or early spring for control of red stele. Many varieties have some level of resistance to the disease, but the most effective management strategy is to plant only into well-drained soils, and/or plant onto raised beds.

Powdery Mildew

Powdery Mildew, photo by David Handley

Powdery mildew: This fungus disease may first show up as purple or red blotches on the leaf petioles and flower stems in strawberry fields. Most of us are more familiar with the later symptoms of upward curling of the leaves and white, powdery growth on the undersides of the leaves. Check your fields for pinkish purple leaf and flower stem lesions as new leaves emerge. Pristine®, Cabrio®, Topsin-M®, captan, Procure®, Torino® and JMS Stylet Oil® are presently registered to control powdery mildew.

Angular leaf spot is a bacterial disease that is characterized by translucent leaf spots that may turn yellow and eventually black. The symptoms tend to start on the lower leaves but may move upwards as bacterial spores are splashed up by rain or irrigation water. Infection of the calyxes may result in a blackening of the berry stems and caps, reducing their marketability. Bacterial angular leaf spot is favored by extended cool, wet weather and nights with temperatures close to freezing. Frequent irrigation for frost protection can greatly encourage the development and spread of the disease, as will extended cool, damp weather. Susceptibility to this disease appears to vary significantly between varieties. The copper-containing material Kocide®, can reduce the spread of this disease. Start spray applications before bloom to prevent multiplication of the bacteria on the leaves before they jump to the berry caps. Application of copper sprays after bloom can result in fruit injury and is not recommended. Hydrogen dioxide (OxiDate®) may also have some activity against angular leaf spot when used on strawberries as part of a gray mold management program.

Other Berries:

Raspberries are showing both significant winter injury and cane breakage from snow in many fields. I expect even more winter injury to become apparent once the floricanes start to flower. Tip dieback often occurs due to winter damage to the vascular tissue within the canes. Strawberry clipper will also attack raspberry blossoms, so keep an eye out for this insect once flower buds emerge.

Highbush blueberries are also showing significant winter injury in some fields. Dark brown or black discoloration of last year’s shoot growth, and/or shriveling of the shoot tissue indicate winter injury and desiccation, frequently resulting in death of the flower buds. Cane breakage from heavy snow loads is also common in fields. Mummy berry spores are starting to be active in southern and coastal Maine. Expect infection periods to occur over the next few weeks, anytime there is a significant moisture event (rain, mist, fog). Protectant fungicides for mummy berry include Indar®, Orbit®, and Quilt Excel®.

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.

 

High Tunnel Workshop – May 16, 2015

April 10th, 2015 12:55 PM
High Tunnel Tomatoes

High Tunnel Tomatoes, photo by Danielle Murray

High Tunnel Workshop

THIS WORKSHOP HAS BEEN CANCELLED DUE TO LOW ENROLLMENT.

Saturday, May 16, 2015
8:00 AM to 3:00 PM
Cost: $30.00
Location:
Morning session 8:00 AM to 12:45 PM

Maine Sea Coast Mission’s Chapel (Weald Bethel Center), 39 Weald Bethel Lane, Cherryfield, ME 04622
Afternoon session 1:00 PM to 3:00 PM
Salty Dog Farm, 269 Back Bay Road, Milbridge, ME 04658

Preregistration is strongly encouraged. Please preregister by May 12, 2015.

Register online or contact Mark Hutton at mark.hutton@maine.edu or 207.933-2100 to preregister.

This workshop is designed to help people who are interested in using high tunnels for vegetable and fruit production as part of a commercial enterprise. Interest in growing crops in high tunnels is expanding as demand for locally grown produce expands and people seek to extend their growing season. Types of tunnels, construction, irrigation, fertility and crop requirements will be discussed with University of Maine Cooperative Extension’s Dr. Mark Hutton, Vegetable Specialist. Sam Cheeney and Sasha Alsop, who run a full-time vegetable market garden on Salty Dog Farm in Milbridge will host the afternoon session.

The morning session of the workshop will be held at the Maine Sea Coast Mission’s chapel, the Weald Bethel Center, in Cherryfield (telephone 207.546.4466 and website http://www.seacoastmission.org/downeast_campus.html). The afternoon session will be held at the Salty Dog Farm in Milbridge (telephone 207.546.2676).

For more information about this workshop, contact Regina Grabrovac at 207.255.3741 or regina@healthyacadia.org.

AGENDA

8:00 AM Registration at the Maine Sea Coast Mission’s chapel in Cherryfield

8:15 AM High Tunnel Site Location and Preparation, Structures, Building Tips

9:00 AM Soil and Fertility Management, Irrigation Practices

10:00 AM Break

10:15 AM Basics of High Tunnel Vegetable and Flower Production

11:45 AM Bag Lunch at the Chapel

12:45 PM Travel to Salty Dog Farm

1:00 PM Salty Dog Farm in Milbridge: On-site Discussion of Grower Practices and Tools

Any person with a disability who needs accommodations to participate in this program should contact Mark Hutton at mark.hutton@maine.edu or 207.933.2100 to discuss any needed arrangements at least seven days in advance.

Learn to Prune, Graft Apple Trees at Free Field Day

April 9th, 2015 1:26 PM

University of Maine Cooperative Extension is offering a free apple tree pruning and grafting field day from 10 a.m. to 1 p.m. Saturday, April 25, at Avalon Acres Orchard & Farm, 234 Dexter Road, Saint Albans.

Avalon Acres owner Mark Sheriff, an alumnus of the UMaine Extension Master Gardener Volunteers program, will present information about general planting and management practices for apple trees, and demonstrate pruning and grafting in the orchard. Home orchardists and those planning to plant apple trees this spring are invited to attend.

Pre-registration is requested but not required. Attendees should wear footwear appropriate for walking on uneven terrain. For more information, to register, or to request a disability accommodation, contact Pete Bastien, 207.474.9622, 800.287.1945 (toll-free in Maine).

UMaine Extension’s Free Garden Newsletter Available

March 6th, 2015 12:16 PM

Home gardeners can subscribe to the free March edition of the University of Maine Cooperative Extension’s 2015 Maine Home Garden News online. The newsletter, released monthly from March through October, is designed to equip beginning and experienced home gardeners with research-based information. Each issue includes a reminder list of timely actions in the garden and yard; articles on fruits, vegetables, flowers, lawn care, trees and shrubs; videos; and other informative resources. For more information, contact Lois Elwell, lois.elwell@maine.edu; 800.287.1471 (in Maine).

Spreading Good Cheer

March 5th, 2015 2:42 PM

For Nancy Bunting, farming hasn’t always been a bowl of cherries.

But it has included harvesting thousands of pounds of the sour fruit for Allagash Brewing Company to use in its beer.

In honor of Bunting, the Portland brewer named its October 2014 limited edition copper-colored beer “Nancy.”

The sour red ale tastes like a medley of tart cherry, citrus and pie spice, according to Jeff Perkins, brewmaster at Allagash Brewing Company. Its aroma is described as a blend of cherries, bread crust and cinnamon.

Bunting says she’s blessed to work with Allagash and to be the namesake of a niche brew.

For more than two decades, Bunting and her husband Earl have experienced both blessings and challenges associated with farming.

They own Doles Orchard, situated atop a ridge in Limington where guests pick their own fruit — including cherries, raspberries, peaches, plums, pears, strawberries, elderberries, blueberries and 25 varieties of apples — as well as go on hayrides and enjoy homemade pies and preserves.

During off-seasons, Earl has worked in carpentry and Nancy has waitressed.

The Buntings’ relationship with Allagash began in 2010, when brewers at the Portland, Maine-based company inquired about purchasing their sour cherries to use making Coolship Cerise, a traditional, Belgian-inspired spontaneously fermented beer.

Since that time, the Buntings have supplied Rob Tod’s company with more than 6,000 pounds of cherries that they picked, packed and delivered in wooden apple boxes that they built.

Allagash brewers continued using the tart fruit in the Coolship Cerise releases. And they were so impressed with the quality of the cherries, they decided to build a beer around them.

“Their fruit inspired us to brew ‘Nancy,’” says Perkins. “Over the years, we’ve been honored to develop a relationship with Earl and Nancy and we have been so inspired by their approach to farming. Because the cherries were from them, it was appropriate to make reference to their farm.”

Bunting laughs recalling that Allagash initially proposed naming the distinctive brew after her husband.

“Then they found out there already was a beer named Earl,” she says light-heartedly. “I’m second fiddle to Earl.”

Allagash employees also were impressed with the rustic boxes in which the Buntings delivered the cherries and asked if they could manufacture crates to hold 24 bottles of beer. The couple has since sold nearly 6,000 of the stylish, practical containers to the company.

“Selling beer in wood crates is traditional in Belgium,” says Perkins. “We wanted to do something like that for our own beers sold at the brewery.”

Nancy says she enjoys the independence of being a farmer and developing niche markets — including homemade crates and boxes and slate coasters.

While building boxes two years ago, Nancy severed four fingers in a table saw accident. Emergency room care, surgery and follow-up visits took a financial toll, as the Buntings didn’t have health insurance. But they worked out a payment plan and Nancy devised ways to adapt and continue to work on the farm.

“I’m still amazed at how much I can accomplish relatively hassle-free,” she says, adding she has been humbled by the generosity and goodwill of family and friends.

She’s also been humbled by Allagash Brewing — which routinely gives back to the community by donating some of its profits to local organizations.

When Allagash officials asked her which group she’d like a portion of Nancy’s proceeds to be donated to, Bunting did some online research. Her daughter in California told her about AgrAbility — the nationwide U.S. Department of Agriculture-funded program established to assist farmers, ranchers and other agricultural workers and farm family members impacted by a limiting health condition.

The Maine AgrAbility program is a nonprofit collaboration between University of Maine Cooperative Extension, Goodwill Industries of Northern New England and Alpha One. It assists farmers, fishermen and forest workers with challenges or limitations so they may continue to be productive and work safely — all of which Nancy could readily identify with.

And the Buntings already had a solid connection with UMaine Extension. For years, Nancy and her husband have sought expert advice from UMaine Extension educators about farming topics — from garden pests to egg production.

So Nancy asked Allagash officials to spread their generosity and good cheer to Maine AgrAbility.

Maine AgrAbility program coordinator Lani Carlson says since the project formed in 2010, it has provided technical information to 247 farmers and conducted on-site assessments and recommendations for 75 others whose agricultural businesses include dairies, Christmas tree farms, vegetable stands and hay sales.

Maine AgrAbility clientele, says Carlson, has included area farmers with chronic health impairments, post-traumatic stress disorder and traumatic brain injury, as well as with aging-related issues, including arthritis and hearing loss.

To educate people about the program is a huge thing,” Nancy says. “I’m happy to be getting the word out about this great program and all the ways it can help people.”

To date, Allagash Brewing Company has gifted nearly $10,000 to the organization.

“We are greatly honored to receive this gift,” says Richard Brzozowski, director of the Maine AgrAbility program. “The money will help us in our mission to assist Maine farmers and growers who have chronic health issues or injuries to gain more control over their lives and to continue to farm successfully.”

Talk about a cherry on top.

Contact: Beth Staples, 207.581.3777

Fruit Tree Class at Highmoor Farm – April 11, 2015

February 20th, 2015 10:21 AM

Fruit Tree Class

pruning a fruit treeSaturday, April 11, 2015
10:00 AM to 12:00 PM
Highmoor Farm, UMaine Agricultural Experiment Station
52 US Route 202, Monmouth, Maine 04259

Registration cost is $10.00. Please call 207.933.2100 to register, since class size is limited.

The Fruit Tree Class will cover basic pruning techniques, variety selection, pests and diseases, and cross pollination. The class will be taught by Renae Moran, Tree Fruit Specialist for the University of Maine. If weather permits, the class will be taught outdoors in the orchard. Students should meet in the parking lot behind the barn.

Please contact Renae Moran for more information about the class at 207.933.2100 or rmoran@maine.edu.

Visit the Highmoor Farm website for directions.

 

UMaine Extension Taking Orders for Asparagus, Rhubarb, Berry Plants

January 30th, 2015 10:49 AM

University of Maine Cooperative Extension is taking orders for its “Grow It Right!” plant sale, which is a fundraiser for the Master Gardener Volunteers program.

Available plants are a highbush blueberry three-pack, two varieties per pack, $35.95; 10-pack of asparagus crowns, $15; 25 young dormant strawberry plants, $15; five raspberry canes, $18; three blackberry canes, $25; and rhubarb crowns, $12 each. All are suitable for Maine’s climate and will be ready for spring planting.

Graduates of the UMaine Extension Master Gardener Volunteers program have been active for more than 30 years, doing demonstrations, creating community gardens, organizing educational events, growing food for Maine Harvest for Hunger and leading community-based volunteer efforts. Sale proceeds will support these projects and provide need-based program scholarships.

Orders must be placed by May 1. Plants will be available for pickup at Extension county offices Saturday, May 16 or Monday, May 18, depending on location. Purchase plants and get more information, including video clips on site selection and soil testing online.

To place a mail order, call Andrea Herr, 207.781.6099. For more information, or to request a disability accommodation, contact Richard Brzozowski, 207.781.6099, 800.287.1471 (in Maine), richard.brzozowski@maine.edu; or Marjorie Peronto, 207.667.8212, 800.287.1479 (in Maine), marjorie.peronto@maine.edu.