Jim Wargo from Valent U.S.A. passed these recommendations on for growers considering using Promalin on frost-affected trees. These make horticultural sense to me, and Jim highlights the limitations well. -TB

Promalin: What to do when freeze events occur at tight cluster to pink

Apples at tight cluster to early pink are more tolerant to cold temperatures than fully open flowers. Nonetheless, if the temperatures do get cold enough (27/28F), injury to flower reproductive parts can occur. I often get asked this time of year “will Promalin help set fruit after a damaging frost event at tight cluster to pink”. The short answer is yes, but there is a caveat. Don’t run out the next day and spray Promalin as if the trees were in full bloom. Be patient and follow the series of steps below.

Guidance on Promalin use when damaging frost occurs before the bloom stage:

• Do not apply Promalin the next day after a frost event during tight cluster and early pink growth stages: You will be underwhelmed by the results if you do. If trees are at full pink (all five unfurled flowers fully extended) then wait until the first few king flowers open

• Assess flower buds for cold injury at tight cluster to pink: Do this by dissecting flowers that have not yet fully opened to see if the reproductive flower parts are still alive. If you see brown discoloration inside the developing flower, then it means the female part of the flower (pistol) is dead and no pollination or fertilization will occur. The tree will subsequently shed those flowers. Note: In many cases the flowers will open and look fine (no injury to the petals), but that can be deceiving. Make sure to inspect the flower reproductive parts closely as previously mentioned.

• Determine the injury threshold: It’s up to you to determine if there are enough damaged flowers on the trees that may result in reduced fruit set and crop loss. Remember, you don’t need every flower to set. In most cases, the goal is for only one of the five flowers on a spur to develop in to a fruit. It’s also important to have an adequate number of non-fruiting spurs for next year’s crop. Don’t panic if there is modest flower injury. Consider it your first thinning application…

• Decide: If your damage assessment suggests that crop loss is likely then you can make the choice to spay Promalin on the trees to increase fruit set. Apply one pint of Promalin/Acre, timing the application to first flower/early bloom stage . Applications made later than early flowering have been shown to be ineffective in situations where flower injury occurred from freeze events at tight cluster through pink. Use sufficient water volume ~100 gal/Acre to ensure good coverage and apply under slow drying conditions if at all possible.

It’s important to understand how Promalin works and what its limitations are. While I will not go in to all the details in this article, I want to underscore a few key points

1. Promalin IS NOT an anti-freeze type product. It will not lower the freezing point of the plant tissue if applied ahead of a frost event

2. Promalin WILL NOT revive, resuscitate or repair plant/flower tissue that is damaged by freezing temperatures

3. Promalin is basically equivalent to hormone replacement therapy in humans. In the normal pollination process, fertilized ovules begin to develop in to seeds that produce hormones including cytokinins and gibberellins. These hormonal signals tell the tree there is viable seed in the apple. The seed is essentially the offspring, and the tree will continue to nourish the developing seed with carbohydrates and nutrients. However, if fertilization does not happen due to reproductive flower injury or poor pollination weather, then no viable seed will develop. In that scenario, the tree is much more likely to shed the fruit and put it’s energy in to those apples that have the potential to produce progeny. That’s where Promalin comes in. Promalin applied to sterile flowers provides the hormonal signal that would normally come from the developing seed. That’s why it’s important to synchronize the application of Promalin with the trees natural phenology – slightly ahead of or during the early pollination window. Trees don’t receive hormonal signals from developing seeds from tight cluster through pink, so why apply Promalin then? The cytokinin and gibberellins will be long gone by the time bloom comes around. Coincide the application to the same stage the tree is expecting to receive those signals instead. The fruit that develops after Promalin application will have low seed count or no seeds at all, but it will develop to normal size as research studies have shown.

Note on Pears:

There was some confusion abut Promalin being labeled for fruit set on pears. The issue is that both CDMS and Agrian had outdated labels that did not include this use pattern. The Promalin label was updated a few years ago and now allows use on pears for fruit set. It can be used on pears to set fruit in the absence of frost. See below for guidance.

Good afternoon:

I was a bit surprised to see how cold it got this morning, despite not having any frost on my windshield at 6:00 am. We recorded 25.7 degrees Fahrenheit in South Burlington, 21.6 in East Montpelier, 27.3 in Cornwall, 26.3 in Putney, as general examples. Definitely colder that the 30 or so that I was expecting. Fruit buds at the UVM orchard in South Burlington are generally at the tight cluster stage, and the general consensus is that buds at that stage see damage at 27 degrees and may have full crop loss at 21 degrees. I pinched some buds and saw some damage that I outline in this video, for those of you who want to keep an eye on things yourselves:

Some browning in some fruit buds may be expected, depending on where you are at and how cold it got. But it’s still early- buds may recover from slight freezing, and there is a good bit of time to go before bloom. For those who are concerned, please know that I generally won’t recommend any miracles you can put in a spray tank. There are a lot of materials out there that purport to save fruit from frost but a lack of good research on many of them. That said, this is a great time to apply Dr. Warren Stiles’ ‘cold weather prebloom cocktail’ of nitrogen (urea (3 lb./100 gallons dilute, or one of the liquid formulations like N-Pact at label rate), zinc (use label rate of your favorite product) and boron (0.1 -0.3 lb. B/acre) that will help top strengthen fruit buds going into bloom.

As I said before, keep fungicides on ahead of expected rains. The weather the past few days may or may not have led to an apple scab infection period, but we may be facing a pretty substantial one early next week.

—

Where trade names or commercial products are used for identification, no discrimination is intended and no endorsement is implied. Always read the label before using any pesticide. The label is the legal document for the product use. Disregard any information in this message if it is in conflict with the label.

The UVM Tree Fruit and Viticulture Program is supported by the University of Vermont Agriculture Experiment Station,  UVM Extension, USDA NIFA E-IPM Program, and USDA Risk Management Agency.

UVM Extension helps individuals and communities put research-based knowledge to work. University of Vermont Extension, and U.S. Department of Agriculture, cooperating, offer education and employment to everyone without regard to race, color, national origin, gender, religion, age, disability, political beliefs, sexual orientation, and marital or familial status.

I don’t have a lot more to say than I said last time- if you’re expecting rain, expect to protect your orchard from apple scab. We are entering the accelerated phase of primary apple scab season now, and given how wet it was last year I expect there is a fair amount of inoculum out there so that even small releases of spores (as a percent of total potential infection) could cause substantial disease. This week I made a quick video where I walk through my thinking regarding whether or not we need a fungicide in the UVM orchard using NEWA, how to predict spray windows using other online tools, and how to select the materials we will be applying using the New England Tree Fruit Management Guide.

https://www.youtube.com/watch?v=8_sbm7yad-4

Where trade names or commercial products are used for identification, no discrimination is intended and no endorsement is implied. Always read the label before using any pesticide. The label is the legal document for the product use. Disregard any information in this message if it is in conflict with the label.

The UVM Tree Fruit and Viticulture Program is supported by the University of Vermont Agriculture Experiment Station, UVM Extension, USDA NIFA E-IPM Program, and USDA Risk Management Agency.

UVM Extension helps individuals and communities put research-based knowledge to work. University of Vermont Extension, and U.S. Department of Agriculture, cooperating, offer education and employment to everyone without regard to race, color, national origin, gender, religion, age, disability, political beliefs, sexual orientation, and marital or familial status.

SPRING ORCHARD PEST AND POLLINATOR SHOWCASE

Offered at two locations:

Sweetland Farm

97 Kerwin Hill Road, Norwich, VT 05055

Thursday May 9, 2024 from 4:30-7:00pm

UVM Horticulture Research and Education Center (HREC) and Catamount Educational Farm

65 Green Mountain Drive, South Burlington, VT 05403

Friday May 10, 2024 from 4:30 to 7:00pm

Join the Vermont Tree Fruit Growers Association and the University of Vermont Extension at these free hands-on field meetings to increase your identification skills and understanding of common orchard pests, wild pollinators, insect habitat, and pollination in tree fruit production. These events are FREE and geared to commercial growers and people that work with them. Pesticide applicator credits available: 2 credits for categories 1A, 10, 1, 2, 3, 4, 5, and 6. Certified Crop Adviser CEUs available: 2 Integrated Pest Management credits.

Registration is not required, but helpful for any unexpected announcements regarding the meetings. Let us know if you plan to attend by contacting Laura Johnson at laura.o.johnson or 802-656-4827.

To ask questions about these events or to request a disability-related accommodation to participate in these programs, please call or email Laura Johnson as soon as possible before the event you wish to attend so we may assist you.

Tree Fruit Twilight Meeting and agenda.pdf

Good morning:

The NEWA system that most of us rely on for pest models and forecasting is not importing data from any stations right now because the data centers at the National Weather Service that process the data are experiencing outages. Until it is back up, we’ll need to rely on some rules of thumb to manage apple scab, which is the only real IPM issue of immediate concern right now. We can assume that all orchards except maybe those in the coolest inland/upland sites are in the accelerated scab phase. That means keeping covered with a protectant fungicide (mancozeb for most, sulfur for those managing organically) before every rain, and adding a material with postinfection activity if you think that coverage was questionable going into a wetting event. As they work better in cooler weather and have little activity against fruit scab so are of less use postbloom, Vangard or Scala (FRAC class 9 Anilinopyrimidine fungicides) are good choices.

I just posted a video yesterday on hanging tarnished bug traps to start the monitoring season. For most orchards that sell fruit direct to consumers I don’t worry too much about this pest, but they can cause substantial damage to wholesale-marketed fruit and to peaches. The trap is the same as that used for European apple sawfly, which we’ll hang in a couple of weeks and can be more damaging. Many here know that I am generally not a fan of prebloom insecticides for most Vermont orchards, but they can be an important tool in some situations. I’ll be including regular monitoring updates this season to help you to implement scouting on your farm.

On a similar note, a grower sent me pictures of aphids in their apple buds the other day. It is a bit early to see them, but I advised to wait and watch before taking action. Strating off with insecticide treatments this early in the season is a sure way to throw orchard ecology out of balance and favor secondary pests like mites and aphids that would be controlled by predator insects and allow them to become season-long pests.

More to come, and please keep and eye on https://newa.cornell.edu/, as I am sure it will be back in operation soon.

-TB

__

Terence Bradshaw (he/him)
Associate Professor, Specialty Crops
Interim Chair
Department of Plant and Soil Science
College of Agriculture and Life Sciences

University of Vermont
117/210 – Jeffords Hall | 63 Carrigan Dr
Burlington, VT 05405

(802) 922-2591 | tbradsha
https://go.uvm.edu/pssbradshaw

Information for commercial orchard and vineyard managers in Vermont and beyond:

UVM Fruit Website | UVM Fruit Blog
Horticulture Research and Education Center
Message me on Teams

UVM’s Our Common Ground Values:
Respect | Integrity | Innovation | Openness | Justice | Responsibility

UVM is subject to the Vermont Public Records Act and communications to and from this email address, including attachments, are subject to disclosure unless exempted under the Act or otherwise applicable law.

Wine Sensory Evaluation Workshop

April 25, 2024, 9:00am – 12:00pm

Miliea Estate Vineyard, 450 Hollow Rd, Staatsburg, NY 12580

Attendance Fee : $20.00/person

In collaboration with Jeremy Schuster, Viticulture Specialist at the ENYCHP, Dr. Anna Katharine Mansfield and Chris Gerling, Enology Extension Specialists with the Cornell Craft Beverage Institute, will be presenting a wine production-focused, interactive workshop on sensory evaluation.

Topics include:

1) Are you a "super taster"? What does that mean?

2 Sensory thresholds, anosmias, and their critical role in wine evaluation

3) Flaws, faults, and taints, oh my! Sorbate flaws, oxidation, volatile acidity, TCA, Brettanomyces, & agricultural taints will be discussed

4) The perils of sensory descriptors

To register:

https://enych.cce.cornell.edu/event.php?id=1918

Laura McDermott┃Pronouns: she, her, hers

Sr. Extension Associate, Eastern NY – 415 Lower Main Street, Hudson Falls, NY 12839

Cornell Cooperative Extension|Eastern NY Commercial Horticulture Program

Website┃Facebook┃Instagram┃Blog┃Podcast

Phone: 518-746-2562

Mobile: 518-791-5038

Cornell Cooperative Extension is an equal opportunity, affirmative action educator and employer

Passing this in from the Agency of Agriculture. -TB

Hello,

The Agency of Agriculture is excited to announce that the Resilient Food System Infrastructure (RFSI) grant details will be released very soon! We’re reaching out to partners, TA providers, and those who supported our stakeholder engagement to offer a “heads up” that the RFA will be released next week; we know there may be an influx of questions once that goes live and we’ve gotten feedback that even a small bit of advance notice is helpful.

Some basics of the grant and the two tracks:

· Grant Overview: One-time USDA funding to build resiliency in the middle of the supply chain (aggregation, distribution, manufacturing, processing, storing, transporting, and wholesaling). Grants will support market development for local and regional food products, promoting value-added products, and fair and safe jobs.

· Track 1 – Infrastructure: Grant details will be announced in mid April, with applications open early Mary to early June 2024. Approximately $2 million will be available in grants ranging from $100,000 – $500,000 with a match requirement (reduced match available). Projects will begin in late fall 2024.

· Track 2 – Equipment-only: Grant details will be announced in August 2024, with applications open in the early fall. Approximately $1 million will be available in grants ranging from $30,000 to $100,000 with no match requirement. Projects will begin in early 2025.

• Applicants can only be awarded one RFSI track; applicants for the infrastructure grant will know if they are being recommended for award to USDA before the Equipment-Only Track opens in August.

· Eligible projects: supporting the middle of the supply chain by expanding processing capacity, modernizing equipment or facilities, construction, packaging capacity, storage space, updated or climate-smart equipment, etc. This funding cannot support meat, poultry, seafood, animal feed, fiber, cannabis, farm production, or retail. On-farm processing or value-add is eligible.

· Eligible applicants: farmers, processors, nonprofits, local government, institutions, food hubs, distributors.

· Priority will be given to projects who benefit limited resource farmers and ranchers, new and beginning farmers and ranchers, and veteran farmers.

We will hold a recorded webinar on April 30, 2024 from 11am – 12pm where applicants can hear more details and ask questions. Register here.

We will also continuously update a FAQ document, as we know this funding is a bit complex. If you have any questions, please send my way, and I can either respond now or include in the FAQ.

Please feel free to spread the word and we look forward to getting all the details online in 2 weeks!

Thank you,

-Julia

Julia Scheier (she/her)

Market Development Section Chief | Vermont Agency of Agriculture, Food & Markets

116 State Street, Montpelier, Vermont 05602-2901 | http://agriculture.vermont.gov

Tel: 802-522-7042

At this time of the year, we should always be keeping an eye on the weather in the week ahead, and the shift toward warmer temperatures this week means that we may be seeing the first signs of green tissue on trees in many sites in Vermont. Green tip indicates the beginning of the growing season, and is an important biofix for apple scab models. Keep checking your trees daily and note the date when 50% of buds on ‘McIntosh’ have opened enough to see green tissue from the side. That date should be used in NEWA to mark your biofix for apple scab ascospore maturity. For the UVM Horticulture Farm in South Burlington, that was today.

Potential for apple scab infection increases with temperatures as more ascospores mature to be released in rain events. In the early season. Not many spores are mature, and if you had good scab control last year, i.e., no visible lesions all season, then the small percentage of mature spores in a low inoculum situation may give you some early season breathing room. But if you did have a problem with scab last year, or a neighboring orchard harbors substantial inoculum, you should be ready early in the season to protect your trees. Copper is the standard, first spray of the year in virtually all orchard, as it helps to reduce fire blight inoculum and is a moderate fungicide against scab that can cover the first infection event for that disease.

But copper is a tricky material- it must be on the plant and not washed-off by the time fire blight cankers are oozing with the onset of warm weather, but if applied too late, copper ions on developing buds can cause fruit russeting. I would plan on applying copper to any orchard that had any amount of fire blight last year and which is showing green tissue or at least solid silver tip as soon as you have a suitable spray window. If possible, I would plan on applying copper to any orchard, period, that is between silver tip and half-inch green in the next 7-10 days. There is a pile of materials out there and for all intents and purposes for this delayed dormant spray any of them are effective as long as you are applying a good full rate of copper ions. The standard dry materials like Champ, C-O-C-S, Cuprofix, Kocide, etc. will give you the best bang for the buck here, and I would apply the full label rate for any of them and thoroughly spray the whole orchard. The only caveat I offer is if phenology advances rapidly before you can get out there and the trees are at 1/2” green tip, in that case, I would apply a low to middle rate. After 1/2” green tip, unless you don’t care about fruit finish (e.g., cider fruit), I would avoid copper.

This isn’t a bad time to get oil on, either, but the rate should be 2% by volume and coverage absolutely thorough to soak overwintering mite eggs, scale, and aphids. If time is of the essence, focus on copper first.

There is still time to do some sanitation in the orchard by flail mowing leaves and fine brush, and/or applying a coarse urea spray (44 lb feed grade urea in 100 gal water applied per acre, directed at the leaf litter) to speed decomposition and reduce apple scab inoculum.

Keep an eye on NEWA regularly as we enter into the 2024 season. I am seeing some stations that are offline- please contact me if you need help maintaining yours. Up-to-date spray tables may be found in the New England Tree Fruit Management Guide available online at netreefruit.org and shortly in hard copy format.

__

Terence Bradshaw (he/him)
Associate Professor, Specialty Crops
Interim Chair
Department of Plant and Soil Science
College of Agriculture and Life Sciences

University of Vermont
117/210 – Jeffords Hall | 63 Carrigan Dr
Burlington, VT 05405

(802) 922-2591 | tbradsha
https://go.uvm.edu/pssbradshaw

Information for commercial orchard and vineyard managers in Vermont and beyond:

UVM Fruit Website | UVM Fruit Blog
Horticulture Research and Education Center
Message me on Teams

UVM’s Our Common Ground Values:
Respect | Integrity | Innovation | Openness | Justice | Responsibility

UVM is subject to the Vermont Public Records Act and communications to and from this email address, including attachments, are subject to disclosure unless exempted under the Act or otherwise applicable law.