VT Apple IPM

Word is getting out in the media about the crop loss from the May 18 freeze. I am trying to manage the messaging a bit to nudge writers to encourage customers to support orchards and other farms this year. We don’t need the public writing the crop off before we even have. On that note, I am hearing a few promising signs that there are some fruit out there, even in some orchards that thought they had zero to work with. Some inland orchards are reporting 10-30% of a crop where we thought there was none. That’s a good thing, even if frost-disfigured fruit only make it into cider. But that also complicates management.

I’m considering apple scab still active in most parts of the state, even if NEWA says otherwise. Extended dry weather pauses ascospore maturity and makes the models less predictable. Next week looks showery and most orchards should see any final spores release in the next significant wetting event. Keeping fungicide protection on now will prevent scab from building and will also reduce the likelihood of other diseases like Botryosphaeria leaf spots and rots and apple blotch or Marssonina building up and causing tree defoliation and other symptoms. These relatively weak fungal diseases are often managed when spraying for scab and summer fruit diseases, so maintaining at least a minimal spray program will help prevent them from becoming established in the orchard to become a problem next season.

Insects still need management. Check NEWA or your min-max thermometer and calculate your degree days to run your models for the important pests now- plum curculio, codling moth, and the leafrollers. PC is nearly done with its egglaying period in most orchards. Codling moth is just about to hatch so next week looks like a good time to manage that pest with targeted treatments. Look to the New England Tree Fruit Management Guide for best materials to consider.

VT Grape IPM- Vintage 2023 is picking up steam

By now vineyards should have shown the effects of the May 18 freeze event (and a little damage here and there from the less severe May 26 frost that some sites may have seen) and it appears that, by and large, all is not lost. That isn’t to say that there isn’t extensive, and sometimes massive damage in many vineyards. In some cases secondary or even tertiary shoots are pushing, in some cases we don’t’ even have that. But it does sound like there will be wine from much of the state. Here are some management considerations to think about moving ahead.

First, keep up on your disease management. We are entering the immediate prebloom period where all of the major early season diseases are active. It’s (finally) been wet but not a soaking rain for the past week and next week looks showery. Keep your fungicide coverage on, even if you don’t think you’ll have a crop. Obviously no shoots means no tissues to protect, but even fruitless shoots will be susceptible to disease and unmanaged disease this year will become a big headache next year as you’ll have a large overwintering inoculum.

Next, keep an eye on water. I know most grapes in Vermont are not irrigated but in a year like this. At the UVM Horticulture Center we have received just over an inch of rain in the past month. That’s not enough for sufficient growth and production.

Finally, you should now be looking at any canopy management that the vineyard needs. In areas with little freeze damage, this is the time to thin shoots down to 4-6 per foot of canopy. That foot can be on a cane, cordon, or other structure. The cordons or canes may have been compromised and not pushing any shoots, you may be seeing growth coming from the head at the top of the vine trunk. If that zone, which we may say is about one foot, is all you have that is pushing buds, then I would leave more than the 4-6 that the above formula would call for, but rather leave double that. You will need to be tying and training canes in the next few weeks to manage that growth and reduce shading and moisture buildup. If you decide that the vine needs to be rebuilt from the ground up, keep an eye out for shoots that emerge from the root zone (non-grafted vines only) to train up as new trunks. I know the tissues low to the ground are among the most vulnerable in a frost, but the root system may be a source of new shoots produced from hidden or adventitious buds.

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.

Meeting for Local Orchardists (Putney, VT, June 14)

Sorry I won’t be able to make this but anyone from the fruit industry who wants to share your experiences relating to the May 18 freeze is welcome to join. And if you haven’t contacted FSA yet, be sure to do so. -TB

FOR IMMEDIATE RELEASE

Local orchardists and other growers are invited to a meeting on June 14 at 7:30 pm at Green Mt Orchards , West Hill Rd, Putney, Vt. with State Sen. Wendy Harrison and State Rep. Mike Mrowicki along with UVM Agriculure Extension Agent Vern Grubinger.

The meeting is for local food producers to share about their losses from the severe freeze that occurred in May. Estimates are that almost all of the local apple and peach crops have been wiped out for this year. Other growers have also experienced losses and your local legislators want tom assess the damage and try and find ways to help.

The meeting is open to the public. Any grower who has experienced a loss is encouraged to attend or to contact by email; Sen. Harrison wharrison or Rep. Mrowicki mmrowicki

Mike Mrowicki

Vermont State Representative
Windham4 District- Putney& Dummerston
mmrowicki

Important: Crop Damage Reporting to FSA Offices

Good morning:

I spoke with USDA Farm Service Agency officials last week and they are receiving relatively few reports of the crop damage from the May 18 freeze event. We are anticipating some form of federal assistance to come, which will likely be administered through FSA offices.

Please contact your FSA office (details attached) as soon as possible to indicate potential crop loss on your farm. You do not need to file a detailed report, just to get on the list.

Thanks,

Terry

FSA Service Center Directory.pdf

VT Apple IPM

It’s finally looking like there’s a better than zero chance for rain in the next few days. Everyone, regardless of the status of your apple crop, should be covered going into this (hopeful) rain event. If you have fruit, plum curculio is likely your main pest of concern right now, we’re about a week away from codling moth egg hatch. Keep an eye on your fruit set and if fruit are still clustered up, consider a thinner.

Be careful (or just don’t) with spraying in heat. I’ve done a good bit of damage to fruit and foliage when spraying over 85°. Best window if you can cover the orchard quickly enough is once it starts cooling down tonight through tomorrow. The front coming through will bring wind.

That’s all for now- I have a sprayer to set up.

-Terry

VT Apple IPM: Management in light of a difficult crop situation

We have been collecting damage data from orchards across the state this week, and the news is generally not good. It does seem like we have three classes of damage: near-complete crop loss inland and Connecticut Valley, some degree of often substantial loss in the Champlain Valley, and a good crop in the Champlain Islands and near the lake. As far as management goes, that leaves us in three different scenarios, and those in one of the scenarios- complete crop loss- may not be crazy about hearing me discuss how the lucky ones tend to their crop this season. I’ll make some notes in a bulleted list without much formatting, as I have more orchards to scout this afternoon:

  • Apple scab- This one is easy, it is still active, with no orchards having discharged all overwintering inoculum yet. Wetting events are few and far between but all orchards need to keep covered against scab. Be sure to include a fungicide effective against rust, like a DMI (FRAC code 3) or SDHI (FRAC 7) and/or powdery mildew (strobilurin, FRAC 11) in a couple of sprays to keep those diseases at bay. This protocol should be followed for all orchards regardless of crop freeze status.
  • Keep an eye out for fire blight strikes. Any blossom infections that may have occurred from the May 12 potential infection event should be showing now or next week. If you see them, cut them out.
  • Thinning is going to be complicated a lot by crop status, of course. For orchards that have no fruit or heavily damaged fruits (meaning more than 75% )do not consider thinning this year. For orchards with less than 20% damage I would consider thinning as normal this year. The question comes with orchards that have moderate damage between 25 and 75%. Not thinning those orchards may result in heavy set of small fruit that could promote biennialism, but trees are likely to respond well to thinners applied in the next week, given both the cold damage and the warm sunny, weather that we are expecting coming up. My tactic at the UVM orchard, which experienced moderate fruit damage between 20 and 70%, depending upon cultivar, was to apply a low rate of NAA thinner with a low rate of carbaryl insecticide. This could be a gamble – we have 70 varieties across the whole orchard and it is difficult to thin based upon variety even in a ‘normal’ year. This is not an uncommon problem for retail orchards to face. I do not have the greatest confidence in this strategy this year, and have difficulty recommending blanket sending recommendations to growers given the state of the crop this year. in the end, I would trust your gut – if you have a good crop thin it, if you have a moderate crop consider thinning it lightly as we can come back in later next week when we can see better the effects of both the frost and any thinner applications you may have applied.
  • Insect management-this will also differ, depending upon the state of the crop in your orchard. For orchards with a full or even a moderate crop, I would plan to manage your insect pests as normal this year. Petal insecticide sprays should have already gone on in most orchards. Inland orchards and cooler sites may be ready for a petal fall spray now. Normally our petal fall sprays are targeted at European apple sawfly, early emerging codling moth, and plum curculio. All of those pests are fruit feeders so orchards that have no fruit or are assuming to have very little fruit may consider omitting all insecticide applications targeted toward protecting fruit. The difficult situation comes where orchards have a low set of fruit where the expense of the application on a per bushel basis could be quite high but the value of the few apples you have is also high. If there’s any question about whether or not you have sufficient crop set in your orchard, I would go ahead and treat as usual. If you have no crop or nearly no crop , then you may consider omitting those insecticides. However, I would consider maintaining some coverage primarily for shoot and leaf feeding, lepidopterous caterpillar larvae. That may mean including BT sprays in petal fall, scab, thinning, or other sprays in order to keep down leps like obliquebanded leaf roller and tent caterpillar. In orchards with little to no crop, the great reduction insecticides used this year may allow beneficial populations to increase substantially, setting you up for a better IPM program next year. I would however not ignore trunk applications of Assail or another appropriate insecticide in young plantings to avoid issues with dogwood and other borers.
  • Nutrients-for trees with little to no crop nitrogen applications should not go on this year unless trees are under vigorous. For all other trees, fertilize as you normally would. For trees with little to no crop this year potassium is not likely to be removed in any significant amount because that is usually removed in harvested fruit. However, it is important to maintain or improve the potassuim status in your orchards to ensure that you have an appropriate amount of that nutrients going into next year when it is likely orchards, will have a heavy crop load. I would consider applying magnesium potassium fertilizers in the next month or so regardless of crop status.

That’s it for now. I hope to have a better understanding of the crop situation soon, but you all likely know where you stand on your own farms. I will continue to work with the Agency of Agriculture to see what resources we can bring to the industry in this tough year.

Take care,

Terry

Important: orchard / vineyard freeze damage assessments

The devastating freeze event that nearly all of us saw on May 18 will have a massive impact on the 2023 Vermont apple and grape crops. I have met with Vermont Secretary of Agriculture Anson Tebbetts and representatives from our federal congressional delegation and they are working on finding resources to help support affected farmers. We have been asked to collect as much data as possible to help inform these efforts.

https://go.uvm.edu/2023fruitfreezereport

The UVM Fruit Team has developed an online reporting form to collect this information. This is separate from any assessments that may be conducted for crop insurance purposes- if you are making a claim, please contact your insurance representative in addition to filling out this form.

We also recommend contacting your local Farm Service Agency to establish access to any potential assistance with this event.

It is important that we develop the best assessment of damage possible in the region to inform any efforts to leverage support. These data come directly to me and I will share with the Agency and other organizations anonymously. You may answer any questions that you wish to.

We are asking for general economic impact on your farm, as well as block-by-block damage reports. You can fill out those block reports as much as you want- there are fifteen blocks or cultivars you can report; if you want to report more, just retake the survey and only complete that section. Most important is to report potential crop value lost in the final section.

My graduate student Eli Wilson noted his protocol; for collecting damage in apples. The collection should be similar in grapes but you will be assessing damaged shoots as opposed to fruitlets. Feel free to modify your protocol as you see fit, you will only be reporting percent of fruitlets or shoots damaged.

Apple fruitlet damage assessment protocol.

Be sure to take note of:

1. Location on slope (Top, mid-slope, bottom)

2. Row orientation (North to South, East to West)

3. Cultivar

4. # of damaged fruitlets

Collect a total of ten fruitlets per tree from the bottom, middle, and top of the canopy. Slice the fruitlets in half (vertically) to assess them for damage, any internal brown/yellow tissue or seeds should be considered damaged. Record the number of damaged fruitlets out of ten. Repeat this protocol for every eighth tree in a row and for every sixth row of a block unless you wish to assess a specific cultivar in which case you should add this row to your assessment but not substitute it.

**Attached to this email are images of a healthy fruitlet and a fruitlet with minor cold damage do give you a baseline for your assessments. Any fruit with that level of damage or higher should be include in your damage report**

Figure 1: Healthy apple fruitlet

Figure 2: Damaged apple fruitlet

My team will be available and conducting assessments around the state this week and likely next. There is a lot of ground to cover and we cannot hit every farm so please consider conducting your own assessment and reporting you data in the form. I will be monitoring the form and trying to get to underreported areas as I can, considering my other responsibilities at this time of year.

Please reach out to me if you have any questions,

Terry

https://go.uvm.edu/2023fruitfreezereport

VT Apple IPM: Managing freeze-damaged trees

I spent a bit of the day fielding calls and assessing trees from a few counties after last night’s freeze event. Growers in the Champlain Valley largely escaped extensive freeze damage; I doubt Grand Isle County even saw a light frost. This was a textbook lake effect phenomenon. Inland and upland orchards or orchards in lower sites appear to have extensive crop loss, some likely will see a complete loss of crop. Here are a few items to consider as we pick up the pieces:

  1. Unless you had multiple thermometers in multiple locations and heights in your orchard, you don’t really know the temperatures that any particular tree saw. There has been a lot of extrapolating from neighbor’s stations which can be helpful, but not to the degree of accuracy that would tell you the critical difference between 30° and 28° (or 25° and 22°).
  2. Buds don’t read critical temperature charts– there are a number of factors that can affect bud hardiness, including cultivar, age, water or nutrient stress, etc. But we can assume that temperatures at or below 28° will start to show some real damage.
  3. At this time, the most important thing to do is to assess your damage visually. This is really easy to do as damaged buds will show by now. I sent this link yesterday that will be helpful to review again. Basically, pinch the ovule at the base of the bud with your fingernail or a razor blade so you cut it at the equator. The interior should be completely green with no browning or worse, blackening. This can be seen without intense magnification but growers my age or older ought to have your readers with you. I also looked at buds today with someone who is color blind and realized that that condition makes it had to see the damage, so if you are, have someone else do the assessment.
  4. Think about your strategy based on your freeze condition. Inland, and assuming your orchard saw 25° or colder? Go to your best spots- at the top of the hill, healthiest trees, buds collected head height- if you see extensive damage there, you can assume that the lower spots of the orchard are as bad or worse. In the Champlain Valley, your weather station said 29, 30°? Go to the low spots and assess, if you don’t see extensive damage then your better-sited trees are probably okay. Do a thorough assessment and write it down, especially of you will be applying for a crop insurance payment. I would start with 50 buds collected methodically and randomly from the canopy for each block and variety. If you have more than 50% damage, look more.
  5. If you do have extensive damage and you have crop insurance, contact your agent ASAP. Even if you think you don’t have damage, keep an eye out in the coming weeks. Weakened buds can abscise later, or fruit may develop frost rings that make them unsaleable as fresh fruit.
  6. Thinning could be really easy (no crop, no thinning) or more difficult, especially in blocks with inconsistent fruit set and levels of damage. All things being equal, trees will respond more easily to thinning chemicals after experiencing a freeze. If you have more than 50% damage, consider at most a light thinning protocol this year. More than 80% damage? Leave the thinners out altogether.
  7. My suggestion this morning to consider applying Promalin may have been a bit premature or at least lacking in further nuance. My thought at 4 am as I was looking at the temperatures was to offer whatever I could to growers who would need to source a material few to none of us keeps on-hand and get it on the trees within 24 hours. I was not thinking that a) there only existed nine bottles in the entire state, b) many orchards were at petal fall and so were past the phenology labeled for use of the product for this purpose, and c) orchards that got really cold and had 100% crop loss or severe damage from temperature below 24-25° would not respond- a dead bud is a dead bud. I do plan to collect data at the handful of orchards who applied Promalin to see if we can add to the fairly sparse dataset on its efficacy in these situations.
  8. If you have no fruit, trees still need to be managed. The important things to stay on top of are apple scab, fire blight if you see any, foliar insects on young trees, and wood-damaging insects like borers. Keep your fungicide program up for the next month or so (is apple scab season ever going to end, despite us seeing next to no scab?). Keep weeds away from trunks, especially if you will be backing off insecticide sprays for fruit feeders like codling moth or apple maggot that would normally help manage borers. Back off or eliminate nitrogen fertilizers- fruit really slow the vegetative growth of fruit trees so when there are none, the trees can be excessively vigorous. Consider applying Apogee or Kudos to reduce vegetative growth and stiffen up cell walls in vegetative shoots to reduce canopy size and make shoots less susceptible to fire blight.
  9. Start thinking about your marketing for this season. Many of the most affected orchards are small pick-your-own or retail operations. They may be side gigs or a family’s main income. Most are diversified to some degree. Consider whether you’ll need to buy fruit in and provide customers some other reason to visit the orchard- foliage hay rides, corn maze, pumpkin patch. There are fruit in the region that can be brought in, so start making those connections and thinking about how you’ll keep cash flow this fall.

I have been a member of the Vermont orchard family for almost 30 years now, and I am always impressed with the camaraderie and collective sense of purpose that we share. These events can be major hardships, potentially even devastating. Let’s see how we can help one another and keep this incredibly important industry, and each and every farm within it, afloat and even thriving after a challenging, somewhat unexpected event that could have affected any of us.

Please reach out if you need anything,

Terry

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.

Promalin as a rescue treatment for frost damaged apples

As I scan the temperatures around the state on Weather Underground this morning, it looks as I expected, that most orchards are likely fine (no damage) or okay (a little tolerable damage) after the freeze event we’re in. Some orchards however, especially inland and upland, and really especially inland and lowland (in lower areas where cold air settles), may have experienced substantial damage. Promalin plant growth regulator is labeled and has shown some efficacy when applied to trees at bloom to early fruit set for maintaining fruit development after a frost or freeze. Promalin is a gibberellin and cytokinin PGR mix that essentially fools the fruit into continuing to develop in the absence of a hormonal signal from seeds that were damaged or are not present if the ovary was damaged. Applications within 24 hours after the freeze are most effective.

If your orchard experienced temperatures below 28°F, consider contacting your agrichemical dealer asap this morning and applying Promalin. Label rate is 1-2 pints per acre in 75 to 150 gallons of water per acre.

Terry

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.

VT Apple / Grape IPM: Frost considerations

Vermont orchards and vineyards are in varying states of vulnerability and likelihood of frost damage going into tonight’s expected cold event. At UVM orchard in South Burlington, we are at about 50% petal fall on McIntosh and the vineyard is at about one inch of shoot growth; inland and upland orchards are at or even approaching full bloom and vineyards are hovering around bud break. All orchards in the state are at risk for blossom tissue damage with temperatures at or below 28°F, and potentially a full crop loss around 24-25°F. Vineyards with fully emerged buds (1-2 leaves or more) are at the same risk, but those at bud burst or behind are less susceptible to damage and may do okay even into the lower twenties. In the Champlain and Connecticut River Valleys, expected lows are in the 30-32°F range, and orchards should be okay except possibly in low-lying pockets. Inland and upland, this event will likely show where site selection leaves orchards at most risk. Some inland orchard sites are calling for lows in the 24-25° range- that could cause substantial damage. Winds are expected to calm down overnight which lends to increased frost risk in low areas where cold settles. This does mean that methods that stir up air inversions may help- wind machines, helicopters, etc.- but few of our farms are set up for that aside from the lone wind machine I know of in Shoreham which I expect will be running in the early hours of tomorrow morning. There is little you can spray to affect frost tolerance of plants- some materials like some copper formulations and some potassium fertilizers are either labeled or purported to improve bud hardiness but not when sprayed right during a cold event and the science isn’t very good on that, either. Not to mention that sprayers will be icing up if you try to spray at 10-11 PM or later when the winds calm down, as that’s when the cold (below 32°, when spays will start freezing) is expected.

Growers could try burning round bales in the lowest / coldest parts of the plantings, starting around midnight or whenever the temperature starts to get down to 28°, but that isn’t known to be especially effective as the heat needs to radiate across a large area to really have any effect, and the smoke and near-range heat from burning bales can damage developing buds. If you have a Frost Dragon or similar device, tonight would be a good time to run it. But who has one of those in Vermont (I’d love to hear from you if you do).

The best case for most may be to wait this out and to conduct an assessment tomorrow afternoon or Friday. This article provides some good pictures of damaged tissues to compare yours against.

https://www.canr.msu.edu/news/assessing_frost_and_freeze_damage_to_flowers_and_buds_of_fruit_trees

Understanding the extent of damage will help with reporting for crop insurance purposes or to adjust you fruit (apple) or shoot (grape) thinning needs.

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.