Season 7, Episode 3: Green Tip Game Plan

Don, Kari, Shan, and Greg highlight the very first stages of spring as green tip begins to emerge around the state in apples.

Music Credit: “The Raven and the Swan” by Josh Woodward is licensed under a Attribution 3.0 United States License. Courtesy of FreeMusicArchive.org

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Flight Seasonalities of Main Fruit Pests During the Growing Season

Transcript

Welcome And Season Kickoff

SPEAKER_03 0:07

Hi again, everybody. It's the Dr. Tree Fruit and Dawn Podcast. I'm Don Seafert. I'm here with Dr. Carrie Peter. Say hi, Carrie.

SPEAKER_00 0:13

Hi there.

unknown 0:14

Dr.

SPEAKER_03 0:15

Greg Krawchek, say hi, Greg. Hello. And Dr. Sean Kumar. Say hi, Sean.

SPEAKER_02 0:21

Hello, everyone.

SPEAKER_03 0:23

It is uh Tuesday, March 31st. We are almost in April, almost April Fool's Day. Uh, but this is not a joke. We have plenty of fun things to talk about today. Uh, Carrie, if you'd like to go first, why don't you get us rolling?

SPEAKER_00 0:37

Okay, folks. Uh we are uh at the beginning of the season. Trees have broken dormancy here down in south central Pennsylvania. I'm really seeing probably getting close. If not, we're at half inch green tip down here in Adams County. And so, and just as a reminder, with green tip, with breaking dormancy, this is when the apple scab spores awaken, are start to be mature and ready to be released from those overwintering leaves. Um, so far this season, we've already had a kind of an apple scab infection event last Thursday, Friday. However, I'm not too worried about that because it sounds like everyone had covered up with copper at that point. So copper would have been protecting you. So it's nothing to worry about, I believe, at that point. Also, as a reminder, apple scab spores, the mature spores don't all release at once. They gradually trickle out and then they peak around late pink bloom and then they drastically fall off at petal fall. Uh, and so right now we're at at as far as disease pressure, low disease pressure, um, because the amount of noculum out there is not terribly high. It's the it's the nature of how apple scab works. We've monitored apple scab for many years and it's the same trend. They trickle out in the beginning, it peaks with the max number of spores that bloom and then it falls off. So, right now we can be conservative, which is why I want to emphasize that even though we had a scab infection event last Thursday, Friday, according to the models, I'm not too worried about it because everyone should have been covered up with their copper by then. Um, this week, though, with the really warm temperatures, the green tissue is advancing. So this is vulnerable green tissue now. And right now, the models are saying April 1st and 2nd for a scab infection event. However, we know how Mother Nature works. So this may or may not occur, or there may be thunderstorms that pop up because of the warm temperatures we're having. And at this time, because of those said warm temperatures, we only need six hours of leaf wetness. So those thunderstorms could easily give us trigger an apple scab infection event with just six hours of leaf wetness. With that said, people should be probably getting out there and covering up, and you can be conservative at this time of year. Here at Freck, what I'm recommending is a tank fit um tank mixing, a rain fast mancozeb plus a micronized sulfur. So three pounds of um three pounds to the acre of the rain fast mancazeb, whatever of your choosing, whether it's rope or rain shield, diphane rain shield, manzate pro stick, um, just some kind of rain fast mancozeb because the longevity of that will pay off, especially if we're getting frequent rain events over a period of days. And then sulfur. Sulfur is another good broad spectrum, especially micronized sulfur because it will disperse a lot more easily and covered and cover the green tissue much better. As far as the rates at this time of year, I'd say anywhere from probably six to ten pounds per acre of the mycronized sulfur. Um, you don't have to go too extreme with it, especially when you're tank mixing with the mancazeb. Uh, you can also tank mix mancazeb and seal it uh, or um just use mancazeb by itself. Again, you can be conservative. There is no need to panic as far as seeing the green tissue and getting out there. Um, disease pressures on the lower side because the number of spores aren't out there and to the extreme. Now, for folks that may be a little more south in here, and definitely I know there are areas that are blooming south of here, but you might be at tight cluster. Um, so tight cluster might be creeping up on you, and just as a reminder with tight cluster, this is when powdery mildew starts. So we need to be paying attention to these dry days surrounding tight cluster. So, options you can use is again use your rain fast mangaza because that will take care of any scab that can pop up when um there's a rain event. Uh, so you could focus on having more of a um powdery mildew focus for some of the products, um, but some good products that are good for both scab and powdery mildew are like Axios or Sevilla, um Procure. Uh, if you really do struggle with um, those are just a couple that I'm naming off the top of my head. If you really struggle with powdery mildew, you may want to go with something stronger. You could go for a high rate of sulfur of mancozeb and then a high rate of micronized sulfur. Go up to 10 pounds, maybe 12 pounds per acre if you're struggling with powdery mildew. Um, for the organic folks, sulfur is your best friend, but you can also use potassium bicarbonate or eco swing is also another good option. But tight cluster is that time, don't let it sneak up on you. Last year was a really tough year for powdery mildew. I think the year before was a tough year for powdery mildew. We often forget about these dry weather days that they are great weather for another disease. It may not be a good disease for scab, but it's a good disease for powdery mildew. Uh, and so it's something you need to be juggling. We'll probably talk about it again in the next episode with the with the rate of this warm weather and how fast the phenology is going. Um, but it's just for people to be on their toes. So again, just as a reminder, um, it sounds like, or I should say, the models are saying April 1st and 2nd for an apple scab infection event. But when I look at the radar, the percent chance of precipitation keeps fluctuating. However, be prepared for it and also be prepared for the days after. So April 3rd, 4th, and 5th are also showing some very um unstable weather, especially on the 5th right now. When I was looking at the weather, it's showing almost like close to an 80% chance of rain on the 5th. So whatever you are doing this week to prepare for scab, it'll probably cover you for whatever may happen over the weekend. Um, and then next week is a different story. So we will cover next week when it comes, but that's just look through from now until April 5th. Um, this is when I'm I'm living five days at a time right now. So when it comes to the the weather and conditions. Uh and so yes, so that's it. So just um we are off to the races officially. I mean, we mother nature is ready to go. I thought she was gonna give me a break, but alas, she is not, as I sit here sweating in my office when it's I think pushing 80 degrees outside right now. So, Dawn, um, any questions or thoughts? Did I miss anything?

SPEAKER_03 7:24

No, I think you covered all the bases. I I was obviously have been doing the phonology stuff uh on Mondays, and that should be posted today of the recording of this. Uh and I I recorded all my phonology stuff, and then I went, well, this is gonna be useless by the time it actually gets reported because it's gonna take off like a shot the second I finish, second I leave the field. Um, so yeah, that's kind of I think where we're at, weather wise. It's whatever we say today or tomorrow is gonna be gone by the day after.

SPEAKER_00 7:56

So yeah, yeah. So I mean, right now our peaches aren't really moving, neither is our tart cherry. So I've really nothing to report on tart cherries or peaches. Um, I do know apricots are blooming out there. I've seen them. Hopefully they'll be a crop, but we have had some precarious low temps. Um but from the disease perspective, you know, well, you know, this this is you know, uh uh this is an event to be concerned about, but again, you can still be conservative um with these conditions that we're seeing. So so but that will all change very soon if these warm weathers can warm weather continues. So awesome.

SPEAKER_03 8:33

Thanks, Gary.

SPEAKER_00 8:34

All right.

Moth Traps And Degree Day Timing

Pear Psylla Oil Sprays Now

Petal Fall Strategy And New Labels

SPEAKER_01 8:35

Uh Greg. Oh well the spring is here. Actually, some of the bugs are flying. We got because we're monitoring for a lot of different species, we got the first red banded and spat attention from leaf miners in our traps, pheromone traps already. Uh those two pests, I mean, I don't know a single location where they are a problem, but because they overwinter as adults, they are the first one to show up in the spring. So, yes, we officially got them last week in the traps. So something is flying. Something that is probably more interesting is the oriental fruit moth and codling moth. The general rule is that oriental fruit moth starts flying around the bloom of peaches, an apple and codling moth are supposed to start flying when apples are in bloom. To put it in perspective, last year in 25 oriental fruit moth started flying on April 14, which is two weeks from now. And at the time we were at about 290 plus degree days base forty-five. Where are we right now? We are at us and this is according to newer, we are at 226 degree days today, and we will be at 325 by Sunday. Well, basically, if the degree days are good indicator, and this is not the only factor that influence when the moths are flying, we should have Oriental fruit moth flying sometime later this week. So, will this be the biofex? Well, yes and no. The reason why I'm a little bit reluctant to say, oh yeah, we will have them, is that basically starting from Easter Sunday, the temperature, at least according to forecast, and Kenny mentioned this number of times, forecast might change. Starting from Easter Sundays, the highs for the days are 59, 53, 63, 59, 65. Those are the highs for next week. If that holds the chance of any OFM activity observed next week is almost zero. They will not be flying when it's that cold. It doesn't mean that they won't be there, but they won't respond to the pheromone, they won't be observable in the trap, and so on. So the lesson well, put the traps out if you don't have it already. I talked about it last time. We really need those traps in the orchards now. See what happens, and then make a decision how important the flight that most likely will happen this Thursday, this Friday, maybe Saturday. You might see them on Easter Sunday because you'll be if you check traps on Sunday, you will be checking what actually happened on Saturday. And Saturday is supposed to be 81 according to the forecast. But then, if we don't have any flight for another week, then the question is when is the biofix? Are we worried about this 1, 2, 3% of moths that started flying earlier on, or we will define biofix as the continuous flight, which I think will start happening from Thursday, April 9th. I think the latest for the biofix, but again, I'm guessing, and you might say, Well, you told us so. I don't know. I think we will have the continuous flight of OFM by the end of the week after Easter. End of that week. So we'll see what happens. Kodlink moth. Uh our biofix last year was on April 29th on 28th. At the time, we were at 313 degree days. Those degree days for Kodlink moth use a different base than for Oriental fruit moth. Because for Kodlink Moth the lower threshold is 50, for OFM it's 45. So right now we are at 142. By the end of this week, we're supposed to be at 216. So I think the earliest will be second part of April that we might start seeing codling mouth. Saying this, having trap in the orchard, well, zero is also a number. And it's nice to have uh zeros before you start catching something, then you know that you really got the real biofix. So if you're putting OFM traps or you have already them, maybe putting traps no later than by mid next week for codling moth is also a good idea. So this is for monitoring. You know, of course, you can add other traps, but traps for Taftet should not go before the Bloomon apples, oblique few weeks after Bloomon apples. I don't know how many people really monitoring for borders, Dagwood Border, Pitch Tree Border, Lesser Pitch Tree Border, those are less important. However, if someone is interested in the flight or see the potential problem, it might be a good time to know start thinking about it. Nothing really needs to be out before the bloom on apples, other than this OFM and potentially coddling move. Everything else is kind of secondary. So that's about monitoring and how the weather can play tricks with us. What about stuff that we don't monitor using traps? Well, I guarantee you that this week, if you go to the pear orchards, there will be plenty of persilla adults flying in the orchard. What can be done about it? If they flying, they also mate, and Persilla can start laying eggs. This is really this all practice that we recommend for a number of years. That this is the time that you should go and spray with oil. Anytime, anything around one and a quarter, 1.5% oil sprayed on peaches on pears right now will help to reduce the number of eggs that females are going to deposit. It will not eliminate them completely, but will reduce, and this will help later on during the season when we try to have those generations synchronize better, and then all whatever we do against Percilla will be more effective. So if you didn't do so, spraying oil right now is a very good thing. Well, again, will it will it rain tomorrow or will not it rain tomorrow? Depends which forecast you look. Some forecasts saying that it's gonna be rain for 20 hours, starting today at midnight. But again, it's it's a forecast thing. Anyway, spraying oil will reduce the number of eggs, it might also kill some eggs. But if you can squeeze one oil and then within 5-7 days, oil plus pyretroid, but the pyretroid has to happen before you get to the white butt stage on pearls, then you might have a much better results in controlling persilla later on during the season. It's all about making the generation more synchronized through the season and this way making everything else working better. On apples, well, oil also is not a bad choice if you know that you had some European red mites, that you had some aphids, that maybe potentially you had some Jose scale. Then going with the oil, and in this case, again, the closer you get to the tight cluster to the pink, the concentration should be lower, but anywhere from 2-3% to 1%, it's a good shot, it will help, it will keep those pests that I listed in check. This is not the most effective spray, but will help. Will help later on. Do you need to spray any insecticides? Uh, I keep saying this for a number of years, that with the assortment of different products that we have a viable that can be sprayed at petal fall on apples basically, other than European apple sofli, which in most cases is not a problem, everything else can be controlled at petal fall. So I would not too worry about spraying insecticides on apples before after petal fall. And this is not only because it will obviously help to protect bees and native pollinators, but there's basically no need. And you know, you know, I said this also a number of times that you don't need to kill the same insect twice, and most of them will the present that you're trying to control now, will also be there at petalfall. That's why I think petal fall spray is the one that really we need to prepare and be ready. Um saying this, there is this new product I mentioned last time called The Valgo. Uh, I don't know what the pricing is for it, but petal fall might be a perfect time to use this product as it should help us with plum curculio, European apple sofly, oriental fruit moth, stingbox. Well, it even has mites on the label. I don't buy that recommendation, however, it is on the label. So even if this is only a suppression, this might be all you need at petalfall if you worry about mites, European red mites. So basically, this might be a good time to try it, it might be a good time to use it. Again, I'm not advertising for this product. If you go with your regular Acale at 8 ounces at petalfall or Avant Plus, Agrimac plus 2 3 ounces of Assayle mixture, they are as good as. When we go to the Twilight meetings, which I'm assuming Dan or Kerry will mention them a little bit earlier later. The Valgo is the first insecticide with the new model for the label. And this is the one that you actually have to go on the internet. You have to go through the at least two different steps to make sure that at the moment you are applying the Valgo, you are legal to use the Valgo. That's all about Endangered Species Act, ESA, and all the new insecticides are required to have this kind of restriction. So if you can't use the internet, I think you cannot use the Volgo. But this is something that if you go to the label, you read through the label, it will basically give you steps, what needs to be done, how, and so on. But this is something to remember. Other than this, uh I mean, one more thing that maybe on apples that if you really had a problem that you detected at harvest, it might be a good time right now to go against San Jose scale. But this is very rare situation. Most of the people don't have a problem, and oil will help. Will not provide excellent control, but it will help, and San Jose can be also controlled later before it actually attacked fruit. So this is one of those paths that yes, it can, but there is also time to control it later. So with this, that's all updates I have. Unless there are any questions.

SPEAKER_03 23:55

No, I think that covered pretty much everything and uh really appreciate the update as always. So and why don't you give us your report?

Phenology Update Across Pennsylvania

Thinning Fertility And New Plantings

SPEAKER_02 24:04

Sure. Uh thanks, John. Uh I just wanted to give everyone a report about uh the phonology and where we are at in different parts of the state. Uh finally, after a lot of cold weather, we are in the season, so to speak. We have warm temperatures all this week and next week, and things are gonna move quite fast. And so we were already at Green Tip uh close to about a week ago in Adams County. We are slowly getting into, and a few days later, I think in in Berks as well. And uh this week we are slowly getting into uh green tip in our region in uh state college area, and I know that uh in the western part of the state and northern part of the state in Erie uh n northeast that uh it'll still be about a week or week and a half more uh in order to see green tip uh depending on the temperatures that you've had. But that's where we're at. Uh and for peaches, uh at the southern part of the state, uh we a lot uh some of the varieties we already see them at pink, and uh so very soon the peaches will be into uh thinning season, so to speak. So if you're using uh thinners for peaches, uh the only registered chemical thinner is a seed, and so uh you can use a seed with rates between 300 to 600 ppm, which is 10 to 20 ounces of the product for thinning, starting from pink to petrol fall in peaches. It uh so first look at the damage you've had based on uh uh damages that we've seen in different parts of the state. On average, we're seeing around 30 to 50 percent damage from the winter uh and from the cold that we've had. Uh that that means that you still need to take off quite a bit more in your peaches because you need to set about 15 percent, 10 to 15 percent of your crop for successful uh peach crop. So you still need to thin and lower rates of a seed uh will uh are safe to use. So you can use something like 300 or 400 ppm or 10, 12 ounces, 13 ounces of the product to the acre. And of course, based on some of the work that we have done, increase the water volume uh that you spray per acre to about from 100 to 150 gallons if you want to see a slightly additive effect of that increased water volume on thinning uh that we have observed. But for peaches, between 10 to 20 hours, 2010 to 20 ounces of the product I think would be good to use. We're slowly getting into pink, so they might be ready for thinning sometime next week, depending on your location. Uh, so you can apply anywhere from pink to petal fall. I think applying it full bloom will be best for peaches and peach thinning. And so if you have a large uh varied block, then try to select the variety that blooms somewhere in the middle of that time frame. Uh and so you'll have varieties right from pink to petal fall, but you'll have the variety that sort of blooms in the middle uh at full bloom, and then you can spray the entire block and you can cover uh the entire block in that time frame uh in that way. So that's for peaches for apples. Uh, we're still a little bit away from uh pink and bloom, and so uh so but still it's time to I think think about your blast and thinning strategy for this year. Again, check for damage, check check if your kings are alive for some of the varieties because of the cold that we had about uh I think uh at this point it was two weeks ago. Uh we had a warm spell and then we went back cold in Rock Springs. I know that we went to about 10 Fahrenheit uh one night, and so we lost a lot of the kings and some of the varieties. So make sure you check that and adjust your thinning strategy accordingly. But it's good to think about your blossom thinners, your lime sulfur uh 2% and stylate oil 2%, as well as think about ATS and think about ordering that and having it ready because it'll still be a couple of weeks or a few weeks, depending on how the temperature goes. But uh best to be ready with them as for blossom thinning your uh apple crop as well. But uh that is the update. Hopefully, you're getting through uh pruning and sort of uh go getting through the final stages of pruning your different apple blocks. Uh I'm sure we're all uh still have quite a bit left to do of pruning, and you're all are getting getting to it, uh especially as the temperatures are getting better. Uh, but that's that. As far as fertilization, I think that uh a lot of fertilization, especially uh uh nitrogen uh and liming liming, especially you can start now. You can lime your soils. Uh you can also do it in the fall, uh, and because it gives it more time to sort of get get incorporated more. And so if the recommendations ask for lime, then you can lime your soil. Make sure that for honey crisp you're liming only with dolomitic lime, sorry, with calcitic lime, not dolomitic lime, because dolomitic lime contains magnesium, and you don't you don't want to be adding more magnesium to your soil, especially in honey crisp blocks, and so use calcitic lime when liming your soil. And as we get closer to bloom, I think you can start with uh your fertilizer applications, uh, especially micronutrients like boron, which is very important for uh during bloom and uh pollination and fruit set. And so uh we're still about a week, week, week, week and a half away from starting some of our major fertilizations for the year, but we can always get started with lime, I think. And uh with new plantings as well. I think people are starting to plant new blocks in the temperatures, uh, the weather looks great this week and next to get uh some of our new plantings in. And so that's something to think about. About seven to ten days uh pre, you can apply glyphosate or something, some burn down herbicide to clear off the strips, and then uh seven to ten days later, you can you can uh uh plant your crop. Make sure if for new blocks you're incorporating your lime and other nutrients like monoammonium phosphate or diammonium phosphate to get your phosphorus in, because phosphorus takes time to be incorporated to the soil and takes a few years for it to be uh taken in by the tree as well. So make sure you do all that and then plant plant your trees and follow up again with uh pre-emergent herbicides that you can use uh so that you're getting your weeds under check uh early at early on as well. Uh and that's it for me up as updates. I'm sure you all are checking almost every day uh as to where your uh trees are at. And this week and next week expect them to move uh somewhat quickly because of the warm temperatures that we have. But as as in the next two weeks, I don't see any concern for frost, particularly in our uh in our region based on the temperatures that I'm seeing. So hopefully fingers crossed that they stay that way until we get through bloom and fruit set.

unknown 31:50

Thanks.

Spring Meeting Dates And Wrap Up

SPEAKER_03 31:51

Fantastic. Well, thanks for the update, Sean. Uh Carrie, are you doing the spring meetings or am I doing the spring meetings?

SPEAKER_00 31:58

Uh well, so we don't have all the spring meetings finalized. So so we aren't ready to advertise the spring meetings yet. Um we're still in the process of finalizing a couple locations.

SPEAKER_01 32:11

I mean, we have dates. We have dates.

SPEAKER_00 32:14

Yes. Oh, the location. Okay, so location, we can give dates. So I I've got my list up, so I will be happy to share where people need to be um putting a mental note and maybe a pin in their calendar. So, first, on Tuesday, April 28th, we'll be in Lancaster. And so this will be occurring from 6 to 8 p.m., just to let folks know that's the typical time. Uh on Wednesday, April 29th, we'll be somewhere in Adams County. Um on Thursday, April 30th, we're going to be somewhere in Franklin County. Uh on Monday, Monday, May 4th, we're going to be somewhere in the central Susquehanna Northeast region. So we aren't sure yet, but that's the location. Um Tuesday, May 5th, we we're going to be in the southeast region, and we do have a location, and that's going to be Lynn Villa Orchards in Media, Pennsylvania. So it's on Tuesday, May 5th. Uh, on Wednesday, May 6th, we're going to be in the western part of the state, and we do have a location for that, and that's going to be Dawson's Orchards in Enon Valley. And then Thursday, May 7th, in the morning, this is going to be a crazy day, but in the morning, we're going to be in Erie County at Birch Farms Country Market. Um, and that will probably be a like 10 to 12, uh 10 a.m. It's going to be a morning meeting. And the the northeast, the northwestern corner of the state, those folks, they know the drill. So that's going to be a morning meeting. And then we're going to get in our car and we're going to be driving to Bedford County. And so we're going to actually have our Appalachian region meeting that evening, early evening in Bedford County. So we're actually knocking out two meetings in one day on Thursday, May 7th. And so that meeting that's going to be in Bedford, the Bedford County region will be a smidge earlier. It probably won't be at 6, so probably be at 5 or 5:30. Just because those of us have been traveling all day and the previous day will want to get home before midnight. So back to Biglerville before midnight. So that is the schedule at the moment as far as days. A couple locations have been um have been finalized. Um, but as it becomes finalized, we will share with you folks um with every podcast when we get the meetings, spring meetings. So um so just stay tuned. But we definitely have the dates figured out.

SPEAKER_03 34:46

So awesome. Thanks for laying those out for everyone, Carrie.

SPEAKER_00 34:50

Yep.

SPEAKER_03 34:51

Uh and I think that's all we've got.

SPEAKER_00 34:56

Yes. And so since we've kicked off the season, we are Don, don't correct me if I'm wrong, we're gonna try to go on weekly, weekly schedules here to be able, um, now that the season's here, we're gonna get back on our typical regime of giving weekly updates. And so, and just to let folks know, um, this coincides on my end with weekly disease updates via email. Um, and and then I'm also doing alternative ways for folks that don't use email as well. So we're trying to get the information out as as broadly as possible.

unknown 35:33

Okay.

SPEAKER_03 35:34

So we will see you all next week. Say goodbye, everybody.

SPEAKER_00 35:39

See you later. Good luck.

SPEAKER_03 35:41

Bye.

SPEAKER_02 35:42

Goodbye, everyone.