Crop Talk by IAS – 08/12/26

As corn and soybean crops move through grain fill, agronomists across Iowa are keeping a close eye on late-season disease development, insect pressure, nutrient deficiencies, and decisions around potential second-pass fungicide applications. While overall crop conditions remain favorable in many areas, conditions still matter field-by-field as disease risk and pest activity continue to evolve.

In this week's Crop Talk by IAS, the team shares boots-on-the-ground insights from across the region, including what we're seeing in the field right now and what growers should watch next as we move deeper into August.

In this episode, the team discusses:

• Current disease pressure across Iowa corn fields
• Tar spot outlook as fungicide residuals begin to taper off
• Gray leaf spot, northern corn leaf blight, common rust, and bacterial leaf blight observations
• Japanese beetles, corn rootworm beetles, aphids, and other insect activity
• How growers are evaluating second-pass fungicide decisions
• Crop stage considerations when assessing fungicide return on investment
• Late-season nutrient deficiencies showing up after a wet growing season
• Benefits observed from nitrogen stabilizer programs in 2026
• Why tissue sampling and field scouting remain valuable late in the season
• Fertility planning opportunities heading into fall
• Using this year's observations to prepare for the 2027 crop season

As harvest planning approaches, now is a good time to be in the field identifying deficiencies, documenting problem areas, and discussing fertility strategies with your agronomist. The information gathered today can help guide decisions for next season.

Featured this week:

• Nicholas Giesseman - Host and Eastern Region Agronomist 
• Nick Thompson - Southwest Region Agronomist (Ellsworth) 
• Owen Heetland - Northwest Region Agronomist (Cleves)
• Erin Ricker - Eastern Region Agronomist (Masonville) 

🎧 Listen now
Have a question for the team? Send it to CropTalk@InnovativeAg.com

To learn more about Innovative Ag Services and our agronomy services, visit InnovativeAg.com/Agronomy.

Produced by IAS Communications in partnership with My Four Creative.

Transcript

Nicholas Giessman 0:00

Welcome to Crop Talk, brought to you by Innovative Ed Services, and this is our Field Scouting special. Each week from March through October, our agronomy team shares timely, boots-on-the-ground updates from across the IAS geography so you can make confident decisions as the seasons change. Today you'll hear a quick regional update from our IAS agronomist, including what we're seeing in the fields right now, what to keep an eye on next, and a few practical scouting reminders you can put to work this week. But we're going to get things kicked off with a little update from our western region. I'm going to kick it to Nick Thompson. What do you got for us? Thanks, Nicholas.

SPEAKER_02 0:50

This is Nick Thompson over in the Ellsworth location. Wrapped up fungicide last week, at least those that were doing first passes. We're still out scouting for disease, as that's not going to go away until the crop's out. But in terms of disease pressure, I would say around here we're sitting pretty good. There was a lot of fungicide that went out, and I feel like that stopped a lot of the outbreaks that we could have had. As you walk through the fields, you'll still see some gray leaf spot, maybe some northern cornleaf blight. But the biggest thing that I've probably been noticing the past week has been bacterial blight, which we can't do much about that at this stage. So right now, my biggest pressure is probably going to be bugs. The bugs this year have been very strong in this area, specifically Japanese beetles, but there is some heavy corn rootworm beetle pressure that in maybe some corn on corn fields or just notorious fields for having corn rootworm in them. As we reach the milk stage, we're about four inches above our year-to-date average in terms of rain. And it's kind of tapered off from the wet June and July that we have had. We got some rain earlier today, but uh it only amounted to about three-tenths of an inch. So for right now, we're sitting pretty good in terms of there's a lot of moisture underneath the ground, but I don't see a whole lot of areas in this area that are just completely ponded out. That's everything that I have here for the west side, and I'll kick it over to Owen on our northwest.

Owen Heetland 2:30

Thanks, Nick. This is Owen Heatland from the Cleves location covering Hardin, Butler, Grundy, and Franklin counties. I like a little bit of the same thing. Got good growing condition. Corn and beans both look pretty good. Um, have you know pretty much finished up first pass fungicide. Do have a couple guys going on second pass fungicide, but the rain the last week and a half has made that really, really tough. Um, some going on with airplanes, some waiting. Um, as far as scouting goes, have not seen a ton of disease, but with the rain and the heat we've had, extended periods of leaf wetness. I would anticipate that we would see tar spot start to come in. It has been a later season disease around here, which has meant it hasn't caused as much damage in the past years, but it's something to continue to look for. Haven't really found any of it yet, but I do anticipate that you know most fungicide was on. We're looking at 28 days ago, 21 to 30 days ago, that residual will start to run out and we will start to see some disease show back up. But especially early corn, as we get into dough stage, we probably start to run into a time frame when it's beyond where a fungicide is going to help us. So it's something still to definitely look at as we scout and then know the mature maturity of the corn. Have also started to see a slight amount of nutrient deficiency as we've been not saturated but wet most of the season. We've had another two to two and a quarter inches in the last 10-ish days with rain predicted for pretty much the next seven days. Um, it's something to look at. And then, as Nick said, lastly, we are starting to see insect pressure. Most of the bean fungicide was sprayed with an insecticide, which seems to have done a good job. And don't see a ton of aphids, but mostly Japanese beetles and then root worms and corn. And so, as you're out there looking at corn, the biggest thing to look at is rootworms more in preparation for next year. If you continually see extended diapause, which is the biggest issue around here, you know, something to think about moving forward is a trade on bean stubble and insecticide on bean stubble, or maybe a corn, corn, soybean rotation to get rid of that extended diapause and just knowing which fields have it, which fields don't, um, so we can make a plan for the future. Other than that, I think the crop in this general area looks pretty good. So with that, I will move it on to Aaron.

SPEAKER_00 5:00

Thank you, Owen. I'm Aaron Wrecker at the Masonville location. I covered Becanan, Delaware, and parts of Fayette and Clayton County. We have gotten our fair share of storms the last couple of days. There's a good stretch with hail damage and some down corn from the wind. I didn't see much from green snap. I'd say most of it was goosenecked. Um, but even with it being goosenecked, we need to remember that that corn plant is now going to focus its energy on throwing those brace roots down to try to get it back up instead of using it towards Greenfill. I know that they're calling for some more storms later this week, but hopefully it will be minimal. We are getting fungicide wrapped up at the airport. For the farmers who haven't put a fungicide on yet and were contemplating on doing one. If you got some hand damage, it might be a good idea to get some fungicide on to try and help keep that disease pressure as low as possible, especially because that corn plant will be more susceptible to it now. As always, if you have questions, feel free to reach out to your local agronomist. With that, I'm going to pass over to Nicholas and our Southeast region.

Nicholas Giessman 5:57

Thank you, Aaron, for that update. This is Nicholas Giesman out of the Cascade location covering Dubuque, Jackson, and a little bit into Jones County. Kind of the same thing Owen, Nick, and Aaron said, you know, talking about not a lot of disease pressure right now, but definitely I think we're getting set up to see some tar spot rolling here. There's the gray leaf spot, there's the common rust out there, but I definitely say it's going to be coming in a little later this year, kind of like it has last couple years. Bugs, uh, most of our fungicide has been sprayed with insecticide, but looking out there, there is some more rootworm beetles flying around the corn now, more aphids, some more Japanese beetle, like they said. But for the most part, crops are looking really good. I know the excessive amount of rain, you are seeing some deficiencies in nutrients, like Owen said, a little bit of nitrogen, a little bit of sulfur stuff just kind of showing up with all that moisture that we had all season, but looking looking really good going the last you know few months before harvest. So I think it's a really positive you know note going in through August here. Owen, how do you manage the second pass? You know, if you're out looking for disease and you start to see something, when is your cutoff to do we go back, do we not go back? What's the what's your thought on making that call?

Owen Heetland 7:07

So I would say around here, probably maybe the end of this week or beginning of the next week. I mean, the biggest thing you're looking at is crop stage and maturity of the corn, because I'm assuming we're talking mostly about corn. So I would say later corn is probably gonna pay better, and then every year is is different. So we've got some trials out there, you know, to see whether it's gonna make a difference or not. But you know, some guys are on the thought process of I'll just use two generics because that will be cheaper and I'll just plan on spraying it twice. Some guys are using a branded and then a generic to keep cost down. Um, so there's a lot of different things to look at and try. But really, what you're trying to do, the the thought process, the goal is on a late corn, is to extend the photosynthesis of that corn as long as possible. So you extend the grain fill and create a larger kernel, heavier test weight, better standability, assuming that that late corn will be the last corn you combine. And so you need it to stand until November. You don't necessarily want to combine 14% corn in November because you're gonna have a head loss. So the biggest thing is planning out even pre-season, you know, what your maturities are, when you're gonna harvest them, and then you can start to plan on what you would spray a second time. As I've told many customers, I can't tell you that I would spray a hundred day or even a hundred and three day twice with fungicide, but I would probably spray 114 or 115 day, which is pretty darn late around here now in Cascade and Ellsworth. Maybe it's later than that. You know, that's a question for you, you guys. Do you have anybody doing a two-pass and and what are they looking at or how are they thinking about it?

Nicholas Giessman 8:52

There's definitely a few growers that are, and you know, some are running that generic two product, so they're running the generic up front, coming back and putting them together to you know run that over the premium product first or generic second. A couple guys that are worried about standability to harvest are making that decision now to, you know, hey, we're gonna go spray, like you said. Spray our, you know, these fields that are gonna be last. We we know we're not gonna get there probably till November if everything goes well, so they want standability, so they're not sitting out there having down corn. So I think there's there's some guys doing that. I just, you know, looking at the weather going to the fall, I just wonder if there's, you know, if disease starts to come in here next week. Are we gonna see some more late season corn that's gonna get harvested late? Does that call get made? I think that's gonna be, you know, in the next few weeks, we'll see if that what happens there on that side of things.

SPEAKER_02 9:38

Yeah, over here in Ellsworth, we don't have a whole lot of people that go with the two pass system. A lot of times it's kind of a game time decision on what's the pressure out there, how bad is the pressure, and kind of like you said on crop stage, because we don't want to be combining green corn in November. Uh for the most part, uh what we've been seeing has been looking at the weather in in advance. A lot of the disease that I've seen pop up right now seems to do a lot better in the hotter temperatures. And looking ahead here, we're gonna have a lot more colder and wetter conditions. And I haven't seen any of that disease really popping up around in this area. Shockingly enough, Southern Rust has popped up here just north of Ellsworth, just hasn't been very widespread. And at this point, we've done a few two-pass fields, but it's mainly been on a case-by-case basis.

Owen Heetland 10:34

The other thing that I didn't really touch on that the two-pass system allows you to do is better control bugs. So if you're in a long-term corn on corn rotation and you've got a bad beetle problem that allows you to spray early for bugs and then spray again later, really stretching out that window of residual because we all know that a beetle will start. You know, I saw some readdies first, second week of July, they'll they'll come out of the ground all the way until probably September, to be honest. And so anything you can do to stretch out and reduce that load of beetles or root worms in the soil for next year is a good thing. So that you know, making that second pass allows you to do that. Um, so some guys will maybe time their fungicide a little bit more on beetle control so they can kind of kill two birds with one stone.

Nicholas Giessman 11:29

Yeah, I think that's gonna definitely be an option if you are throwing a second pass out there or that's gonna drive a second pass. Because I feel like I don't know how all you guys feel when you guys were scouting for this first pass fungicide that we've done in the last three weeks. Not a lot of pressure. So did the flush already happen or is it still coming? I think it's still coming. So I think a lot of guys that are, you know, maybe on the fence on the second pass, you know, that might be the tipping point to say, hey, we're gonna go control some more bugs and then have the fungicide in the tank as well. So I think that's definitely something to keep in mind to look at.

Owen Heetland 11:58

Yeah, I would agree. As we scouted for that first pass fungicide, you know, you saw some beetles, but not very many. But as we've scouted just to see how that fungicide was working and timing for a second pass, the beetle population seems higher now than it was at that point. So that allows you a little more flexibility of when to use your insecticide.

SPEAKER_02 12:19

And I think with going with another second pass, as we kind of mentioned earlier, with how wet it's been, we are starting to see some deficiencies pop up that also allow you an opportunity to throw in a foliar fertilizer if if that benefit you at this at this point, just to kind of get you through the rest of the season without having any of that deficiency showing up for the rest of the year. But I do have a question for you guys because I've noticed the fields that I know had an instinct or an NSERV or a some sort of stabilizer go out on them. Some may have a deficiency popping up on a plant-by-plant basis, but for the most part, they look far more consistent in not having these deficiencies late in the year than the fields that didn't have those stabilizers involved.

Owen Heetland 13:12

Yeah, I I would definitely agree with that. Whether the stabilizer was, you know, spring or fall. I think that the rain happened late enough that it didn't really matter what kind of product you had and when you put it on. Honestly, even side dress, we were just wet enough for long enough that in areas you're starting to uh see it. So I would agree that it seems like the the instinct definitely did a good job of you know combating some of that. Now, as we continue to get rain in August, there's not a lot you can do about it anymore, but I think it really protected it early on and and helped hold on to that nitrogen as long as possible.

Nicholas Giessman 13:50

Yeah, I I would uh second that as well. I think just seeing more consistency, kind of like you said, Nick, it just seems you know, if you had a stabilizer out there, it held on just a little bit better. So having a stabilizer in the tank, you know, whether it was dry 32 in hydrous, you know, whatever product the stabilizer seemed to make stuff just a little bit better, you know, for what we're seeing right now.

Owen Heetland 14:12

I think that also brings up an another good point as far as scouting goes, is you know, as you start to see those deficiencies, or if you see those deficiencies, a lot of them you're you're not gonna fix this year. Uh, and we know that whether it's a zinc or a boron or a potassium. I mean, we can put a foliar in if you're doing a second pass, but that's something to you know note and think about as we move forward into the 27 crop year of what does it look like I'm short in and how do I start to remedy those situations? That's why it's always good to continue to do some tissue sampling towards the end of the year because it will help you determine what you need to do for the next year.

Nicholas Giessman 14:50

I don't think that could have been said any better because I think right now is the time to see where you're at in August, what's out there for your crop to take up, you know, fixing it if you need more sulfur to put that on with your dry fertilizer or spray it on if you use thyle or the plant or whatever you use, it's a lot easier to get it on with those products than it is to try to supplement in season late, trying to pick up something. So knowing what you are deficient in and then taking that information, meeting with your agronomist and making a plan to tweak your fertilizer wrecks or whatever to make sure you kind of can combat that for next year.

SPEAKER_02 15:22

And I'd say it's also it's kind of the perfect time for it because I know a lot of us are hitting the countryside, you know, talking about fertilizer and how we're sitting for this year, getting things bought up. And when you look out in your field, if you can see that deficiency, that's something to keep in mind when we have those discussions for next year. I mean, a lot of times it's easy to just put the year that you had behind you and just do the same thing that you always done the next year, but that's how you end up starving out your ground. So it's very beneficial around this time to be out in your fields looking at if there's any deficiencies popping up or being in communication with your agronomist on what fertility plans they may recommend. And even as we look to get the crop out, once you get that crop out, it's always a great time to soil sample. A lot of the time it ends up saving our customers money because we're not putting out stuff over what doesn't need it.

Nicholas Giessman 16:23

That's all for this week's Crop Talk by AS. Thanks for tuning in. If any of our listeners have questions, feel free to email them to crop talk at innovativeeg.com. Be sure to like, follow, and subscribe so you don't miss next week's update. And if you know a fellow grower who'd value a quick field snapshot, share this episode with them. For more agronomy resources and to connect with your local IAS team, visit Innovative and follow Innovative Egg services on Facebook, Instagram, YouTube, and LinkedIn. We'll catch you next week on Crop Talk.