Field Crops Webinar Series - Field Crops Webinar Insect Management - DiFonzo Tilmon

February 28, 2022

Video Transcript

- [Host] All righty, well, I've got seven o'clock right on the dot. So I think we'll go ahead and get started. I just wanted to thank everybody who has logged on this evening. We have our very own, Dr. Chris Defonzo. She's our field prep entomologist here at MSU, and a guest speaker, Kelley Tilmon. She is an agricultural entomologist at the Ohio State University. And this evening they're going to be diskussing seedcorn maggot and the rise of fall armyworm, as well as talking about the new Insect Management Guide. Briefly, I just wanted to quickly just show this screen, just to let you know that MSU is an affirmative action, equal opportunity employer, and that MSU Extension programs are open to all without regard to race, national origin, and other things as well. - Okay, well, we'll let Kelley, Kelley's gonna drive the slides tonight, and I will ask her questions. So Kelley and I work together a lot. We have a lot of similar pest problems, and we share Asiatic garden beetle, and a lot of other things, too. When we were gonna put this together, we originally were gonna talk about just fall armyworm, which was a surprise at the end of the season. But I also realized we had a surprise at the beginning of the season, which was seedcorn maggots. So we're gonna do both, and I'll sort of interview Kelley because she knows more about these pests than I do. So I've been called to seedcorn maggot issues before, but usually just in vegetables. So on the left side of this screen is a picture, for example, that I took a couple years ago in some cabbage production, some vegetable production, where the grower sadly had a field of potato from the previous year. He had rented it for the current season. And those potatoes, the volunteer potatoes from the previous season were rotting. And it was a perfect situation for seedcorn maggot. So you can see, he actually had skips and had lost plants and had plants without any kind of root system at all. So I'd seen that before. And in soybean, I had typically seen this kind of feeding on the cotyledons that you see on the right-hand side. It's just basically cosmetic injury and it doesn't do much, but I think that Kelley has worked a lot more with this pest in the field actually creating infestations. So Kelley, can you give us some background on what you know about seedcorn maggot, and maybe show us some pictures of drama in Ohio? - [Kelley] Sure, Chris. So we see, not all the time, but not uncommonly either, pretty severe damage in both soybean and corn. And this is an example of where soybean cotyledons, where the part circled down on the left is pretty much a destroyed stem and this plant is not gonna last much longer. And then this circled right here is the culprit. And I'm gonna give you a bigger picture of the culprit here. This is seedcorn maggot, and you can see it's sort of burrowing into a cotyledon. There's another one off here to the side. And there's yet another one burrowing. You can see you the tail of it burrowing deep into this cotyledon on the soybean. And we call them maggots because they are maggots. They are fly larvae. And if you saw the adults in action, you might not think they looked all that different from house flies. - Can I ask-- - Yeah, sure. - [Chris] In Ohio, oh, you unplugged your player video, do you see more seedcorn maggot in corn or in soybean? Is it much rarer in a soybean field? - [Kelley] Really, we see it in both when the conditions are right to encourage it. And even though they have different planting times, we will still see damage in both when the conditions are right. And this little video is gonna give you just, it's like a minute and a half, and it's just gonna give you a little snapshot of what those conditions are. And some nice pictures of the pest to give you an idea what it looks like in action. So seedcorn maggot is mostly attracted to decaying organic matter in the soil. And those are the conditions that really encourage it. And the flies are the adults that look for that rotting matter in the soil. And that's where they lay their eggs. - There they are. - Those are the flies. Those are the adults. Like I said, if you saw it, you just wouldn't think it different than a house fly. And those are the little maggots that hatch from the eggs that they lay in the soils. And you can see, they can really cause some pretty severe stand loss. In the field right behind me, this was one of our trials where we were trying to encourage stand loss, and you can see right behind my back, how much stand loss we had from seedcorn maggot in soybean. And really, the thing that is most important to keep in mind about this situation is, these are the pupae. This is the resting stage between the maggot stage and the fly stage. And here are some images of the stand loss that we can see under high seedcorn maggot pressure, and another nice little shot of a maggot there in action. So the thing to keep in mind about what encourages these situations is, wow, the video just does not want to stop. Ah, okay. Organic matter, as I said, and that is something you're gonna get the most of when you till something into the soil, whether that's a cover crop or if you're disking in a hayfield or alfalfa, or if you are disking in manure. Anytime you're incorporating organic matter into the soil, you're getting that kinda nice rottyness that attracts the female flies to lay the eggs in the soil. So that's really where we see the majority of our seedcorn maggot problems, in fields that have been treated that way. And in fact, when we are doing our trials, when we are trying to get an infestation, we'll take an alfalfa field on our research farm, we'll disk it in, and then we will plant 7 to 10 days later. And it's almost for sure that we're gonna get some seedcorn maggot infestation. - [Chris] And I've heard of other recipes, I guess you would call it, including dog food being spread onto plots, fish meal. There's all kinds of-- - Bone meal, yeah. - [Chris] Yeah, there's all kinds of oddball things that people use. - [Kelley] Dried blood meal that I guess comes from-- - Yeah, I mean, it's a fly. It doesn't necessarily know that that's a cover crop and that's not what it's seeking. It's seeking the decaying stuff, like decaying potatoes and things of that nature. Anything decaying. - [Kelley] Yeah, any kind of organic matter that's decaying is gonna be attractive to them. - Right, right. - And so, we often see this on dairy farms, for example, where people are disking in manure into the soil. So treatment. Actually, we find that insecticidal seed treatments under the right conditions and when used appropriately can work pretty well. This is a trial we did where, and this is in corn, where on the left, we have untreated. And then on the right are corn seeds that were treated with a neonicotinoid seed treatment. - [Chris] So that was completely untreated seed? - [Kelley] Yep, that was on the left, untreated seed, just naked seed. - Yeah. - [Kelley] Actually, I think it had a fungicide on it. - [Chris] Okay. And in that case, when was the field killed or how was the previous crop? Was it sprayed and then tilled in, or was it just tilled in green? And how long ago was that? - [Chris] We just disk it in green, and then plant 7 to 10 days later. - [Chris] Got it. I think I can see some alfalfa or something there that looks like-- - [Kelley] We typically use an alpha field 'cause we have a lot of alfalfa on our research farm and it's easy enough for us to beg an alfalfa field off the farm manager to do one of these trials, but really, any type of cover crop that you might disk in would do the same thing. So that's something to keep in mind if you are incorporating any kind of organic matter into your soil, it's really wise to use an insecticidal seed treatment. But insecticidal seed treatments are not a magic bullet if they're not used correctly. - [Chris] Yeah, so one of the things, traveling around with my agronomist over the last year or so, I recognized that there was a lot of push by the agronomists to plant earlier, and they had a lot of reasons why they were suggesting that. And I'm talking specifically about soybeans now because we've always had seedcorn maggot in corn, but then seeing so much damage in soybeans was kind of unusual. And I've watched, as people have taken this advice to plant earlier and earlier and earlier. So this was a recent publication that the agronomist put out. I forgot how many months ago. And it was the push to plant soybeans earlier. And then on page three, it has a lot about benefits, but then it talks about some risks, and it lists bean leaf beetle and freezing or something. And it doesn't mention at all seedcorn maggot. And yet, this past season for me, they were not numerous, but I received many calls from the southern part of Michigan about seedcorn maggot damage in soybeans and stand loss. And all these people-- - We saw the same thing, Chris, in Ohio and in Indiana, when I was asked to speak at the Indiana CCA Conference in December, they specifically said, look, we had this really weird early season problem with seedcorn maggot that we don't usually see. And why is that? And I'm like, well, how early were people planting? And indeed, they were really pushing the envelope for early planting. So why would that be a problem? That's something people think, okay, I've put my seed treatment down and I'm good now, but you gotta keep in mind, this stuff is just coated onto the seed and it flakes off. And if you put that seed in the ground and it sits there for a long time before germinating, and particularly if it rains, you're gonna lose a lot of that product off of the coat of that seed. And this product works by, when the seed germinates, the product goes into the tissues of the plant and spreads through the tissues of the plant. It's a systemic. And as the plant grows, it carries that product with it. So if you lose the product in the ground when the seeds are sitting there all cold and wet for a couple weeks, then you don't have protection when you need it. - [Chris] Yeah. And we know that not much gets taken up by plants anyway, to begin with, even in the best of times. I think the estimate is between two and 10% of the neonic on a seed is taken up into the seed. - [Kelley] So I think that's maybe what we ran into, people planted early and then it got cold and it got wet, and things didn't germinate, and the seed treatment kind of got washed away. And then we probably had some decay going on of seeds that hadn't quite survived the transition. And we created an attractive habitat without the protection of the seed treatment. - [Chris] So Kelley, I know you inherited some of Ron Hammond's research in slugs and other things. And Ron was one of the only people I knew that worked on seedcorn maggot, actually creating plots. And he sent me once this little wisdom and rating guide where he had tillage of green stuff that was the highest risk, and then residue kinda down there and maybe bare soil, and no till, like no risk. Does that still hold? Does his rating still look good to you? - [Kelley] Yeah, that's pretty much what I would tell people, and definitely with the tillage of the green matter and the manure being at the high end of the spectrum. And in fact, Ron is the one who taught me that trick about how to get a seedcorn maggot population going for a trial, that trick of disking something in and planting 7 to 10 days later. So definitely, Ron did have that wisdom. In fact, he had a lot of wisdom. I have a file that I keep in my desk drawer, says, wise words from Ron. And he's given me a lot of wise bits over the year that I keep in that file. - [Chris] And you can see that that high risk, it's anything green. It could be heavy weed mat coming out of the fall through the winter. It could be the cover crop, but not because it's just a cover crop, just because it's green stuff that is being tiled in. Kelley, how long would you recommend someone to wait? But if they did do tillage, what's the minimum you think? - [Kelley] Hmm, yeah. That's a good question. The later you plant, the better. I would say push it. To really be safe, four weeks, if you can, if you really wanted to be safe. - [Chris] So if you had maybe some seed lots treated, you might plant those a little earlier than, let's say soybean seed which has fungicide, you'd wanna move that, shift that away from that tillage and green? - [Kelley] Yeah, exactly. Having that insecticidal seed treatment. So we're talking products like Poncho, or there's a bunch of them. - Okay. - Kelley and Chris, I actually have a quick question hear from our audience. Why would no-till result in a low or no risk? I thought this would be good to answer right here. - [Kelley] Yeah, so really, it has to be kind of rotting in the soil for those flies to want to lay their eggs in there. And so, plants just kind of gently deteriorating on the surface doesn't really seem to have that same attractiveness of stuff rotting in the soil. - [Chris] Maybe not moist enough? - [Kelley] Maybe it's not moist enough. Maybe it's not, I don't know, rotty enough. I don't know what's going through the flies' little heads, but definitely it seems to be, has to be something going on in the soil that is attracting them. So if you're not putting the stuff down into the soil, it's not as an attractive a situation to them. - [Chris] That's actually a very good question, because another thing in Ron's long wisdom that he sent me, at the very end, he talks about even tillage of bare soil. And what he suspected was maybe there was some CO2 or some kinda cue that would even draw in flies a little bit to bare soil. Although that would be the lowest risk, until you get to no tillage at all. So tillage itself may contribute a little bit just by mixing things up a little bit. - [Kelley] Making the dirt smell good somehow. - [Chris] There's probably always something organic to work in, you know? - [Kelley] There's probably always some residue, right? - [Chris] Yeah, yeah. That's a good question, whoever asked that. Okay, so our first surprise at the beginning of the season was seedcorn maggot, and then we got to the end of the season and I thought, oh, we're all good. And then Kelley called me and said, are you seeing fall armyworm? And I said, no, I'm not seeing that quite yet. So she was being hit by fall armyworm, and finally, I don't know what timeframe that this was. It was late August. I was down working in the Dundee area and I saw this cover crop that had been planted in a potato field after the potatoes had been harvested. And that's not bare ground, that's mowed by the armyworms as they were feeding towards the silos back there. And Kelley, if you hit one more slide, I think I have closeups of starving armyworms on the left. They refuse to eat the stems, but they're eating everything else. And those suckers are about as big as my pinky probably. And you see on the right-hand side, another cover crop, to link this to cover crops, where they are kind of eating on the sudex, the grassy parts of it. And then they're leaving the peas kind of untouched. So they're preferring the grass first, but they will eat other things. But I had nothing like what Kelley experienced, as she will show next. - Oh yeah. And it wasn't just farmers and it wasn't just Ohio. It was really throughout the Midwest, and the people who belly ate the worst of all were not the farmers who were losing income from their fields being destroyed. It was the homeowners whose lawns were getting totally decimated by fall armyworms. So everything, I mean, just for every farmer-in-distress email, I probably got three homeowner-in-distress emails about their lawns. They do prefer grassy plants, but they will eat other things for sure. They really were particularly a problem in forages. We saw a lot of alfalfa fields. Again, as Chris said, this is not bare ground. This was an alfalfa field that just got eaten down. - [Chris] Was that a new seeding or was that an established seeding? - [Kelley] That was, the one on the left was a new seeding. And the one on the right was not. - [Chris] Got it. Wow. - Yeah. And we saw the same thing in other forages. Clover took a hit. They'll also eat each other, Chris, when they get really hungry. They can go cannibal. I learned that when-- - Interesting. - [Kelley] I actually learned a lot about it this summer, 'cause we've never dealt with it on anything like this scale in Ohio before. It's more of a Southern pest, and there are reasons why it happened this year and we'll get into those in a minute. But first, this movie doesn't have any sound. So we're safe on that score. But this was a mower head that one of the county agents sent me little film of this mower head after hay mow. - [Chris] One of your videos did have film, and the person in the film is saying, holy cow, or something. I mean, an entomologist thinks that's cool, but. - [Kelley] Yeah, I had a meeting, I was running a meeting of entomologists the other day on Zoom that had nothing to do with fall armyworm. But I'm like, guys, I have to show you this. - [Chris] So Eric is asking, is turf and hay killed by the feeding that you showed? - [Kelley] Yes, particularly if it's a new planting and it doesn't have a well-established root system and energy reserves under ground to come back from. So really, new seeding, of anything, were hit the hardest. If something's really well-established and it has a good root mass underground and it has some energy reserves, it can come back from that sometimes. Also plants, if you're looking at the type of plant where it dies if the crown gets eaten away, things aren't gonna come back from having the crown destroyed for certain types of plants. - [Chris] Interesting. Well, so I've been at MSE for 25 years, and I've seen true armyworm, armyworm armyworm kinda moves up from the south and we get it in wheat, as you would, maybe a little bit in corn, and that's like a May, June kinda thing, but I've never seen fall armyworm. Maybe an individual fall armyworm, but not an infestation. And that's because it's truly a tropical pest. So the map on the left shows you its distribution, its normal distribution before it moves around in the summer. So right now it would be in South America, Central America and in the southern tip of Florida, and the southern part of Texas. Now, it's been cold in the South the last few weeks. So it's for sure in the tip of Texas and the tip of Florida. In the warmer kind of winters, it can get up into those Gulf states a little bit, but needless to say, it has to move up towards us every year, and it often just doesn't make it. So it's very unusual. Again, the entomologists that had last dealt with such an infestation are either dead or well retired. And so, I'd never seen anything like this. It blew my mind and some of your pictures just were amazing. So what happened this year as opposed to the past 30 years? - [Kelley] Yeah, well it blew our minds too. And I gotta, at this moment, make a big shout out to my colleagues, my entomology colleagues in the Southern US, because as soon as we started getting hammered, I had no idea what to tell people and what the best approaches were. So I sent up the Bat-Signal and I just got all kinds of help from my colleagues in the Southern US who deal with this pest much more regularly. So a big shoutout to those folks. So what happened? Well, they had a really warm, wet spring and early spring down in Texas, Louisiana, Florida. And that allowed the fall armyworm populations to start building up early. The rains that they had early encouraged a lot of early-season weeds, which was nice, rich food for those fall armyworms that were waking up early. So the populations built up heavier than usual in the South and all throughout the summer. They had much higher populations than typical. So then enter August, and we started having some really pronounced weather patterns. Starting at the end of July, we had a big wind event that was, I think, got this whole thing started where we had a prevailing wind pattern that just scooped those fall armyworms up from Texas and dropped them over the Midwest. But it didn't end there, because the week of August 6th and 12th, we had strong prevailing winds that lasted for pretty much a full week that, again, was scooping things up from that Southern region and dropping things over the Midwest. And so, I believe that is when we got our influx of moths. So the caterpillar is the feeding stage, but the moth is the dispersing stage. The moths don't feed, but it's the moths moving into an area that lay the eggs that become the caterpillars that do the feeding. - [Chris] And those winds, those winds look like they were going right over Oklahoma and Arkansas and that northern part of Texas, which is exactly where a lot of the first reports were coming out, right? That they were heavy populations. - [Kelley] Yep. And those winds brought them to us at just the wrong time, but it wasn't just the wind because when those moths started dropping out of the sky over the Midwest, they were met with very warm temperatures. And a few minutes ago, Chris told you that this is a tropical species. They really are heat-loving creatures. So the warmer it is, the more they like it. And we had August temperatures that was ranked among the highest Augusts in the last 126 years. And that was common to Michigan, Ohio, parts of Indiana, much of the Eastern and Northeastern US. And on the right is Ohio. Our temperature, August temperature deviation from the 20-year norm in the orange or in red or something is the more of a departure it is from the average temperature. So when they got here, it was nice and hot. - [Host] We do have a few questions, if you guys don't mind. Let's see, one of 'em is, if we have armyworms this year, are we going to see them again next year and maybe worse? - [Kelley] Well, that is the one good piece of news. They do not over-winter here. As soon as we had our first really hard freezes, they all died. And so, whether we get them again will depend entirely on what we get from the South. And using a crystal ball, I am gonna say that we are probably gonna see this problem more frequently in the years to come than we have up until now. I think it's gonna happen definitely again in my career. I can't tell you how often, but things are changing. Climate's changing. Warm, wet winters and springs in the South, that's gonna become more common. Extreme weather events, that's gonna become more common. Hotter-than-average temperatures where we live, that's gonna become more common, and all of these factors, if they come together right, mean that, I think Chris and I both believe that this is not necessarily just a one-off, and it's not gonna be an every year thing, but it's gonna be something we need to stay vigilant about in a way that we haven't in the past. Would you agree with that, Chris? - [Chris] Yeah, I mean, I think if you, there's been some modeling work done looking at fall armyworm. Part of the reason is because we've given fall armyworm to the rest of the world. It is now in Africa, it's in all parts of Asia. So there's a lot of interest in fall armyworm and what its new range can actually be. And if you look at the long-term climate models based on how we're warming now, it shows that we might be at a point, not that they can necessarily over-winter here, but that they would get here sooner every year, and they would stay longer perhaps. - [Host] Another question is, other than being a pest, what is the difference between fall armyworms and grubs, and what attracts them both in destroying grass at the root? - [Kelley] So they're a different species. They're in different families. Fall armyworms are a type of moth and grubs, like white grubs, like Japanese beetle grubs, and Asiatic garden beetle grubs are the immature beetles. And as it happens, many of those white grub species do like to feed on the roots of grassy plant. But another difference between those two is the grubs are feeding underground on the roots, and the armyworms are feeding on the foliage at the top. Anything else to add, Chris? - [Chris] No, sorry. The janitors were coming by, so I had to give them my trash (laughs). - [Kelley] Okay, you were twitching. I thought you had something to say. Do we have any other questions before I move into a little bit of the biology here? - [Host] I think the last one for fall armyworm was just if they are a serious issue in Mississippi? - Yes. - Okay. - [Chris] Alabama, Mississippi, Florida, Texas. - [Kelley] Arkansas, Florida, Texas, Gulf states, all in there. Yes, for sure. Okay. You need to understand that there is kind of a cutoff in the best time to manage these things. And they have six growth stages. We call them instars. And the first instars are just little tiny guys. And the first, second, and third instars that go up to, say, half-an-inch long are your best target for control for a couple reasons. First of all, they are much easier to kill when they're little. By the time they get big, they just seem to be a lot tougher and harder to knock out. And so, when you get into those fourth instar, fifth, sixth, and by the time you get to the sixth, that's the last instar before they go into their pupil resting stage to turn into a moth. They're about an inch-and-a-half long at that point. And they get progressively harder to kill with insecticides as they get bigger. In fact, I've heard some entomologists say, well, by the time you get to an inch and a half, just don't even bother. Just move on. And the other reason why this matters as a target for control with the little guys is because if you can stop 'em before you get big, you're gonna stop a lot of the feeding damage. And it's really easy to miss the little guys when you're not looking for them. We weren't looking for them. Not a problem in our area. We weren't really aware. We weren't doing any moth trapping, and that's gonna change. I'll talk about that in a little while, but the small ones don't eat much. So you might not notice them, and you might not notice their damage, but here's what happens. They exponentially eat more, the bigger they get. And most of the estimates I've read suggest that they do 75% of their lifetime feeding in that sixth instar. So if you can stop them at one, two, and three, you are stopping the vast majority of the damage they do. Wait just a few days and they become these just tremendous eating machines, these crop Zambonis that are just going through the fields, taking out everything in front of them. - [Chris] But that's pretty common. We're entomologists, so we kinda know that, but I remember working on Colorado potato beetle, and the biggest ones we called pigs because they ate 90% of what the thing's gonna eat during its whole life stage. So that's pretty common with some of these big caterpillars and big beetle larva. It's that last instar oftentimes. And this actual graphic here with the little boxes, that's actually taken out of or repurposed from an original publication on fall armyworm, like in the early 1900s, when they did these kind of feeding studies and realized how much they ate. So these big dudes eat a lot. - [Kelley] Yeah, so we did talk about our crystal ball stuff. And I'm not saying that we're gonna have problems moving forward every year. Not, I don't think it at all, but I do think this is something we're gonna wanna be a little bit more vigilant about than we were definitely up until now. - [Chris] Do you want me to talk about this or you do you wanna talk about it? - Well, it says CDD on it. - Oh, I guess that's me on it. Okay, so we do have a regional trapping network because after we have an infestation of something, everybody wants to do something about it. What can I do? So, one thing you could do is you could trap. Trapping is not very sexy. It's kind of boring, and when you trap, you really have to trap every year, and you have to get through those boring years, because at some point after boring years, there's a big year where trapping really makes a huge difference. So this trapping network that we have is run out of Ontario. They run it for us for free, and Ohio submits data, as does Michigan. Some of the other states don't, but most of the Canadian provinces do. And we trap now for six pests, including fall armyworm. Now, I was neglectful. I myself did not have traps out for fall armyworm, never having suspected it would come up here, but I do trap for western bean and some of these other things. So the beauty of that is that if they are arriving, then we would know that something was happening. And Kelley's to the south of us. So her traps-- - We got it first. - [Chris] Inform us of something, true. And then we can always look even further south now and see what's happening in the South. But if you'd like to participate, you can trap and submit data, or you can just watch the trap catches as they move along. - [Kelley] And we have a network of about, I think we're up to close to 40 traps in Ohio, where we've been trapping for western bean cutworm each year with our-- - Now, do you do armyworm typically, or no? - Well, we are going to now. We did not. And it uses the same kind of traps. And all we have to do is put another kind of pheromone lure up there at the right time. And we don't really have to change up anything we're doing. We just switch out that western bean cutworm lure at the end of July and switch in a fall armyworm lure. And we report those data each week on our corn newsletter in Ohio. And I know Chris, you keep an eye on that. And certainly, if we started seeing some, we'd be letting you guys know. - [Chris] And if you wanna get trapping supplies, there's a supplier right in the middle of Michigan that you can order from, or probably just even drive by and pick it up. And it's Great Lakes IPM. So the green buckets that I show you, they're 8 to $10 a piece, but I have green buckets that are going on almost 20 years old now. I mean, they don't have to be green. The insect doesn't care. So as they lose color, it doesn't matter. As long as the top still fits on, those green buckets can go a really long time, and then you have to buy lures of course, and change those every so many weeks. And I know that Eric that's on does a lot of trapping too, down in his area. - [Kelley] Do you guys have any other questions for us about fall armyworm before we move on to our final little topic? - [Host] Yes, we do. The first one is, will birds eat the worms, like in an alfalfa field? - [Kelley] Yes, they will. In fact, anytime you see a flock of birds intensely interested in a field, it's a really good idea to go over there and see what's attracting them because often when there's some type of pest outbreak, the birds will respond to it. I suspect that bird feeding is not enough to control the problem at a regional level, but if a really big flock fell on a field at the right time and ate a lot of caterpillars, that might be a big help, but I don't think it's something that, I mean, it's catch is catch can, I think. Did you see any of that bird activity, Chris? I sure did. - [Chris] I only saw a couple of fields down there in Dundee, and I didn't see any birds at all, but I may have been there at the wrong time. There might have been turkeys out there. I don't know if turkeys will eat something like this, or maybe just eat seeds. I don't know. But, I mean, I would suspect that there was all kinds of stuff cuing in on that field, especially once the vegetation was gone, those worms were right on the ground. They were very. - Easy pickins, yeah. - [Chris] Yeah, they were very noticeable. - [Kelley] And there are other things that will eat them. For example, ground beetles, which are a type of predatory insect that we often see in particularly no-till and in forage crops, we'll see a lot of ground beetles. Those will eat fall armyworms. In the native range where they live all year round, there are some specialist parasitoid species. So these are insects that are parasitic on the fall armyworms. And I think they do a somewhat decent job of helping keep some of the populations tamped down a little bit in the South, but the catch is, they gotta be there where the fall armyworm is year round, because they're not strong flyers and they can't make the trek north with those fall armyworm moths. So those specialist parasitoids aren't really helpful for us in the northern regions. - [Chris] And the good thing, like Kelley already said, these cannot over-winter. They're tropical. So they can't survive cold temperatures and freezing weather. They are a tropical insect. So I think the good news now is because of that cold front that was in the South, we assume that that line of survival has been pushed as far down as it probably can be in the US. And so, it's gonna take some work for them to work their way back towards us for next year. - [Host] Okay, and then we have another question. Are there any insecticide recommendations for fall armyworm in turf? - [Kelley] Turf? Sadly, I bounced all the turf questions to people who are not me, but I can tell you that in the field crops, the best recommendations are to use a growth inhibitor type of insecticide. Besiege is one example. And if you can get that on there early, that'll help keep them from reaching that Zamboni stage of feeding. - Very good, and then-- - What about a lawn roller? I see that this question came from Ned Burkey, and I would've thought that it would've been very satisfying to roll one's lawn with the armyworms on there. - [Kelley] I bet it would. An interesting point was raised to me when I was talking about this at the Indiana CCCA Conference and I was talking and I showed that mower video and how many caterpillars were in the hay. Well, first of all, a point I should make is, early harvest, if you're in a forage situation, just if at all you can harvest early, that's your best protection. But it was pointed out to me that he had seen problems with the quality of some of the hay that had been harvested with a lot of caterpillars in it. And there was just this sort of caterpillar goo all over the hay and it didn't dry properly. And when it was bailed, it just kinda like got rotty 'cause of all the caterpillar goo in it. And I had never thought about that, but yeah, I can see how that would happen. - [Chris] Huh. Interesting. - [Host] Final question then is, how concerned about fall armyworm should a farmer be who only grows corn and soybeans? - [Kelley] So double-crop soybeans, I think are the bigger risk factor, and that's not something I think you guys really do in Michigan. In some parts of Ohio, we will do a little bit of double-crop soybean. The reason for that being is it's their pest and summer. And if you've got well-established soybean and corn, I don't think you're gonna see as much of an impact as you will on the smaller plants that you would see in a double-cropping situation. They don't seem to prefer soybean. There was some reports of double-crop soybean getting hit. I think it's less of a risk for those folks. I'm talking opinion here, 'cause I have exactly one season of experience with this pest at this point. - [Chris] Well, so there's also two strains. We didn't talk about there's a corn strain and a rice strain. The strain that apparently came up here was the rice strain, which seems to have more affinity, a little bit, for some of the legume side. So the alfalfa and kinda some of the cover crop kind of things and the narrower-seeded weedy kind of grasses as opposed to corn or sorghum. So I kind of agree with you that probably forages might have been cut and were regrowing right as this thing was kind of coming in. And there was a lot of juicy stuff for them to kind of infest in, but I didn't have any calls from standing corn. - Mm-mm, me neither. - Or standing beans. - [Kelley] And we certainly had plenty of corn in the places that were getting hammer in the forages. - [Chris] In fact, the field, that field that I showed that had the (indistinct), that was surrounded by other crops, and that was just really focused in that juicy cover crop kinda thing. - Great, thank you. - Other questions about fall armyworm? - [Host] Nope. - [Kelley] Okay. Well, Chris, I've been doing a lot of talking, so why don't you cover this one? 'Cause this one's your baby. I really gotta give a shout out to Chris. My name might be on the cover along with Chris, but Chris was, like the fall armyworm that does 75% of the work in the sixth instar, Chris was the author who did 90% of the work on this guide. So why don't you tell them-- - [Chris] I was right where that was going, like I'm a sixth instar or something. Yeah, so during COVID, I was kind of like, had a lot of things kinda cut back and for a couple years, more than a couple years, I knew that the insect guide at MSU had to be refurbished in some way. And Kelley and I had talked about it for a couple of years. So I finally sat down with a chapter and worked my way through how to remake this guide so that it wasn't just telling you what to spray, but more, telling you more about the biology and the thresholds and how to scout better. And some of the other ways of controlling pests. I mean, I know that people that are doing weed control, they're mostly about chemistry, but for entomologists and field crops in the north, we're mostly about telling you not to use chemistry. There's a lot of other things that kill insects out there in the north. - [Kelley] We're annoying that way, but there's a reason for it. - [Chris] So we kind of rebuilt the guide from the bottom up. We have six chapters. So as I wrote 'em, sent 'em over to Kelley, Kelley edited them. She really helped with the corn and soybean chapters. And I think we've got it to the point where it's posted, it's been printed and you might have been able to receive a free print copy if you were in Ohio or Michigan at a meeting, but the good thing is this is also a living document. Right before we were gonna go live, Lorsban bit the dust yet again. So we rapidly just pulled it out of the guide, and we can do things like that. We can add a new insecticide, we can take out an insecticide, we can add a pest, like fall armyworm, which we have done since the publication of this guide. So it's posted for free, and I have a Michigan website here, but Kelley has it on her website as well. - [Kelley] Which I foolishly didn't put in a slide, but Ag Insects OSU will get you right there. - [Chris] You can either download the whole thing, or you can download just the one or two chapters that you need. Maybe you don't grow beets and dry beans. Why should you pay for a print copy of that, if you just want soybean and field corn? And we will, now that it's built, it will be much better for us to edit and that sort of thing. - [Kelley] And I doubt we have any Ohio growers on this call, but it is, all the pesticide recommendations are double-checked, that they're good for both Ohio and Michigan, and they're virtually the same, but in the very few instances where they differ, we note that. - Yeah. So Kelley, if you go to the next slide, if you see a pest that you think, hey, I wish that was in there or there's a crop missing. I probably will get to hemp eventually here. If you're in industry and there's a new product coming out and it's actually registered and it needs to go into the guide, here's our contact info. And we would welcome. We can't do this alone. If you see something, see something, say something in the guide so that we can keep it up to date. - [Kelley] Yeah, and things change with pesticides and we try to stay on top, but we're not gonna go through every month to check those labels. So if you happen to know of any label changes that you can alert us about, please do, and we can change those quickly on the online version. - [Host] Quick question for you guys on the Insect Guide. So any updates that are posted, is this just a case where folks just need to keep checking online and make sure that they have the most recent, I guess, information or is there gonna be some sort of, I guess, how will they know that there's been updates to it? - [Kelley] We always put a date on it of when it was most recently updated. So I would suggest before your field season starts and before you're considering what management you're gonna take, just check and see if you've got the most recent. - [Chris] And I can't really conceive of anything that would change now. If it was a super egregious error, like instead of a one-pound rate, it says 100 pounds. There's a typo. That would for sure be something we would be on immediately and have to publicize. But I think for the most part, the small changes are maybe we added a pest, and the next time you get the print guide is fine. You don't necessarily have to be checking every week thinking you're going to be violating a label or something of that nature because you didn't have the most up-to-date copy. - [Kelley] I think our plan is to do a really hard label check at least once a year. - [Chris] Yeah, it takes a lot of, most people that do guides don't actually probably go through the entire label, and then run it through their Department of Ag website, which Kelley and I did. I wanna make sure that those products actually have the registration in the state. And so, everything is registered. And then someone asked, how does fall tillage affect this? And I think that's related to seedcorn maggot. - So fall tillage is gonna be less of a risk than spring tillage because things are gonna kinda have settled out by the time you get to planting season. So really, it's kind of a two-week window when the tillage is gonna be most attractive to those egg-laying flies that bring the maggots in. - So if there was fall tillage for weeds, the decay and the rot is well passed by the time you get the planting. - That is what I think. I have not done experiments on it, but I believe that to be true. Well, thanks very much for having me on today. I really appreciate it, you guys. - Thank you, Kelley, for being here. - Chris and I work a lot together. So when she said, hey, we can do this back and forth thing. I said, that sounds like fun.

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