Strategic Farming: Field Notes

Transcripts are auto-transcribed. If you need more accurate transcripts of an episode for ADA purposes, please contact Anthony Hanson - hans4022@umn.edu.

Anthony Hanson: All right. Well, good morning, everyone welcome to strategic farming field notes.
Anthony Hanson: So again, welcome today. And this podcast is from the University of Minnesota Extension. We're glad you joined us today. this is kind of talking a little bit more about what we're gonna do in, you know, kind of about the end of May, and with hey issues and early cease insects that are coming up. I'm Anthony Hanson, Regional Extension educator. And today we'll also have Bruce Potter, our Ipm specialist.

Anthony Hanson: So we're gonna both be covering a little bit what's going on, especially in the Ipm world of insects today.

Anthony Hanson: So I think with that, Bruce, I'm going to turn it over to you initially for some of the first questions coming up. I know I've been getting asked a lot about what's going on in off Alpha what to get ready for, especially with, I'll fall for evil So this to kind of go get up that here. What have you been hearing about of health issues coming up, or what kind of on your horizon initially, for what you're keeping an eye out for in the fields right now?

Bruce D Potter: Well, basically, it's helpful. We will. We still have. It looks like we've still got adults moving into the field. we've got as of yesterday. A couple of days ago we had a lot of neonat or newly hatched larvae out there some older larvae, maybe by the end of the week we'll have some second in star larvae, but it looks like that, you know, like typical, that that hatch is going to be spread out.

Bruce D Potter: so I think the alpha we will, are the thing people need to be most worried about right now. I did see my Bruce potato leaf hopper of the season so they've made it up here nothing to be too excited about yet, but they've made it up, and then pafs seem to be the the biggest insect out there. But again not anything close to economic threshold. Now.

Anthony Hanson: yeah, before we get me deeper, I should also mention, thanks to our sponsors as well, the Minnesota Soybean Research Royal Council and the Minnesota Corn Research and Motion Councils. they're funding a bit to help support this program, and it's been very generous for that.

Anthony Hanson: So, Bruce, kind of covering those insects a little bit, obviously, I'll feel we will. I think we'll get into in a little bit later here. But how about some did that say like PA, for instance, some folks maybe aren't as familiar with that one other folks. They've seen higher numbers of it sometimes. So what do you kind of keep an eye out for that one in terms of timing? And what it's doing out in the fields.

Bruce D Potter: Well, they they tend to cause the most damage. And it's actually, I think, kind of rare that you have you lost from them in in Minnesota, but tend to be more problems when it's

Bruce D Potter: dry out. you know. Felt was under moisture stress. there's a lot of different thresholds for them. But

Bruce D Potter: you know, back when I was in grad school many, many years ago. you know, one of the thresholds we kind of used was a quarter cup of aphids per sweep. So you can tolerate some pretty high populations out there, and I think you, where we've been getting into trouble lately is is, you know, after we're spring elf Alpha webles that sort of thing or potatoes, potato leap hoppers you gotta really be aware of flaring the pafids.

Bruce D Potter: There's some little bit of concern that there may be some resistance to parthroids with that insect as well. So no good turn
goes. No, no, anyhow. Do trying to do something sometimes lead to unexpected events.

Anthony Hanson: Yeah, I think the pythroid resistance that's a recurring theme. We seem to be dealing with moving over to all helpful to last year. I know I had plenty of reports in West Central Minnesota, and I think you had a few down your area to southwest Minnesota, where folks are saying, you know, it's like they're pyrers just for working for all we've all I didn't quite get enough samples. I could ship off to get that confirmed, but you know we're suspecting that it looks like there's pyrethroid resistance out there. So what options do we have for insecticides with our 5 people that are left? that kind of stand up to you? Or what challenges are we facing there?

Bruce D Potter: Well, I think the the the challenge we're facing is is the, you know, this high, intense self alpha production system. some guys, this is not new with the alpha, we forward. P. But this has been going on for several years, off and on. But some guys not only got on to a cutting schedule, but they got on to a spray schedule. put a lot of insecticides on you know, and sometimes they'd spray. You'd come back multiple times with a pre-recorded sometimes at lower rate. So you know, the the problems aren't unexpected. we've got a few options we've lost, core purify, which is going to hurt. But we've also, you know, we've picked up steward that that's an option Some of the mixes are options. And hopefully, there's some things in the background that that may help us. But but right now we're fairly limited.

Anthony Hanson: Yeah, I'm looking at One of the tables we produced in the past. we will have a new Minnesota crop news coming out this week from the looks of it. But there are past articles that have some of these insect side tables in there. and yeah, without pyrethroids when we're rotating group numbers for insecticides. right now, it's really only 2 main groups that are left. You have some of the organal phosphates. And then that steward product. That's a group 22 between those. it kind of seems like limited options. There are new updates coming out in other parts of the country and they're saying that you should try to rotate between a different group number every 3 years. Well if you have resistance, Python, or a history of failures in your field of recommending. Stay away from those you only have 2 options left. So
what kind of options to growers have in those situations where we're saying we're kind of in dire straits with the insecticides. and you have to try to figure out some way to manage help help. We go up there with limited sex side options.

Bruce D Potter: Well, I think that's why. you know, this whole concept of Ipm and economic thresholds are important and spring, you know every field doesn't need a Lfal, for we will treatment every year that sort of thing. So if you're doing your scouting and and paying attention to. what kind of populations you have out there, not treating insects that you don't need to treat. That's gonna help a little bit limp us through this until till some new things come up. Come along.

Anthony Hanson: Have you heard much about?

Bruce D Potter: How well, planting? Not just pure stands at all, for whether it's or it's a grass or their grasses in there. I've seen some literature saying how that reduce self-helpful evil numbers. Have you heard more about just how much that helps potentially or no, I haven't. I haven't looked at that literature at all. So I would. I would assume it, would, you know, help, if for no other reason, then there's less alfalfa plants per unit area there to support support the labels.

Anthony Hanson: Yeah, I imagine, too, it it's gonna vary. Now, I've had calls for more dairy producers or consultants helping those folks out, and that's you know, high production. They want you oftentimes just pure off Alpha. If it's a beef produces other livestock, they're little less picky. And you know, maybe that's where kind of showing these trans dairy is kind of the challenge right now for those folks, because they're a little more stringent on what they're looking for. I've had other calls to one of the other insecticides I haven't mentioned yet is spinosid, and that one is used up times more by organic growers. I've been getting questions about that as well, too. now, it sounds like it's pretty expensive product, though, too, and you know, maybe variable. I can see on that one. I know. What are your thoughts on that product? Or that's kind of the only potential third option out there that I've been able to see.

Bruce D Potter: Yeah, I haven't. I haven't tested it on elf Alpha, we both, and but it it's more, you know. I'm more familiar with it as a lep adopter and product So I don't know. I mean, it's, you know, there's not a lot of options out there for them. So I think in their case, their best defense is gonna we're gonna have to come up with some better cutting management strategies for them. Yeah, on that note for that last call I had. I think they're saying it's about 35 to $40 an acre is going to cost to try to treat with that.

Anthony Hanson: So that's why it definitely sounds like a challenge for those folks. So with mowing schedules. And we talk about this a lot for all we will if you mow early sometimes before these treatment thresholds, so that can kind of count as your side side treatment sometimes and help you out reduce numbers. how well does that work and kind of when should growers be trying to time that early mowing versus what issues to come up afterwards in terms of, you know, issues with regrowth and the second crop.

Bruce D Potter: Well, I mean, it depends on what you're trying to. You know what you what you're planning to use at Alpha for So if you're a lot of the dairy guys are cutting that stuff early like right now in Southwest Minnesota and Southern Minnesota. Some of that Alpha alpha probably could be cut if you're in a multip. A high number of cuttings per year. and in this case in this year. That's probably a little bit on the early side, because I don't think you're going to impact the Beatles as much as you will, and we will, as much as you will the larvae as far as I can tell, we've still even got weevils moving into the field, laying eggs. That sort of thing. So Then the other side of it is, it's it's trying to find that happy medium, because if you wait too long and you've got too many larvae out there, too many under the wind, Rose, and you end up with problems there. So I think there, I think we probably could do. we probably need some where a little bit more work on on how to Time these things, and especially in the light of potential resistance to insecticides.

Anthony Hanson: And that's a good point. From earlier you mentioned the adults moving to the fields. And those aren't actually what we treat for. We're not really counting those. It's more the larvae and X hatching and some of the DVD models that are out there. They're showing that Eglay should be happening just around now in Central Minnesota. Probably got maybe some larvae catching in Southern Minnesota. So that's kind of a good point that the timing is, you know, kind of just that point where things are starting to show up in the field for larvae at least, that we're looking at but that's kind of the other prong of the question here is, you know, some of these larvae seem like they're hanging around in fields a lot longer in some areas than people are used to, and we've talked about different strains of our we've in the past. Some sounds like they've been in Southern Minnesota for quite a while. Do you want to talk a little bit about What might be happening with those different strings there?

Bruce D Potter: Well, there's 2. There's 2 bio types. So in in Minnesota or in in in the Northern soy areas, anyhow on the Eastern strain and the Western strain they differ in, and when they lay eggs, one only some eggs in the fall, and if you have a mild winter, those eggs will survive the different when they move into the field. That sort of thing. And so that's gonna to, you know. Determine when those weevils are out there relative to first, first and second cutting and if you've got a mix, then it confounds things even more. in the southern part of the State back when I started years ago, I think we're still already per predominantly the the Western strain, and I'm not sure what's going on in in West Central and Central if we've got a mix of them. A lot of those Degree day models were developed with one strain, and and they they don't work well for both.

Anthony Hanson: Yeah, that's one of the caveats we're putting out now, especially with those 3 day models, is just because it was based on just those one for that one biotype there. It's looking like this Western strain. What we say about one to 2 week kind of extended season, that one. It seems like. So it's I've seen some fields where they had damage into July first. I couldn't find evidence of needles out there anymore at that point. But yeah, it's it's definitely an issue where growers are kind of getting surprised by hopefully, we will hear quite a bit. So if folks are looking at both first cutting and second cutting potential issues. What do you think we need to change sites, you know, trying to more if we can. But if you only have one insecticide treatment that you could maybe do in a year. When do you think the most value for that is trying to balance damage from the larvae and trying to protect the crop there.

Bruce D Potter: Well, if it was it, and it's gonna depend year to year. And I think that's where we need to. You know, we need to look at some some data and and maybe do some research here. And that applies to Minnesota. But this year in Southern Minnesota. I would say that, you know, cutting right now would probably be the thing to do. Cutting early would be the thing to do, and then and then, if you had to treat, get on the get on the we will early in second cutting right away. Don't you know the problems. Big problems come in. If we cut the alpha and and leave it in the windro, everything not only helpful we will, but everything curls under the wind row, and by the time you get it off the field it's there's nothing left. So And then in some years or some other areas. You might be better off. even having to treat that first generation and and knock things back there, and and and rather than try to deal with them later on. But again, I'm there's some. I think it's something that you know, we we we need to look at a little harder.

Anthony Hanson: Yeah, I think with that, and just a reminder to folks. You can ask questions either on Alpha or that we're talking about here, or in a little bit. We're talking more about what's going on. Some of our insects out there. otherwise. Have you? seen this kind of how the crops looking for Alpha. So far, any other potential issues. you've been hearing out there in terms of either insects or other agronomic things.

Bruce D Potter: Well, in in this part of the world here, Lamberton, and you know 1 one highway. 14 I will learned again that the Elf Alpha can't stand under water very long and survive but for the most part, where we've had good drainage. It's if the crop looks pretty good. It looks like it came through the winter. Very well, you know, there's a few areas that I had. Some some frost is, or ponding and frost issues. But in general the crop looks pretty good right now.

Anthony Hanson: Yeah, it's it's funny, the difference. Just a couple of hours drive to make here West Central Minnesota. We haven't had that much rain, and we got the pivot starting up on the Lfall for ground there. So I think with that we can move over to one of the other kind of moderating projects that you work with, especially with moth lights. And what's going on there in the spring, especially black cot worm to army word. You've had some pretty high numbers and some traps, haven't you?

Bruce D Potter: Yeah? Well, it's the same same systems that have brought a lot of rain have brought some migrating MOS, and they tend to drop up you know, they got a pretty good pathway out of the south. They can do some long distance movement on low level jets, you know, 1,500 feet up. They actually the army rooms and blackout rooms actually try to migrate, so they'll actually start flying at dusk. They'll pick up these winds and then head north and then get here from Texas, and in a matter of a couple of days. A lot of times, they'll bet drop out on the back end of the thunderstorms. That's why you know a lot of times. You see, both of them associated with in years where you've had a lot of heavy rains and the the pop populations are going to be higher in those areas where where we've had those rains. So unfortunately, this year. we've got some pretty high captures. It doesn't mean that we're gonna have a problem, but we definitely have some good ma's numbers we've had several flights into Minnesota for blackout rooms the earliest we're in Martin and Swift County back in April. We've had subsequent flights here and there, and the most recent. What came in these these rains around the tenth, eleventh to the fifteenth some of these that came in the Central Southwest Central Minnesota area. Some of the sugar beat areas got tip pretty hard. A trap in Renville, on the thirteenth and fifteenth. I think it was had 21 over 2 nights. We consider 8 over 2 nights you know where we start to get a little bit concerned So definitely, we've got a lot of Ms. Coming in and army worms are the same way, I said. I've looked at light traps, black light traps off and on since the late seventies, and I managed to set I think it was May twelfth or set my
personal record for army Worms 193, and one night a lot of the pheromone traps. We don't have the extensive of network with the army worms, but a lot of those pheromone traps have been picking up quite a few MOS off and on all spring long. And the interesting thing I you know it kind of depressing actually is. You know, we have a black light trap in a pheromone trap. They're probably about a hundred yards apart. We were catching 7 in the pheromone trap, and that's when we caught the 193. So I'm not real confident what those pyramid trap numbers mean. But we definitely it looks like we pulled in fold in quite a few insects.

Anthony Hanson: Yeah, I know. I've seen that with some black light traps, too, where you get surprised by what you find in there, but still over a hundred miles compared to 9 and a fair amount trap. That's pretty wide difference. So in these counties that you're getting these high counts and traps. What should growers be out looking for in terms of timing? And you know what crops are actually the priorities here that these

Bruce D Potter: barbie or the larvae might be feeding on out there.
A small cutrooms and and small corn. They've got an extended period of feeding. Those are usually higher. Risk As the corn gets bigger the cut rooms will take less plants as the cut rooms get bigger they don't have as long to feed. But you know, when they come into the area they're looking for specific places to lay eggs. They like soybean residue. They like low lying areas. you know we don't like it underw like might have happened this year. But low lying areas areas that have early season we growth are really attractive to them. So Lamb's quarters is an example. And we've got a lot of that this this year. out there, a lot of really season weeds and and delayed planning. so that's and I think one of the issues we're gonna have this year, that same rain that brought cut worms up and and kind of messed up planning for people that's gonna make scouting a little tough, because we've got some poor emergence and uneven emergence. and guys are gonna have to, you know, if they see leaf beating from the cut worms that's usually their first sign. But if they're seeing leaf beating, you're gonna have to dig around, they'll tend to be at the border between dry and red wet soils determine if it's cut rooms or not you know. Actually, one of the mainstream main causes of stand loss might be agronomous looking for cut rooms out in corn. But

Anthony Hanson: it's an important task. Yeah. 2 questions is one, what kind of time window are we looking at that. We should be out there scouting kind of when will things roughly wrap up in terms when maybe the corn isn't a susceptible and related to that. How are the Bt traits working for these up the doctrines? are they effective? Or are there actually issues with that where it doesn't quite protect as much. We'll take the Bt traits first. If you've got an above drone, a hybrid with above-grown Bt. Rate

Bruce D Potter: traits. You should be protected unless you got a lot of big cut rooms moving over on to corn. They might they might take some plants out before they succumb. army worms. On the other hand, the only trait that has is labeled for control is the vetera trait. there's not a lot of hybrids with that at this time it's increasing. So and corn with bipteria is is more at risk. Army worms are also, you know anything that's grass, the that, unlike the cutrooms, army worms have a pretty white narrow host range. It's grasses and so small greens are also at risk. And when I mentioned the cut rooms coming in army rooms. Look! Look for the densest tallest that grass vegetation they can find. It's one of the things we worry about with. If you've got pretty heavy rye cover crops and you plant corn into that those 1 one feels you have to be watched real carefully and then, as far as when things are going to happen. you know this, these early flights and and these are going to be in all all available in a link that's posted at the end. But the early flights. We're going to start to see cutworms big enough to cut corn. Black cutters big enough to cut corn by the end of May last few days of May or so the degree day models usually over. Predict a little bit. So end of May early June. And these later flights it's going to be later. It's going to be in dimension. And then as as the as these cou couple and start to pupate. Then we're looking at. oh, it's the probably the 20, fifth, 26 to June for these later flights, and then the earlier flights, probably mid mint, you. And so this is all in in the newsletters we put out when when the cutting will start and cutting should finish, and and just people an idea when to to gauge their skeleton.

Anthony Hanson: So you covered a little bit about right cover crops, and I don't know. This is when we got a few calls about last year I had one field out in Eastern Stairs County that I saw were You know, we talk about how true army, weren't they? For the grasses? But they can hit. So I mean, sometimes I actually saw soybean field that was decimated. They It was too late to replant, and what happened was they had a thick rye cover crop and it was. It must have been right around the time when those larvae were just late in stars. Nice big ones. They terminated the right cover crop This is actually going to be part of the topic for next week cover crop termination. And in that process all those larvae had left to eat or soybeans out there. So kind of folks seem to get surprised by that a little bit sometimes. So what should you be specifically and rye the out there looking for if you are planning your termination for that, and you know when to kind of set up an insecticide application and potentially kind of a thick residue with all that right? Cover crop. Yeah, if you're before you terminate, I'd run a sweep net out there. Look for larvae. you know, it takes about

Bruce D Potter: mo just like cutworms. Those last in stars are where most of the feeding happens in the case of army rooms is the sixth in star. But to get to a fifth in star it's at least about 3 weeks after the eggs hatch the it's all it's it's really spread out for army rooms, because the duls will meet multiple times and and lay eggs over probably a week, 10 day period something or around there. But you know, if you if you're gonna terminate that crop, I'd run at least run a sweep that through there and and make sure that you don't have large larvae and look on the ground as well. Make sure you don't have any larvae in there scout it after you terminate just to make sure you don't have any any surprises. you know, these large larvae can pretty well eliminate a field over overnight, and and people are surprised. And we're trying really need to catch. Those are larvae before they're early, before they run out of food and start going over to the neighbors you mentioned the soybeans, and they will attack soybeans. But The good news is that probably like, it's not they. They probably starve to death if they have to just eat soybeans, so they might be able to finish off. But it's they're it's not a good food source for them at all. They might just as easily head to a feel next door if they if they could.

Anthony Hanson: Yeah, I I will admit it was pretty daunting to see, you know, a whole field soybean. There is only a few green plants across the whole thing, so I folks haven't seen major insect damage before. That's one good example. one last question before we wrap things up. Or I might I might have one more, Bruce. first question is, is there a certain time of day we should be scouting for larvae, and then, just to wrap things up. what other insect issues should we keep an eye out for in the coming weeks here.

Bruce D Potter: Well, I think you know both both army rooms and cut room cup rooms, but the adults and the larvae are both nocturnal, at least the larvae larger larva. So if you, if you're out there looking in the evening, or early morning you have a higher chance to towards see them up in a above the ground. I mentioned the the cut worms. Those are going to be below ground most of the time, and and you know the a lot of times go down a roll, but if you see a cut or wilted plant or plant with leaf feeding. If you start pulling the crust up or or digging down to soil moisture levels. That's usually where you find the larvae they're hard to see, but and they tend to curl up. But you know, like I said, most of them are nocturnal, but not everybody wants to be wandering around all night long looking for cut rooms and army rooms fall into badger holes and stuff like that.

Anthony Hanson: Yeah, so about 2 min left here. Any other insects folks keep an eye out for

Bruce D Potter: Well, I think the the big ones in corn are going to be army rooms and corn root rooms, I'm thinking they had a pretty good winter We'll see what what develops but the but the corn root rooms are probably the biggest issue in corn right now. soybean aphids we'll see what happens there, and it's I think they might get her a little bit with late Soya Bean planning respect to with respect to when they hatch and try to move off and buck foreign. But well again, that's something we'll have to see Soybean Galmage. we don't know. The populations have been down in the last couple of years in Minnesota. So that's actually what I'm going to do later on. Today is start. We're starting to look at emergence cages for adult emergence. So I think, and then you'll find it's going to be potato leaf hoppers after we get done with with the weevils.

Anthony Hanson: All right. Well, thank you, Bruce, again for being on, and I'm sure we'll be talking insects quite a bit more throughout the summer. Here, too, and more issues come up there. So again, thank you. Everyone else for attending. Youm, you University of Minnesota extensions. Field notes. again. When you log off there'll be that quick survey. And again we had Bruce Potter on today. He's our Ipm specialists with University medicine extension based out of Lambton and for other folks just glad to have a, you know. Hopefully, you have a good day, and we're glad to have you here with us, and we want to again thank our sponsors, the Minnesota Soybean Research Promotion Council. So again, we'll be next week talking about cover crop termination and weed issues as well. So thank you, everyone, and we'll see you next week. Yep, check those links out if you're if you got questions on scouting and thresholds, on army worms

Bruce D Potter: like that ones.