Cotton Specialists Corner
Extension Cotton Specialists and others from across the U.S. weigh in on a variety of topics that impact cotton producers, consultants, and the industry as a whole.
Cotton Specialists Corner
Cotton Insect Management During Squaring and Bloom
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If you’ve ever looked at a cotton field and thought, “Do I really need to spray again,” this conversation is for you. We sit down with Dr. Jeremy Green (Clemson) and Whitney Crow (Mississippi State) to get real about cotton insect management when the crop is all over the board and the weather is either too wet or too dry.
We start with what cotton looks like right now across their regions, then zoom in on the decision that drives everything else: scouting. We talk about why a consultant’s “shadow” can cost less than one insecticide trip, how economic thresholds keep inputs honest, and how missing one timing can turn into expensive resprays. From squaring into bloom, we sort through the usual suspects like plant bugs, stink bugs, aphids, and spider mites, plus the new complications of resistance and secondary pest flare-ups.
We also dig into tools and tactics growers are asking about: Diamond timing during peak plant bug migration, what ThryvOn can and cannot do, how longer residual products change your spray schedule, and why stink bug decisions should follow boll injury and week-of-bloom risk instead of a fixed calendar. Then we tackle cotton jassid, why it seems tied to blooming cotton, and what late-season surprises could mean for termination timing. If you care about integrated pest management, cotton scouting, insect thresholds, and protecting yield while cutting costs, you’ll get a lot from this one.
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Cold Open And Welcome
SPEAKER_02Well it was do we think they take the call you call me You promised me the moon and then I wish I wasn't born again I can take I can take it I broken Oh I came there without it with you want it I don't ran away from glory but it's still the only life out of the shoe Bill I finally made some money it's the cotton picking cotton grooving loo Welcome to this episode of the Cotton Specialist Corner Podcast.
Meet The Guests And Goals
SPEAKER_01My name is Campan, extension agronomist at the University of Georgia based out of Tifton, and kind of continuing a few of the episodes we've done this year on optimizing inputs. We've got one, a good one today, talking about insect management and entomology. And so with me today are two good entomologists in a cotton belt, two good cotton folks, Dr. Jeremy Green, cotton and soybean entomologist at Clemson University based out of South Carolina, and then Whitney Crow, uh extension entomologist at Mississippi State. Welcome, guys. Glad y'all are here with us. Thanks, Kev. So, first thing I want to do, you know, a lot of times my colleague here at the University of Georgia will remind me that a lot of entomologists would be a good agronomist, but not every agronomist could be an entomologist. And so I wanted to ask you two, as entomologists in your respective states and and your geographies, kind of what the crop looks like right now, what acres are planted, what percent of it's squaring, blooming, and and different considerations for stuff like that. So we'll start with Jeremy and then we'll jump to the mid-south.
Cotton Acres And Crop Stage Snapshot
SPEAKER_00Yeah, it's uh kind of a mixed bag right now with cotton. Um we don't have a lot of acres. Uh we're probably one of the smaller um cotton-producing states in the across the belt, a couple hundred thousand acres of cotton. We got some that's blooming, we got some that's um not even squaring. So we got a we got a buried crop. I think that's probably um typical of a lot of different states right now. And it's we were just talking earlier, Whitney and I, it's it's either too dry or too wet. No in-between. It's not like some of the previous um years we we we just experienced when we got pretty good regular rainfall, you know. It rained like once a week, and you know, we were producing some pretty good yields uh for the last several years. But I I don't know about this year. The corn crop surprisingly looks okay. I think a lot of the early planted stuff maybe got enough rain, but um yeah, we'll just see what uh see what it brings for as far as insects.
SPEAKER_01That's right. So hey, don't don't sell yourself short, man. 200,000 acres, that's that's a lot for some states, all right? So don't don't sell yourself short up there in South Carolina. Wit Whitney, what about you guys over there in the mid-south?
SPEAKER_04Jeremy, we're not in much better shape in our cotton acreage either. So you're saying just a couple hundred thousand. I think we're the last estimate I heard was 275. So, which is a little bit better than last year. We were under 200, I think was the final um report. But again, we're only a couple hundred thousand acres here in Mississippi as well. As far as our reports, I would say, you know, we struggled the same. It's either been too wet or too dry. And it seems like cotton that got planted really early got hit really hard with rips because it was sending that moisture, and then stuff that got planted kind of in between the early and the little bit later is gonna be looks really good. And then you go back to struggling again. So it seems like it's gonna be really variable as far as what the outcome of those acres are gonna be. But I would say where we are now, the majority of the cotton in the state's gonna be starting to flower, if not a couple of weeks into bloom. There might be a couple um areas where there may be even at the tail end of square, but I would say most people at this point are gonna be in the beginning stages to mid stages of bloom.
SPEAKER_01Yeah, and Whitney, if I remember right, last year the dip in acreage in Mississippi was really because of prevent plant, right? It was too wet, people couldn't get in there and put the stuff in. And so this year it seems like it may be a little bit more of, hey, the decision was to do soybeans or corn instead, right?
SPEAKER_04Yeah, no, that's a bit that was a big driver, was just the amount of rain. Once it started in some spots of the state, it didn't really stop. And they did switch to preventative planting. And then I think going into this year, there was a lot of fear around that same thing happening. So I think the trigger in some instances across all crops got pulled a little early. And I think in some places it worked well to their advantage, in other places I think they took a little bit of a hit.
SPEAKER_01Yeah, for sure.
Scouting And Economic Thresholds
SPEAKER_01So, you know, we we can't talk about optimizing inputs or best management practices for insect management without talking about the importance of scouting. You know, to make an educated decision, you've got to know what's out there. And I don't want to belabor that point. I want you guys to do it because y'all are the professionals. So, Wheatney, why don't you start with the importance of scouting over in the Mid South and then we'll throw it over to Jeremy?
SPEAKER_04Yeah, one of the common things that we've talked about consistently in the last couple of years is really trying to minimize our inputs. And we have some best management practices that we can implement outside of scouting. But really the biggest thing that we can do outside of those decisions, you know, once we've started the year, is making sure we're regularly looking at that crop properly, identifying and counting the pest pressure, and then making a decision from there. Because the only, you know, insecticide that's going to be warranted or justified is going to be based off of that economic threshold. And so it's really imperative that we're making the best decisions we can in the hopes of minimizing those inputs and those insecticide applications, as well as increasing those intervals between applications. And really the only way you can effectively do that is to properly scout the plant.
SPEAKER_00Jeremy? Yeah, the the best thing we can put on our cotton crop is the shadow of a consultant, right? Um that's been said many times before. Um and I often say, you know, for the price of what you pay a scout, a consultant to look at your acres, uh, it's about the same as an insecticide spray, right? And if you if you add all your cost up for going across that acre, uh insecticide, fuel, time, it's about the same price as uh your consultant looking at your acre all year long and uh finding problems and um optimally timing insecticide applications. So I think they more than pay for themselves. So it's very important to have a shadow of a consultant on your crop.
SPEAKER_01Yeah, yeah. You know, it I think it's important to mention that because it it's important to have somebody looking so that you don't miss something, but then you can get behind and then you'll you get in a situation where you start having to re-spray multiple times trying to get out of trouble, and uh that's not where you want to be. You know, you you miss something the first time and then you have to re-spray something. The more the most expensive insecticide is one that doesn't work or one you gotta spray twice, you know. So, or any that goes for any input, whether it's herbicide, insecticide, uh, if you have to replant, right, that's that's twice as expensive. So, you know, the a lot of the same principles apply to this on stuff that we've already talked about in some different episodes and stuff like that. But just for those listening and talking about some of the different spectrums that we might deal with uh in different parts of the belt, I did kind of want to start I I know Whitney, you mentioned that a lot of y'all stuff's kind of coming from square into bloom. Uh, we're very similar to Jeremy in Georgia in that I've got stuff that's just starting to square, and then of course we got stuff that's just coming out of the ground too, and then we've got stuff that's at peak bloom, right? So we're all over the board, and I and I feel like it's that way uh for most of the cotton belt. But I did want to start during square, and of course, we could start earlier than that.
Squaring Into Bloom Pest Priorities
SPEAKER_01Whitney already talked about thrips, and so and that's a very important early season pest. You know, it's the only insect pest we do stunt, we recommend a preventive treatment for, right? Any of us, anybody. So um, you know, it starts from the time you put the seed in the ground, but of course, to kind of keep things relevant, we're gonna start with usual suspects at squaring and kind of what we need to be thinking about in terms of managing some of those pests. And and so, Jeremy, we'll start with you and start talking about insect management during squaring up to bloom, and then we'll jump to Whitney.
SPEAKER_00Sure. Well, uh, yeah, I was just at a field this morning and put out flags uh for a couple of aphid trials that I'm gonna put out tomorrow. Um so this this field squaring, it's get close to first bloom. That's one of the insects that starts to show up about that time. It's it's something I don't get real, I don't get real concerned about aphids. I consider them to be food for beneficials for natural enemies for the most part. We've got the fungus that comes in and takes them out, but uh and uh not other natural enemies, and then they kind of just disappear, and then we have a lot of predators out there. So um, but aphids are in that mix. In South Carolina, about I don't know, one out of 10, one out of 20 fields uh has uh legitimate problems with uh problem with plant bugs. Uh so we're not like the mid-south where it could be um you know every field, it's just a matter of when they're gonna be a problem in that field. Uh for us here in South Carolina, plant bugs are a sporadic pest, something we really got to have that shadow of the consultant in the field to figure out if that's that's a problem field or not. And then we kind of transition into um stink bugs is our number one insect pest complex of cotton here in South Carolina and much of the southeast. And then we'll throw in this cotton jacid uh that apparently is just showing up in fields that are blooming in the southeast. So we haven't found any any cotton jacks that show up in pre-bloom cotton, and that's kind of kind of what we saw last year, too. Uh we were we were pretty much right at bloom in first couple weeks of bloom when we found them last year. So we've got that whole mix of uh of different um bugs to look at as we kind of transition from squaring into flowering.
SPEAKER_01Yeah, so you you mentioned aphids on on some of the squaring cotton, and and I'm just curious, I I know what Philip would say, but you ever recommend a field get sprayed for aphids or you're not 100% sure on something like that? Like what like you say, it's really just food for benefit. They're there, right? Until they get wiped out.
SPEAKER_00Yeah, there are some circumstances where you probably need to alleviate the stress of aphids on a on a cott crop. You know, if it's a young cotton crop, let's say it's it's stressed, drought stress, and you know, and and you've been you've been sitting there for a week or two with heavy populations of aphids, you know, maybe there's a maybe there's a good a good reason to control the aphids there. But I've seen countless times where we get to that point, they spray, and then the aphid fungus shows up and wipes them out within a matter of days. And if you just waited like two more days, you would have got free control and not have not had to pay for that aphid spray. So uh and I've looked at a lot of data sets where we've looked at yields uh in the mid-south and the southeast, and it almost never pays to spray aphids, almost never. Yeah.
SPEAKER_01Yeah, we we only talk about it around here if it's you know, dry land, sucked down, like wilted crop, you know, real re you really gotta be in a bad spot to spray some aphids. And you know, a lot of times you try to go with something cheap if you can. Um, but you know, it's not you gotta keep aphids in mind if you do have to make a plant bug spray, right? Or else you can put yourself in a worse situation.
SPEAKER_00So and this cut through this cotton jacid then. So if you're trying to scout for cotton jacid and you got aphids out there, you can't see them. Yeah. Maybe you need to spray the aphids so you can see the jacets or spray material that will control both. So it gets complicated with the new invasive species.
SPEAKER_01Yeah, for sure.
Plant Bugs In The Mid-South Reality
SPEAKER_01Whitney, what about you? I I know that in the in the mid-south, plant bugs are king, right? And so especially on on squaring cotton, but you know, kind of what are some best management practices during during squaring in terms of insect management for you guys?
SPEAKER_04Yeah, so our predominant issue, I mean, is plant bugs and you know, has been for a long time. Not to say that we don't occasionally have aphids. There's been a lot of conversation lately with aphids and spider mites because it's been hot and dry. In a lot of the state where we spray a lot of plant bugs, there's a lot of transform going out. So that really kind of controls the aphid component of it. But when we're talking about just squaring cotton as we start having adult migration, really the goal is to stay away from like the achates or organophosphates in the hopes that we don't flare spider mites. Because oftentimes that's where we see it start. But we have some pockets in the state that have really bad spider mites, and it's been hot and dry recently. I actually had a phone call a while ago trying to figure out what to do because he had plant bugs, spider mites, and aphids. And so, you know, we're talking about through a a couple of scenario scenarios on what to do. But yeah, most of what we're dealing with is plant bugs, occasional spider mites, and then aphids maybe hit or miss. And and plant bugs are an issue starting in at square all the way through the end of the season. And then towards the end of the season, you know, occasionally we still talk about bullworms, but with the implementation of three gene cotton, it's really not an issue, but people are still scouting for them.
SPEAKER_01Yeah. So, you know, looking at at plant bugs and spider mites, it, you know, around here, we kind of assume that's the that's the cost of doing business sometimes when you spray plant bugs. But over there, Whitney, unless I'm mistaken, y'all have got some resistance in spider mites. Is that correct?
SPEAKER_04Yeah, resistance in spider mites and plant bugs. You know, a lot of what we're using for plant bugs transform, not so much, but with um, you know, acate bifanthrin, there's some level of resistance. And as we increase in the in throughout the season and spray more, we see that that efficacy oftentimes starts declining for the spider mites, you know, in a lot of areas there's agrimec um resistance. Now there's some overwintering fitness cost penalty, something that happens because sometimes we can come back the following season and maybe get one application out where we can get C O K control with the agrimec. But there's parts of the Mississippi Delta that they don't even acknowledge, you know, using that product because they don't see consistent control with it. So they're automatically going out with a Zill type product just because that's what they're gonna get the best control with. You know, now that we have Rtento, that really opens up for areas that have really bad spider mites and plant bugs. It really helps us be able to target that situation with one product instead of having to tank mix multiple products. So obviously, you know, if we can prevent flaring secondary pests, that's ideal if we're starting an adult migration real early. Other things we recommend as far as best management practices is in the delta where we have really heavy pressure. Oftentimes we can see a decrease or an increase in efficacy if we make a sequential application application within four to five days. That really helps in those real, real high populations where you don't have a lot of options to rotate. I would say the hills of Mississippi is going to be more comparable to like Alabama or the Southeast. They're not spraying quite as much. And so they can scout and generally spray once or twice for plant bugs.
SPEAKER_01So for so for the Delta where it's a more consistent issue, is more of a calendar type spray, or they they still, you know, get the beat sheets out and all that good stuff.
SPEAKER_04They're they're still scouting and they know when they start getting that heavy pressure, because we're getting a lot of phone calls right now that adult migration has been bad. And if you have any cotton blocks next to corn or really any other, you know, ditches full of weeds, whatever, they oftentimes increase that edge effect. And so with more corn in some areas, there's a lot of people that just are having a heavy adult migration, and so they're constantly in there checking, finding plant bugs even after applications. And so in those in those situations, it's probably beneficial to make that shortened interval application. But yeah, it's it's still ba based on insect numbers. We're not recommending spraying when you don't, you know, aren't still scouting. Right. It's just a lot of times, even our really effective products on a in a good week, outside of Retento in a good week in the Delta. If you get if you get seven to ten days, you're doing really well. I would say most of these applications are going out probably even shorter than that in some instances with really, really high pressure.
SPEAKER_00Yeah. Y'all still use a lot of diamond, Whitney?
SPEAKER_04Yes, still use a lot of diamond. We recommend, I can mention that too. We recommend a peak adult migration. So that could be third week of square, first week of bloom. Huge benefit to that application. We generally see, you know, the original data was just that one single application got about a 200-pound increase from not using diamond. There's a lot of people in the Delta that are using diamond um in multiple intervals. So then at that peak, migration, and then they'll usually throw it in a little bit later as well. So that's a big per a big part of plant bug management in the mid-south is diamond.
Diamond And ThriveOn In Programs
SPEAKER_01So what about the fit in a in a plant bug program for thrive on technology, right? We in the in the lower southeast at least, I don't know about for you, Jeremy, but the the varieties are getting there, they're close, but they're they're not the best things that we're planting right now. But I know that the the effort's kind of been targeted towards that mid-south geography because they have the big problem with plant bugs. And so where where do you see a fit for for thrive on? And and I mean, really, right now I'm kind of curious how many, what percent of the acres do you think are planted to thrive on?
SPEAKER_00Oh, that's a good question. Uh, I don't have a good handle on that, but as you mentioned, the the varieties are getting better that contain the thrive on gene, uh that trait. Uh, and as they get better, we'll see higher adoption because we do get the benefit of um helping with thrips. And certainly in uh in an environment where we don't have plant bugs in every field or in sporadic fields, uh the thrive on trait's gonna help us there. Uh it's gonna help take that plant bug pretty much out of the picture for us in the southeast, yeah, uh for the most part. But uh yeah, we get to get a great benefit on thrips, um, and then also uh helping us with uh plant bugs. They just get a little better, they yield a little more, uh, there'll be more adoption. Yeah. What about you, Whitney?
SPEAKER_04So we see the same thing. The varieties are not where they need to be. They prefer there's some Bull Guard three that they prefer. And so they're gonna keep going with those for the time being until they see that these thrive on varieties are equivalent. And they and we've made uh I think significant progress in the last couple of years. But at least in the mid-south, and I don't know about the southeast, once these guys decide what they like, they're gonna use that till it's no longer an option. Like I think if you gave them 1646, they would go back to using 1646. Like they loved it, they wanted to keep it. So I foresee that happening kind of with ThriBon. Our adoption is really only about 25%. It's still pretty low. But again, as that yield potential starts changing, you know, we're very limited with our tools on plant bug management. I do we will see that shift, and we're continuing to see that shift. They're becoming more comfortable with that technology. But I think in the Mid South, there's still some work to do around how we decrease those applications to really get the true benefit of that technology and minimize some of those inputs.
SPEAKER_01Yeah. We're seeing a little bit more around here in Georgia. We got two problem areas in the state that that deal with plant bugs regularly and adoption's going up there just because they see the benefit in terms of management and and two, you know, you mentioned that shortened application interval. A lot of a lot of guys around here, you know, in Georgia, and I know in South Carolina, it's probably a similar story, Jeremy. You we're set up to hit a field every two weeks. And when you're set up that way, you can't just go in five days and do it again, right? You you can't cut loose. And so that thrive on is kind of like insurance for those guys, right? But in the places in far southwest Georgia and even Dooley County where we deal with plant bugs pretty regularly, it it's it's gaining a little bit of traction. And and and I mean, I think we're close on on some of those varieties. And so we're we're certainly getting there. We're evaluating more and more every year on farm and trying to get an idea of where they fit and and stuff like that.
SPEAKER_04So the best thing with that technology is that it buys time. I mean, that's single handedly, it buys time, and I think it buys us more time than I think we even realize some. times.
SPEAKER_03Yeah.
SPEAKER_04Just because those plant books can hang out a little bit and that plant's pretty tolerant.
SPEAKER_01Does it buy more time than like if you were going to plant a B3XF or or a or a wide strike in list variety or accent flex or whatever, a non-throthant variety, uh, would it buy you more time than a diamond application? Or would you say those are equivalent? That's a good question.
SPEAKER_04That is a good question. I'm not sure.
SPEAKER_01Hey, there's an idea.
SPEAKER_04Yeah, I don't know. I don't know if it buys you more time per se. I think it's just different. Right. Because the urgency isn't there, right? With the thrombon, whereas with the diamond, we're going to get what we need. It's going to hang out in the field for a while, but it needs to be there and work. You know, it's going to take a minute for it to work, right? So I would say the more initial recoverability and time crunch. So like when we have a bad weather event and we can't get in the field and spray, which a lot of our acres are sprayed with the airplane, but you think ground rig, whatever, it buys you time in that one moment, whereas the diamond times are going to have to be a little bit more pre-planned.
SPEAKER_01I get what you're saying. I get so it it'll help you if you get in a tight kind of thing.
SPEAKER_04Yeah. When you're in a crunch and the environment is against you, that technology is going to buy you time until you can get back to that field. Or in your case, you know, you're saying it'll be two weeks before we make our circle back to that field. It's buying you that kind of time, right? Like time to move equipment, logistical time that we can't control.
SPEAKER_01Right. Yeah, because it I you're going to have to reapply diamond at some point.
SPEAKER_04You're going to have to already have it there, right? For it to help you out.
SPEAKER_01Okay. Yeah, I get what you're saying.
SPEAKER_04So but that is a good question.
SPEAKER_01Hey, there's a there's a graduate student project in there somewhere. There's an idea. So all right.
Stink Bugs And Boll Injury Thresholds
SPEAKER_01So kind of moving, you know, we we've already kind of hinted at some stuff during bloom, but here in the Southeast we do not have a severe plant bug issue like they do in the mid-south. We deal with some other stuff. And uh Jerry Jeremy mentioned stink bugs. So Jeremy let's talk about stink bugs a little bit, how they're scouted for, what we need to be looking for, maybe that dynamic threshold and and different stuff like that. And you know it before you get started, it's kind of interesting to me. I started thinking about this this morning. Dr. Roberts told me I have I've never experienced a bad stink bug year. And so it's you know I've never seen them just like clean your clock so to speak. And so but I I think in a lot of situations people who've gotten used to spraying for stink bugs at the third week of bloom and the fifth week of bloom and maybe aren't looking. And I think that that could be a potential savings for these guys. And I and I know that if they're spraying bifenthrin or whatever, right, that's cheap. Right. It's not it's not saving the product but if you save a trip across the field that's a different story, right? So let's talk a little bit about stink bugs and uh kind of what it looks like around here in terms of managing that pest.
SPEAKER_00Well well thankfully you mentioned uh bad stink bug years. Thankfully usually our bad bug years are rainy years and they're good yielding years. They're they're years where we make a lot of cotton. Yeah. So as the conditions are good for the crops, the conditions are good for the bugs too. They they do well. They do not do well when it's dry and hot like it is right now. You know insect eggs are are are susceptible to desiccation and they dry out and we just don't see a lot of uh reproduction when the conditions are worse. But um but yeah thankfully the the yield tends to be higher when we have bad bug ears. We were talking about thrive on I wish we got some help with thrive on on stink bugs but there is zero help thry on on stink bugs. It helps a lot on plant bugs but it's zero on stink bugs. So so we have to get out and we have to look um yeah if you rely exclusively on the calendar sprays or the the crop phonology sprays at the by week of bloom uh you may be spraying when you don't need to spray maybe you need to spray the third and the seventh week of bloom. Yeah not the fifth uh or if you spray the third and the fifth maybe you needed to spray on the seventh but you didn't know because you didn't have a consultant you were just going on a calendar and then when a new insecticide like this vertento has a very long residual and then that complicates things also uh we're used to spraying the the cheek bifenterin and you get two weeks before you got to hit it again. You might not have to hit it in two weeks with this vertento. It might give you three weeks. So so yeah this uh dynamic bowl injury threshold that we worked on for a long time uh we had a static bowling bowl injury threshold uh from some of my PhD work and um postdoc work and then we revised that and and changed it and and the whole the whole premise behind that is that um you have a the largest population of bowls that are susceptible to stink bugs are during that third fourth and fifth week of bloom so that's where it's kind of more critical because you have more bowls that are susceptible to injury during that period. So anyhow the the threshold uh changes by week of bloom um you got to pull bowls you got to pop up in bowls and look look inside to figure that out that does take time but I think our consultants over the decades have gotten used to doing that um and uh and that will prevent you from spraying when you don't need to spray or it'll tell you to spray when you weren't planning on spraying. So yeah again you need the consultant to to look and like I said especially with these new products that are going to give us a lot of residual and they're gonna cost more uh you really need to put them out at the right time.
SPEAKER_01Yeah. Oh gosh yeah um so you know it's funny you bring up doing it based on the calendar of the crop phonology. That's normally what we do on the experiment station just because it's easy and we kind of know like hey you can keep people out of the fields a third week bloom or whatever. But last year I actually had some of my graduate students scout all of our stuff on experiment station and it was fascinating to me that he was scouting some fields some earlier planted stuff like April uh 15th planted and scouted and scouted and scouted and sprayed plant bugs once which I never would have done Whitney like that's just we just don't do that around here. And then we didn't spray stink bugs until the seventh week of bloom. And so it was you know it's crazy like when you're actually looking it's like you can save a lot of money that way but it I would have never known to spray plant bugs in those fields and then I probably would have made two additional insecticide applications for stink bugs when I didn't need to. You know so I mean that that to me illustrates the importance of scouting is we could have lost on the front end from plant bugs, but we saved on the back end by cutting those two stink bug sprays. Right. So um Whitney I know that plant bugs are still king and during bloom but does management change at all once you move from squaring to bloom and and then two another kind of an additional question I hear you guys talk about the word embedded like they get in there you know and they don't it's hard to get down to them. Does that only happen at bloom or does it happen during squaring too or what's you know what's kind of the thought process during bloom and is it different than it is during squaring?
SPEAKER_04Yeah so the only thing that changes from squaring to bloom is the threshold's going to change and we recommend during the squaring period and some people do it longer, but we recommend you look for adults as well as well as evaluate square retention. So you want to stay above 80% square retention during that squaring period. Because a lot of times what'll happen is is we're making applications that allow us to retain fruit but as you have continuous adults coming in it doesn't look like you're getting control per se with products that aren't going to stay in the field very long. And so as long as we're maintaining above 80% square retention and don't have you know tons of adult plant bugs, we're generally not concerned. Whereas once we start moving into uh flowering cotton we start looking more at at nymphs that's gonna be the bigger concern and generally the main focus and so once we start, you know, there's some things that can be done outside of insect management you know we had mentioned this before and some of it's already we were past, right? Like early maturing varieties, planting date, those things really impact our ability to reduce our inputs but things that we can do in season and again probably done for most of Mississippi but choosing an optimal nitrogen rate and making sure that you have optimal PICs management. So by preventing rank cotton so if we're minimizing you know using the the low end of our nitrogen it helps prevent rank cotton and then as as well as making sure we have the right management strategy for that particular variety whether it's you know more aggressive and you're using more PICS or vice versa so that we can keep that plant a little bit lower. So when we don't have rank cotton it does make it easier to manage plant bugs because that's what they prefer. And so that does also help us in addition to you know proper insect insecticide choices, rotation, that sort of thing and then you know we don't have stink bug issues not to say that there aren't some areas where they are the one thing I do fear as we see an increase of thrive on adoption over time, how will that change the landscape and the insect dynamics? And we potentially could see more stink bugs coming into the Mid South that we're not historically dealing with. And that's the one nice thing you know Jeremy mentioned it was Vertento. And so we can place that you know well in a thrive on system if we start seeing stink bugs, you know, since it does have active BD both on plant bugs and stink bugs. You know hopefully that's a down the future issue, you know, cotton jazz it on the horizon. We don't need to be adding any more you know potential products to uh these tank mixes because that's the issue we're starting to run into is we can control a lot of these things, but they're not all controlled by the same products and that'll be an issue we'll probably continue to face at the pest dynamics keep changing.
SPEAKER_01Yeah you know I was I was gonna ask so you talked about during squaring you you try to use some of those softer chemistries save some of the harsher stuff for during bloom I I was going to ask do you think you're covering up the stink bugs or do you think they're just not there?
SPEAKER_04They're just not there because we're spraying plant bugs so frequently with like acate bifenterin that we're we're keeping those stink bugs knocked back because we see stink bugs in soybeans predominantly um now granted if we get planted early we don't oftentimes have to spray it but we have stink bugs in the state it's just where there's plant bugs they're getting sprayed so frequently that stink bugs just generally aren't an issue.
SPEAKER_00Right.
Cotton Jassid And What Changes Next
SPEAKER_01So with control yeah right um so Jeremy you brought up Jassid we did a uh episode on Jassid back in I think it was December or November maybe but um you know kind kind of what are some of the things that you're thinking about right now as we're in you know for you talking about the crops all over the board some of it's squaring some of it's blooming what what are you thinking about right now um with respect to managing insects and and potentially preventing you know a problem with jasid down the line well so uh so so we have learned that this insect cannot take the winter here right so uh you know it it it doesn't it doesn't look like it it successfully overwinters in in much of the southeast it's a tropical insect so it can handle the summers but it can't handle the winters here.
SPEAKER_00Uh so we're looking at migr migration now we're looking at these insects coming in and with the only detections uh being in blooming cottons we can assume that there are some floral cues that are pulling these these bugs as they migrate into the the areas into the states to pull them in into cotton okra you know crops that the that they um do well on uh so those floral cues uh and then we talk about you know the all the the insects that we normally deal with you know plant bugs stink bugs and in the blooming period it looks like we may add this insect to the uh to that again this year and then have to manage them at the same time that we're managing our you know existing pest that we deal with you know every year and and that's a challenge um you know some products work on everything and then some products are very specific they only kill one you know we just pick just pick one of these insecticides that worked well on uh cotton jacet last year like carbine yeah we get very little on stink bugs with that with that insecticide but it's great on cotton jacet um you know plant bugs I can't remember Whitney is carbine okay is it like a four or five out of ten not even that high it's a different ligus species they spray it for in Arizona I think yeah it's not great yeah yeah so so we have uh a lot of selectivity with insecticides and then some are are more uh broad spectrum but um yeah we got to fit cotton jazz it into these um these different systems and it and it's gonna be totally different if they if they move into the mid-south than it is here and you know we'll just have to figure figure out how to how to control that pest.
SPEAKER_01Yeah yeah and learning learning to live with it you know it's uh it is interesting that uh I believe Jeremy it was a year ago this week that you found it in South Carolina right it was today it was the 7th of July.
SPEAKER_00Yeah so my crew's in the lab right now looking at samples so I wouldn't be surprised if they say we found one.
SPEAKER_01Hey if they come in during this podcast you just say hey we got it so you you just stop and we'll we'll make the announcement uh on the podcast but um you know it is interesting that you brought up the bloomin' cotton thing I you know I I try to convince my colleague here that I know what I'm talking about sometimes and last year we we were spraying a lot of the stuff that was further along you know and uh I made some trips across fields that that were 10% open 20% open and I had been there the week before and it had just started cutting out and I you know I said man there's something to this bloom this blooming or like bowls opening or something like there's you know I I don't know enough about it plant volatiles or whatever like something obviously changes in the plant and and I think there's still a lot to learn on whether you know they came in deering squaring and dumped eggs and then it got to a point where we could finally find them at bloom or if they're moving in at bloom from wherever they are. Because we the hard part is we like nobody could find them in the wintertime. So it's like we we don't really know right now today uh where exactly they're coming from but for some reason it does seem like they're attracted to blooming cotton or blooming okra or whatever it is.
SPEAKER_00Right. Well I put out a trial last year in cotton and it it was at the seventh week of blue when I put the test out. Yeah. So it had been blooming for weeks and and it will kind of backtrack and I think they probably came in you know first week or two of bloom into that field. And it was the earliest planted field that the grower had and a lot of his other fields didn't have issues with cotton chassis. So they found this field, this flowering field before they found everywhere else and they kind of settled in that field. So yeah I think there is something to the flowering uh floral cues that are probably pulling this thing into into cotton we may not deal with it before bloom in cotton that'd be great. Who knows yeah that would be fantastic I would prefer that actually we can actually handle it if we if we get them at at bloom and not on seedling cotton. We don't want that. Nope. And that's probably a that's probably a good bet if you were going to bet on that that's probably a good bet that we won't see them before bloom. But I think we can handle them. We've we've got we've got some insecticides and I think we can we can do the job.
SPEAKER_01Well and it's like I told I tell people that even if it was all the same if this year was the exact same as last year I think we're gonna be in a better position this year because logistically we're in a better position, right? Products here, you know we know what we're looking for like we we know how to hand we learned how to handle it last year. And so this year we're in a better spot even if things were the same, which I think that this year is going to be a little bit different, but we got a long way to go, you know.
SPEAKER_00Yeah. And and one more thing uh I know you mentioned it probably back in December when you guys talked about it but uh the simple things like the hairiness of the leaves yeah uh is is is is quite variable even though we have mostly smooth cotton varieties there is some variation and the differences are pretty dramatic yeah on on what this how this thing what it prefers and it likes the smooth leaf stuff and that's pretty much what we have. Yeah um but you know a lot of field to field differences are probably due to something like that.
SPEAKER_01Yeah yeah for sure and you know that complicates things for us they like smooth cotton but white flies like hairy cotton right so it complicates things down here in in Georgia for us but luckily luckily not everybody has that problem so we'll just keep that one here.
SPEAKER_04So um Whitney y'all did find Jason last year right we did we found it mid-September and we ultimately ended up finding it first in more like central Mississippi and then found it in um along 82 both on both the east and west side of the state so it was pretty it was probably in more places than we're even aware of but it didn't show up until September. At this point we've not found it I haven't had any um calls about it as far as people find it nor have we found it looking for it in the state so I'm optimistic if everything's trending like it was last year I'm optimistic that hopefully we don't find it until much later but again we don't there's a lot we still don't know so we'll be monitoring for the next couple of months trying to see if we see it and in what kind of population. Fortunately, you know like Jeremy was saying we do have products that do control it. It'll kind of be a shift from our main plant bug products that we're currently using. But thankfully the Mid South sprays frequently enough that the concern probably of more applications is already kind of in their minds. My biggest fear is the fact that it's a problem so much later that oftentimes it's passed really when we're done scouting and a lot of times past insecticide recommendation. And so if it does show up late, are we going to have to continue to scout and spray later than what we currently are that's where my biggest fear lies right now.
SPEAKER_01Yeah.
SPEAKER_04But like you said there's just so much we don't know.
When To Stop Spraying Insects
SPEAKER_01Yeah yeah yeah that brings up a good point and something I hadn't thought about with during this conversation is when do y'all typically terminate insecticide applications in the in the Delta?
SPEAKER_04So we're our recommendation our official recommendation is note above white flower five plus three hundred and fifty heat units a lot of people aren't tracking heat units and we've tried to do it based off a note above white flower but you know there's varietal differences but most of the time if you have a white flower blooming out the top of the plant that's really about equivalent to insecticide termination. So that's really where most people fall and I would say there's probably a lot of people that are still scouting well past what they should be. And sometimes you know that's where the bullworm issues come in because we're seeing a dip in that expression and if we would have just walked away from it we wouldn't have been concerned about what we didn't know. But um but yeah so based off of some of the things we're hearing you know they could Jazzy could be still be an issue past that period.
SPEAKER_01Yeah. Jeremy when when do you typically recommend somebody walk away from an insect standpoint?
SPEAKER_00Yeah well the the last insect uh that we're dealing with the stink bugs you know the stink bug complex and um you know if the bowl injury threshold is followed um that increases by week of bloom and if you're under threshold through the seventh week of bloom you're pretty much out of the woods at that point. But that doesn't account for white flies and and other things that may be an issue out there maybe spider mites or something at the end of the season that that might rob a few pounds here or there. But yeah the seventh eight eighth week of bloom you're pretty much good to go. Yeah.
SPEAKER_01Yeah that's generally what we see I've been in a battle with white flies before that's been later and and of course we did some Jassid stuff last year that was after that but you know
Application Coverage Droplets And Speed
SPEAKER_01typically once you get out of stink bug time you're you're in the clear around here right so um you know and one one thing I wanted to discuss there's so much talk around sprayer application parameters especially uh when it comes to weed control I thought it'd be worth talking about because we did a weed control episode and a lot of it was about optimizing applications of Liberty which actually probably goes well with this conversation in terms of increasing the amount of water, finer droplets, um spraying during the daytime You know, stuff higher pressure potentially could do uh better with Liberty. But, you know, a lot of folks are spraying these oxen herbicides, which require larger droplets, um, 15 gallons or 10 gallons to the acre. You know, you don't want a ton of pressure because that creates all those fines, and those have a higher likelihood of moving somewhere that you don't want them to be. So, what do you guys typically talk about with respect to uh sprayer application parameters with respect to a successful insect application?
SPEAKER_00I go first. The um we have actually looked at droplet size uh impacts on uh thrips. And to boil it all down to one statement, it didn't matter. Yeah. As long as we were spraying asophate at at some droplet size, uh, we got control. Now that's that's on an open canopy, right? Really small plant seedling, so kind of makes sense. If you got more of a canopy there, you know, it's up to your chin, you can't get the insecticide down low, then of course you're gonna have um, you know, control problems. You're just not getting the material down where the insects are. I'm sure they see this in the mid-south. We've tried some of the sensitive paper, water sensitive paper, and done some of that work, and um and it does matter as the canopy gets a little bigger for sure. Uh here I will tell you this. We we actually did some work, uh, and it was hard to test where we had we had droplets and we had no droplets. So we sprayed strips in in a field. You know, one pass, skip a pass, spray a pass, skip a pass. And that works well for stink bugs initially because the adults move around a lot and they'll move to the treated strip and to an untreated strip and they'll get what they need to die in the treated strip. Um, so there's an extreme example of droplet size, right? Nothing and then something. Um so it just depends. Um, I mean, it really depends on a lot of different factors. Um, you know, the more water, uh, you would think intuitively it's gonna be better. Um, you know, ground air, you've heard all those arguments, uh, those I I think it's all the same for insects. What do you think, Whitney?
SPEAKER_04Yeah, no, I would agree with that. I mean, obviously, if we talk about a droplet size, we're you know, we if we were gonna make one recommendation, oftentimes we tend to lead lead toward a finer droplet size like a hollow pea, but that's not realistic. We know that's what the majority of insecticide applications are going through, you know, herbicide tips, whether that be an AIXR or whatever else. So it's gonna be a more coarse droplet size. So my argument would be more for just ensuring that we have good coverage through water volume. And again, like Jeremy said, we've seen really good control comparing an airplane to a ground rig, you know, five GPA versus 10 GPA. And so I think most of the time we do get effective control. I think the things we got to think about maybe increasing that GPA are gonna be those products that are that aren't systemic, you know, that coverage is more critical. So then water volume may be more imperative, but does it necessarily impact efficacy? You know, not necessarily, because you know, we're getting good control and people are spraying stuff at all different, you know, variations of droplet sizes and volumes, and and generally the complaint is not based off of coverage, it's that the product itself is not working due to resistance or whatever else.
SPEAKER_00Yeah. Yeah, if I spray all my stuff at 10 gallons an acre, yeah, and I'm going three and a half miles an hour. So, you know, of course I'm gonna get good control. But yeah, somebody going 17 miles an hour across a field, spraying two gallons an acre, uh, with the boom three feet above the canopy. I mean, yeah, then they blame the product. Yeah.
SPEAKER_01Y'all y'all ever drew driven one of those sprayers?
unknownNo.
SPEAKER_01They're awesome. I love we have one, and it's one of my favorite things to do. But it's, you know, I said this in the episode about Dicambo, which, you know, it is what it is, right? But those things aren't built to go slow. You know, them things are built to go.
SPEAKER_00You like in an airplane, don't you? Yeah.
SPEAKER_01And you can you can drive like you're flying an airplane too. I mean, you there was one time I was just spraying a roundup burn down on a on a cover, and I mean, you you look down at the speedometer and you're going 13 miles an hour, and that feels about right, you know. Whereas I've got it set at 15 gallons per acre, the rate controller, and really kind of the optimum speed is seven and a half or eight miles an hour, and it feels like you can walk faster. I mean, it's like you you're barely moving, you know. So it's it's interesting whenever people bring that up. I'm like, man, we got we got to get some people in in these machines, you know, so that you can experience what it's like to drive one. Because I mean, it it feels like you're they're built for speed, man. It's like a NASCAR race, right? It's built for speed. And and I mean, uh, you know, these guys logistically have a lot going on, right? So it makes sense. You've got something that's built to cover a lot of acres. And so I don't know, it's interesting. Next time you're in Tifton, we'll we'll go for a ride. Philip actually just rode in it for the first time today.
SPEAKER_00So And it's amazing you get the control that you get. Yeah, um considering what's going on. So that just says something about just put it, just put the product out at the right time. Yeah. In some fashion, yeah. Get it out.
SPEAKER_01Yeah, when the threshold is met, you put the product out there. And most times, unless you get a rain or something like that, then it's gonna work, right? Yeah.
unknownYeah.
Bt Cotton Value And Resistance Stewardship
SPEAKER_01All right. Um, anything else that we're missing? Anything else y'all want to discuss? We we briefly mentioned bullworm, Whitney, but you know, with things like that that we're not, I mean, a lot of growers remember what it was like to deal with worms, but a lot don't. And so it's, you know, it's a different ball game in and of itself. I had a couple growers around here ask about conventional cotton last year, and I told them don't go down that road because that they don't remember what it was like to fight bull worms or or in our neck of the woods to back a bud worm either.
SPEAKER_04Yeah. Well, and I think that's people often forget they get hung up on resistance and bull worms, and people often forget the value of the technology also applies to budworm, and that's just as significant. And so right now we're fortunate that even if we do start seeing resistance to book, we have products to control it. We also know how to. We already know through 1646 spraying on eggs, like we can effectively make that shift and still manage well, but in a completely, you know, non-BT system, it would be very hard. And and right now, I'm not concerned that we're seeing anything that justifies an insecticide application based off of resistance. What I suspect is happening is when we get drought, heat, you know, all these different stresses that expression is dipping, and we see some worms potentially come through. I'm hopeful that last year we had a really heavy ballworm flight, really heavy pressure. Some worms had come through. We could see it, I think, just due to the sheer volume. But it sounds like this year it'll be lower pressure. I'm hopeful. And hopefully we don't see that. But I think it's just imperative to remember that these worms do have to hatch and they do have to feed and it takes a little bit of time to for them to die. And so oftentimes that doesn't mean it's resistance just because they're lingering a little bit longer. But a lot of times, too, we tell people, at least in the mid-south, that if you're concerned about it and you need to make a plant bug application, acate bifanthrum will buy you a little bit of time until you can make sure that that bit's working. But if there's any situation, we're always happy to stop what we're doing and go look at the field make a collection, whatever else. But any collections we've sent to David Kearns at Texas has come back susceptible. So it's just something to keep on the mind, but not to be panicked about if you know something happens to come through these this three gene technology.
SPEAKER_00Right.
SPEAKER_01Right. Always good to be looking.
SPEAKER_00Yeah, the BT traits, maybe the cry proteins may be slipping on bulworm control. But yeah, like Whitney said, like you said, tobacco bud worm. People forget that soybean looper used to be an economic pest of cotton. Soybean looper. Um, so the the technology still gives us great control. I just uh pulled some pigweeds this morning out of a couple of plots, and it would cover with beet army worms. Beet army worms used to be a significant pest of cotton. So they're still getting their money's worth when it comes to the the full spectrum of of wet pest on the crop with the BT traits.
SPEAKER_01So around here or anybody that's a cotton grower that also plants corn, we try to encourage folks to plant stuff that doesn't have VIP, right? Because that that's you know, selection pressure, right? And that's that's where they're selecting for resistance, is in corn, and then it moves to moves to us, and and we I think it's more valuable in cotton than it is in corn myself. And so we need to preserve the technology in cotton and the corn guys, you know, we're really not losing that much to to corn.
SPEAKER_00Almost every bullworm in a cotton field went through corn in the previous generation as a corn earworm. Almost every one.
SPEAKER_04So and we have lots of data in the mid-south that shows that uh earworm is not economical in corn. And so we would argue you need to be choosing technology based off of boars and not off of earworm, and choose your cotton technology based off of your lips, you know, your your bullworms or your budworms.
unknownYep.
SPEAKER_01Right. Well, good deal.
Key Takeaways And Thanks
SPEAKER_01All right. Well, certainly want to thank Dr. Jeremy McGreen and Dr. Whitney Crow for joining us today, this episode of the Cotton Specials Corner Podcast. A good discussion on best management practices uh with respect to insects. And uh, of course, want to thank Cotton Incorporated for the sponsorship of this effort, and we'll see y'all next time.
SPEAKER_02Well, you take all my money, you take all my pride, you take up all my time, and then you take me for the ride. I got cotton picking, cotton picking, cotton growing blue Lord, I can't live without you, but living with you make a man for blue Well it first it grows so slowly, but I can't make it stop me, worry about you till I'm tired of it. I can take it, I've been growing blue. Oh my god. Well, let's tell you lost the child the pound, you come back with the mixed around the gun, cut and pick it, cut and pick it, cutting growing blue, I can't live without you, it's still the home in my foundative Well if it was the call, you call me, you promised me the moon, and then I wish I wasn't born. I got I can pick it, I'm picking, I've been growing Load I came there without you Living with you what in my gonna do One rain away from glory, but it's still the only life I'd ever choose. Well, I finally made some money, it's the cotton pick and cotton grooving blue.