Field Crops Webinar Series - Resurgence of Western Bean Cutworm

February 13, 2017

MSU Extension Field Crops Webinar Series 2017 Session 1, 2/13/17 Title: Resurgence of Western Bean Cutworm  Presenter: Dr. Chris DiFonzo

Video Transcript

Good evening everyone. My name is Bruce me however when the mission wasn't about West privilege tonight to be able to do this one of an hour with my colleagues. Jim to Decker and Eric Anderson whose demonstrate you see and rescue County hope and in the northern Michigan our speaker tonight is Dr Christopher Gonzo She's or you know cross and I would just you know Chris is so described even queen although tonight she's going to break out a little bit from the natives and talk a little bit about a mother. That's come into the state in her tenure and constant challenges for us Western because we're we're glad you're here with us tonight we're looking forward to this presentation. OK thanks everybody for being there. I've got kind of some bronchitis going. So if I'm coughing I'll apologize for that ahead of time. So Bruce has asked me to talk about the resurgence of Western being Cut-Worm in the title is a little bit different. There will also touch on Cry one F. corn that is then used the last few years have been advertised for control of western being cut normal talk about what's been going on with that. So for the last few years we've really been pushing the limits of being key corn. We've been sort of over relying on the technology we've had about twenty years to be corn the same as we've had twenty years of Roundup Ready. Sometimes there's unrealistic expectations of what the different. BT traits can do and what pests they control and with all the different traits now all stacked on each other. Pyramid on each other sometimes we couldn't decide confusing technology and trade combinations. People forget what they bought oil and they don't know what what to expect in the in the field. The other thing is that we've put the refuge in the bag which has been great from the compliance standpoint you don't have to plant the separate twenty percent block of non BT or put non BT corn into certain row units the plant. You just dump this stuff into the into the hopper and go. So from an ease of use standpoint from a compliance standpoint that has been a real revolution and it's a and the companies were allowed to drive the percentage of non BT refuge down from twenty percent until mostly five percent now. So western being Cut-Worm is native but non-native It's native to the southwest United States Arizona New Mexico that that area in one thousand nine hundred one pioneers moved across. They encountered this kind of what was described in the late eighteenth hundreds. It began to move across the western part of the United States and it attacked corn and dried beans and that was reported in the early one nine hundred and then it just sat out there for a long period of time so I'll go whoops and show that show that graphic again. It sat out in this western area and then in about two thousand. It started to move east out of Iowa and we don't know why there's different explanations for that but whatever the explanation we tracked it in Michigan in Ohio in two thousand and six and now it is as it's been trapped all across New York state over into Vermont. So this is an insect that it is our own but it was not native to to The Great to the Great Lakes region. Hopefully you can see my pointer to see the adult and egg mass maybe about fifty eggs maybe twenty but on average about fifty. They hatch in about six to seven days and you get the little guys how checking out they will eat their egg mass. So it's hard to see and then they moped through five or six stages until they get to be the very large the largest biggest stage looks a little bit like a corn boar. But it's quite a bit larger. So just a brief explanation. Right now the Western beans are overwintering they're not quite pea pated yet they kind of look like a crinkle cut French fry and they've created a little cell in the in the soil. We've we've got them down dug them out up to sixteen inches down. So people always ask about the winter. Doesn't the winter kill them or can I do tillage and that will kill them. But you know they can get pretty far down and I also suspect this is why Sandy or soil types seem to seem to have more Western being in the area and it's probably because after they puke pate which would be in the spring May and June. This must has to climb her way out of this. Out of this soil and if the soil is too heavy. I wonder if they have a hard time getting out so that maybe the sandy or soil types. I would suspect you have greater survival and greater emergence then we get adult flight. Typically we start to catch the first adults in July we get egg laying and there's one generation and then we get these larvae getting into the into the ears own and causing damage and then they drop to the soil in September late late August September and go down into the soil. This is just some interesting information from the past some trapping in in the central part of Michigan in the sandy area. And this is the number of mobs per trap a pretty typical peak starting to get flight in July is. Begins to peak and then falls down into August and then kind of peters out. As far as egg laying the next graphic that's going to appear is the number of eggs found in scouting and you can see that the egg masses are laid as the moss begin to peak but it's really important the crop stage is extremely important in corn so females really pick out this pretest stage where the tassel is kind of sticking straight up and isn't capsulated or covered by a by a couple of leaves and the larvae will crawl right up into that creek tassel in into that tassel and it's covered by those by that leaf tissue so it's very protective and they will feed in that developing tassel tissue the other stage that is preferred for egg laying is just the tassel stage when the tassels pretty fresh and there's pollen and you will find larvae then either up in the castle as it's opening feeding on pollen or even in the leaf axles feeding on pollen or at this point down into the silks So you've got this really that the females are very much keyed in on a certain plant stage. So sometimes growers will will say well I didn't have these last year but why do I have a Miss year or how come they're in a field a but they're not in field B. and some of that explanation can be simply that a corn field or or corn in a huge region simply did not line up with with peak flight. Either it was in the world stage or it was early planted and it was already done so crop stage is very important for for the rate of infestation and to sort of to. That in mind as we go through this. So only certain beaky traits kill Western being and that's because most of the BT traits that we have were developed for European corn bore control. So among those so cry one a a a cry one a B. some of the original BT proteins have no effect whatsoever on Western being. Cry one F. which came a bit later was sold as Hercule X. one it's the herd likes one trait. It's in a variety of different products including some of the acre Max products smart Stax Power Core all of these contain cry one F as one of the proteins and cry I want to have was marketed as having an impact on Western being and even at the very beginning we sometimes saw cry one F. with a little bit of feeding them so across the top are just pictures of feeding That's very typical from Western being they will feed up in the tip and then open that tip up. And then in certain years you'll get more growth up there. This tip becomes covered with Frasse and eaten kernels. And then they will go down into the side. Sometimes and bore right into the side of the ear and when you open that up. You see an area where maybe five six seven eight kernels are gone but more importantly it's open that up. So this is the kind of damage that we're trying to avoid not just the kernel loss but the quality issue and cry when F. was marketed not just for corn bore but to control Western B.. The other trait that was marketed to control Western being is dip three. Hey this isn't this is a Syngenta trait. That is in some of the agriculture hybrids this protein is not a corn bore protein. It was developed to control other ear pests like corn ear worm an army worm. And it provides excellent control of western being Cut-Worm The problem is that three a day was really developed for the Southern United States where there are more ear pests and it's difficult to get good hybrids in Michigan Ontario Ohio that have this this trait. They may be coming. But the but the hybrids that we have now that have the three A Many people complain that they don't like them that they're not the best yielders So just to keep in mind we've had cry when asked for a number of years for corn bore marketed for Western being as well. And then this which we would be excellent but we just don't have a lot of so back in two thousand and eleven when I was talking to growers about what should you do with your with with corn. You know to scope for Western being compared to corn bore. It's not that difficult but it takes some practice and it takes time. So we always said that you should really key in on your pretax and tassel fields and you have to know something about flight. So you ideally would be trapping Western being in your neighborhood with a bucket trap or some sort of trap you'd see that the trap catches are starting to increase you look around find your pretest on tassel field Scout those for two to three weeks and you would key in on of course your non BT corn your refuge corn or your non BT fields or the organic fields you. Kiana on the bts that don't kill Western being. The B.T.N. the refuge. But if you were planting Diptera which you wouldn't have been or cry What if you really didn't have to scout your BT corn it was marketed for control and you might only want to check your refuge. So back in twenty nine to two thousand and nine ten eleven. This was sort of the scouting recommendation if you had very little amount of time to kind of let these cry when I feel this go and really be keying in on the non BT and the refuge. And the other kind of bts So cry when half was OK but once we started to get more Western being and more plots and more data we found out that it wasn't perfect. I wouldn't call it spectacular. So here is some data from Central Michigan from a trial. Anon BT compared to smart stacks so them. So the non BT there's no control. We would have expected the cry when F. to have pretty good control because that's what guys were buying the crime when F. trade for here's the percentage of years damaged eighty two percent of the non BT about almost twenty kernels gone per year and in that year which was a good mold year about many of these damaged years having mold compared to the Smart stacks with some control. You're still you could look at this as like the glass half empty half full. So it's half full and that while we've gone from eighty two percent of the ears damage down to thirty four. That's great. The percentage of years with mold is a lot less if you want to look at the glass half empty. You know you still have a third of the ears that are fed on which if we were talking about corn bore that would have been that would have been a bad a bad percent control. So yes there was a reduction in. Amaj Yes there was some amount of control but it was not the kind of control. You'd expect with the BT trade on other laps and the greatest impact on these cry when after years was still this quality issue of opening these years up on the tip in the side and in years that had a bad fall then getting sprouting and bomb a toxin in there and having a lot of issues it didn't matter whether you had cry when F. or not twenty sixteen things the wheels started to come off the cart as I said and that started with phone calls in August. Calling about Western being Cut-Worm. And so the following pictures that I'm going to show were collected from around the region Michigan Ohio Pennsylvania New York Indiana people submitting photos to their local extension people who sent it to me and I did these and these photos were sent to the Registrar the company that registers the cry one F. a toxin and they were also sent to E.P.A. as proof of what was happening in in the field. So some of these pictures are anonymous and they come from. People in the field who were maybe consultants or scouts and did not want their name used. So this is a field in South Central Michigan typical western being damaged this is a cry want to feel and it has you can see big larvae they're not affected at all. Multiple larvae Perper era pretty pretty devastated. This is a person from St Joe County Anonymous This is his quote I have a grower I sell seed to called me last week the varieties were smart stacks they were so they were refuge in the bad. Where they were pioneer acre Max. And they said there was significant feeding everywhere and some of these people reported every year fed on maybe not a lot but opening that tip. And here you see different pictures of what looked to be very healthy larvae feeding bristly Keller who who was was on earlier recent pictures again this is from Southwest Michigan in September numerous years damage consecutively. Now of course part of the problem with refuge in the bag from my response standpoint or an extension standpoint is that you don't know what the refuges anymore. It's five percent of the plants and Freddie you you assume. But unless you have checks drips which can be pretty expensive a regular person can't go out there and just eyeball it and say this plant is crying is a cry when F. planet or it's a refuge planet because the refuge. You would expect some damage on five percent. But what Bruce was describing was many years in a row one after another after another so that those caught all can't be refuge plants and he also saw sprouting and what you know looks to be mold and here you can see the damage in the tip with all the press and then just really ugly years in September. This is a picture from John over my or at Purdue I don't know how how how well it comes out on the screen but every single year down this row has Tipper side feeding. So he's saying that there's no Wester being cut worm control another picture from John just a close up of ugliness and this was something very common in the northern tier of Indiana. Dr Eddie Michel is that Ohio State. One of the pushback. That we got when we submitted these pictures was that well maybe these. Maybe this is a mistake. Maybe these are fields that aren't cry one F. fields. Maybe maybe the crop is it making cry when F. for some reason the plants are stressed we hear that a lot. The plants are stressed and they're not making BT So we started Perth purchasing test drips and doing a test and proving it so testing kernels. And if it comes up on the screen when you do these check strips the first line tells you the test is working the second line tells you that it's making BT So these ears although very ugly are making cry one F. And here's another picture and he has many many of these pictures and again a very strong signal here that there is big T.V. in the planet. This is from an agribusiness contact in the southern part of Michigan who actually did some some yield estimates and you can see almost every ear here if you look in a row. Almost every year has some damage and he was estimating based on kernel loss about between eight and nine bushels you know if you have a lot of tip feeding sometimes these tips they don't fill and I don't know if it's because of silk damage from Western being or you know when these tips don't fill. There's not a lot of there's not necessarily a lot of kernels gone but when you get in from the side and they open that up you can get a big area of kernels damaged. He also was looking at the acre Max hybrids with Cry one F. and Hercules hybrids and he was rating them as poor control and you can see the percentage of feeding ninety percent ninety five percent and many years with multiple feeding sites which tells you there might have been multiple larvae there so there was a lot. Out of larvae out there and finally this is some data from Cornell It just so happened that they had some trials out just looking at different hybrids at a couple occasions in New York State and the extension agent pulled a lot of ears not just thirty or forty but four hundred per location. He had two locations one in two and he had just knew to triple pro and those toxins have no effect on Western mean he had a Hercules which has the cry I want to have and you can see those are indistinguishable. So the B. T. that would that is essentially having no control. Was as was doing poorly or they or the cry when F.. Was doing as poorly as a as two proteins that have no effect on Western being. Now some of the argument that we got is well this is a problem with all corn for this year corn was stressed it wasn't making BT But you see his last two treatments of it. Tara and Juric eight hybrids that have the VIP three H. rate have no damage. So this isn't a BT problem. This was a cry one F. problem. So where you had to cry when F. alone. It wasn't doing the job. So why is this happening. We hear a lot of reasons why something like this happens. These were actually what were called Top ten excuses to explain or downplay the failure of cry when f this year and these were compiled by some angry customers in a coffee shop I suppose in Indiana and I couldn't print all ten of them because they weren't fit to print but I did pick out some that when I read them sounded familiar including this issue that. This is the first time we've seen this problem. Well if it's. Not we have data going back a number of years showing as I said that. Cry when F. was OK on Western mean but not spectacular and in heavy pressure in a heavy flight like like like two thousand and ten and we could see some some breakthrough with it. We also get the idea that it was a mild winter it didn't freeze deep enough to kill Western being well I already told you that Western means get over winter a foot down sixteen inches down the other thing is that we have a population of Western being in the Upper Peninsula in driving production in white kidney bean production and they do just fine in the U.P.C. so freezing. These are insects that can can be frozen there below or there below the the the frost line and they and freezing has nothing to do with the mild winter has probably very little to do with it. We get this issue that if the corn is stressed it doesn't make B T Well we've done. We have many many pictures showing the pregnancy test that we're doing to show that BT is being made and then we have this idea that it that these these these moldy kernels Don't matter of will just blow out the back of the combine and based on some of the dog levels this year they're pretty high in some of the some of the lots of corn that are that are coming in including some rejections elevators and then without the trait you paid for the feeding would have been worse. Well I don't know some of these ears. I don't know if it could get much worse when you have two or three Western beings per year and you have damage on every single ear that is not acceptable control. So we're questioning you know why is this really happening. And the first thing is that cry when F. was a corn bore toxin it was not selected to kill Western me and cut our Westerman Cut-Worm was out west living in you know Idaho and Colorado before ten years ago when it moved rapidly across the east and only until it really moved rapidly in the last ten years and got into the majority of the Corn Belt. Did we really have a good test of cry went out on Western bean. So the first thing is I would argue that West that cry when have does not meet the criteria for a good high dose toxin. It's not that great a Western mean the second thing that could be happening is that because crime went up wasn't that great that we're we've selected for the last ten years for Western men Cut-Worms to be resistant to this toxin. Once you have survivors. It's easier to develop resistance and the last thing is this issue of refuge in the bag which is great. I guess from the compliance standpoint and from the planting standpoint. And so all I'm a showing you on the bottom here. The data that I had a few slides back for a month called County showing you the non BT with eighty two percent of the plants damaged and that in the Smart stacks. We brought that we reduced that to thirty percent or so now that smart stacks I didn't tell you a few slides ago that was a block of smart stacks one hundred percent. BT and it still is thirty four percent of that year's damage. Another treatment in that trial that I'm showing you now was the smart stacks with the river the refuge in the bag so five percent non BT and ninety five percent. BT And if you look at the percentage of years damaged and the percentage with mold. It's virtually identical to the non BT. So just from going from a one hundred percent. BLOCK And adding five percent non BT into that treatment. We've essentially negated their rep the the ninety five percent of the project that had BT and it just from going to a rib. Here's another another example of that this is a picture from Ontario where my colleagues are not just working on damage but working on quality issues and you can just look at the pictures across the top. This is non BT corn across the bottom is ribbed corn. So this is BT a non b t mix together and if you look at the DAR and humanists in levels which are the micro toxins. It doesn't matter if it's non BT or smart Stax crib the levels are very high. So you still get a lot of damage and you still get a lot of quality issues we went to this rib. So what I think is happening is at the top here when we had the blocker strips refuge which was a pain in the **** to plant I don't know. But when those larvae hatched into a block of BT they would have been to a block of cry when F. plants. Many of them when they were small were susceptible. Many were killed. Yes you still got some damage. Yes you still got some Bamma toxin. But there was some control there it wasn't great but there was some control. Now we've got refuge in the bag. So some of these larvae hatch out on the BT plant but others their mama puts their egg mass on a non BT plant. So for a few days they're feeding on a perfectly fine none BT plant they get a they get some good nutrition they get a little bigger then they start to move and when larvae are a little larger They're often times less susceptible to BEATY. And on top of it would have doesn't kill them very well. So you can imagine that in the top where you have a black refuge those young most of those die but in the bottom. We get a lot more survivors. So we would postulate that the refuge in a that when you put the refuge in the bag you create a bridge that allows these larvae to survive a few days and begin and get to the point where their gut is not as effect that the BT is not as effective on them and that's just the bridge to allow them to survive. So not only is the talks and not very good but now you've put in not very good talks and mixed in with Refuge. So at this point twenty sixteen is over we're looking ahead to two thousand and seventeen. What what can you do. Well the first thing is that we're sort of back to basics. There's no substitute for trapping mobs. To see when that peak flight is occurring. And I use the trap on the bottom of this green bucket trap. You can use that over and over and over again it's less messy there's no liquid or anything in it and the pheromone. Sits in the in the top here and the males come along and fall into the bucket at night you still can use however they milk jug trap and when we've tested those together they give you the same peak in virtually the same catch The only problem is that this is a little bit. This is more messy. Sometimes when it's windy the liquid can blow out or it can dry up and if it's a big heavy flight. Boy those males. They don't necessarily touch the liquid to die if it's if there's too many in there. So. In milk jug trap the firm own is hung under the cap here and the male kind of bubbles in here. So the milk jug Yes you can make it yourself. It's cheap. You can make as many as you want but it's just a little bit more messy to use but either one is perfectly fine and at the bottom for instance is just some data from Ohio State just showing you kind of a typical trap catch that we would get we can have a peak from like mid August. Sorry mid July. Sometimes our peak is in early August in two thousand and sixteen across the northern segment of Ohio it ranged sort of towards the end of July where the yellow arrow arrows are that's those are the weeks that I would be scouting pretest all in tassel corn in your area. So scouting. So I guess learning to identify egg masses is important question being egg mass is kind of unique it doesn't look like like anything else. It's either put on that tassel leaf at the top or sometimes towards the top of the plant kind of in the collar and they're usually up pretty high as you see here. You can actually if you want to do training train some employees trains and students scouts you can actually mock up an infestation using white out. So here would be an egg mass that tassel it is inside here and so this is one of the tassel leaves and this is a very typical place for an egg mass to be and you can. This is a very elegant here but you can get some white out correction fluid and make a fake little egg mass This one's kind of gross looking but you can make it a little more angular and for training what you're really looking for is when you scout you place the sun behind the canopy that that you're scouting and look up and look for. Masses and they will appear one two three four. There's at least five in this picture and white out will look exactly the same from the other side. So that's a real handy way to scout the other thing is I wear a face shield I just went to Home Depot got a cheapo face shield like you would for a wood chipper it wasn't very expensive and that is really important so that you can continuously look and move very quickly and not have corn leaves hit you in the eye you don't want to worry about that as you're walking and I when I approach a field. The first thing I do is I just start walking. I'm not counting I'm just walking and if I see no egg masses as I'm cruising along then I'm pretty sure that there's not many out there. Once I start to see a masses. That's when I would actually start to do a better job scouting and counting the next thing is don't rely on BT corn for Westerman Cut-Worm control those days are over. And so when you're scouting you're looking at pretest all in tassel corn during the as the flight is ramping up. You would scout everything all non BT all BT If you manage to have some VIP hybrids. I would Scout Scout those last if your time limited but the reality is there isn't a lot of VIP in Michigan. So for the most part right now you're looking at scouting everything and are threshold is five percent infestation. And we've learned the hard way that let's say you scout a field twice once every seven days because of it's still. Went from pretest all the tassels those about a week. I would add that percent infestation up over the two to three weeks. So it's not five percent in one week. The first week there might be one. Percent. If the next week is four percent. Now your five percent and you pull the pull the trigger and the trigger. I should say would be a pirate three and spray. You really probably only have one one to do it. If if it overlapped with with fungicide application. It's probably OK to take makes those. In Canada they use a product called corage and it's a different mode of action a different chemistry they they like it a lot over there but it's many times more expensive than a generic pirate threat or warrior something that we could use in Michigan. So this is sort of a new a new reality we've been used to having BT corn and not having to think about corn and not having to scout it for corn bore. But we're getting to the point where we're going to have to start. I think Scouting. So for more information and I guess I should add back in this here. If you don't know what hybrid that you're planting there is a BT tray table that I publish that you can figure out what hybrid you have and what and what and what types of bts are actually in it so that can be pretty useful you can email me or get on my website and actually find that you will notice that for twenty seventeen Several companies have changed in their C. guides the rating of their B.T.S. on Western be so pioneer comes to mind where they have downgraded. Their efficacy levels based on what they saw in two thousand and sixteen. Other companies have not done that yet. Sara Lee But but pioneer certainly has. So some of the seed guides are really reflecting what the amount of control or lack of control that you might get. So if you want to know more about just the generic biology and management of Western mean in corn and in dried beans. There is in the Journal of I.P.M. there's a paper called Ecology and management of Western Cut-Worm blah blah blah by four of us in the in the region. That's from two thousand and ten. It's free online it's it's easy to read. It's got pictures. It's meant for and I.P.M. kind of audience and that is still that is up for free. You can download it. I think it's probably seven or eight pages something more recent that is excellent. Is a webcast by Julie Peterson at University of Nebraska. It's about maybe thirty five minutes long. And you can just go on to the plant management network and find it click on it and just play it whenever you want and she walks through everything about Western being from biology through biological control cultural control and into pesticide spraying So it's a really nice overview that you can download and watch. So I think that's all that I've got. And I will stop sharing now I think. And we can get back to questions or a chat or whatever else is going on. Thanks Chris. And there we did yes two questions in the in the Q. and A And I think James. I did our best to answer the some of these but let's let's go through that in this as well and there see one question was do Western mean effectually beans and I think you talked a little bit about that in there that it's more of a Dr Dean is than a corn and soybean best and there is. Well you know we have actually done host plant tests. When when Western being first came over. We looked at the old literature from the west and it talked about tomatoes and some other oddball kind of things and we thought well you know Michigan has a lot of vegetable production. So we had my our colleagues in Ontario did a lot of host range tests where we put small larvae on lots of different crops and plants to see if they would eat them and sometimes they would kind of. You know they didn't like soybean then they couldn't complete development on soybean but driving certainly are are are a known host. And they act very differently on dried beans. There are climbing Cut-Worm they live on the ground during the day there's no there's no issue with like a crop timing they will infested at any time and what we think happens is once the corn in an area isn't good anymore. They'll just host switch over to to dry beans but there's no effect on soybean. Another question Chris that we had was from my Lansing of there. This is you know we did the six drought problems were the two sixty two thousand sixteen. I don't buy junk basically and that was a good question and I kind of talked a little bit about what we saw down here in the Southwest or the state differential between you know we had some thunderstorms driven rainfall so we had some really eerie. Is that we're almost like you're gated all season fairly close within five to ten miles of drought stress and so you know so you mean it is not so the question was is was the cry one F. issue because of drought and I think the question is in general is the Western good exacerbated because of your August. This last year was that kind of the major thrust of the problem. Well when I But what I'm not telling you is Western mean last year was bad in the brassica it was bad in Indiana Michigan Ontario got just a nihil ated Ohio New York State. It wasn't just Michigan I mean we had some dry pockets. It was the whole region. And even over into the sand hills of Nebraska. So this is a region wide failure of a top of a toxin and and in places that were drive but like you said there were places in Michigan that were not so dry. So that's not the explanation and we have lots of tests trips to show that there was plenty of BT in these plants even if there was some drought stress away. The other question I guess is a commodity that you're going to chant on and there you were talking about a little bit about. Well I guess. James would like you talk a little bit about how you use traffic counts to time your field scouting kind of optimally. So what's sometimes trapping for one year doesn't help you so much but with your trap for a few years you begin to see how in your area when you start to see that ramping up. You know a catch will go. You have one the first week and then four and then all of a sudden you get a week where you know you're getting. Forty. That's the beginning of the increase and in certain areas like the central part of Michigan. Some weeks you'll get one hundred one hundred fifty two hundred now for the western U.S. That wouldn't be a lot but for us. That's a lot and there were some sites this year that had multiple you know eight hundred nine hundred thousand when when when you're seeing that ramping up and that beginning to increase and peak. That's when you go out and start scouting the pretax and tassel fields. And then you'll see that catch rapidly kind of fall off once and usually the peak is about a three week. You know that kind of that hump is about a three week help. I know Bruce you are you also had some some some trap catches down your way. I don't know what it what it look like but you don't get like. You don't get a peek that goes eight weeks. You might get flight for eight weeks but that peak is usually a three maybe four week peak and that's your scouting time. And that's that's good. He did. You've you ever come across anything that comes about how they can only in so much as females only in a pretense of porn because it was it was an eye opening experience working with friends up and Conconi when we're looking for a mass is too fast and I have no idea but you know over the years. We used to collect a lot of egg masses out of corn and I got good at being in the female and figuring out likes sometimes you'd even find a part of a row and as you walk that part of the road you think man I would lay eggs here if I were her there'd be a tassel that was you know kind of encapsulated by two leaves they they love that how they pick that out at night I have no idea because in dry beans. That's not what they're doing at all. You know that dry being canopies completely different. So unless I can find a student that wants to sit up there at night with like some kind of like night vision goggles. That's kind of what because that's what kind of what I need you know to figure out what the heck those those e-mails are doing up there and then during the day in corn you'd sometimes find them sitting in the world. They're like it or like in a little leaf actual their little heads peek you know. So during the day they'll just sit there and wait wait for the evening to fly again. There's a couple other questions in there. So when there was a question in there is a you know the numbers were up in two thousand and sixteen. And so kind of. Is it can you expect weather driven to weather conditions to really drive either successful. We had a really good moth flayed up till two thousand and twelve two thousand and twelve was the real drought year that was the hundred four degree days hundred five degree days where it didn't rain for a really long time that really smacked them back for so we had populations just like crumbled in two thousand and twelve probably just females couldn't get water in two thousand and thirteen was really low but starting in two thousand and fourteen. They kind of were starting to come back again. Now we don't. Terrio they've had where they we gave them our Western beings like in two thousand and nine and ten. They've had pretty decent flight for that whole time. So we're just getting back up to what flight was back in twenty two thousand and nine in two thousand and ten and I just attributed it to that two thousand and twelve season was really bad. Plus we started to get some bio control coming in the system some some Paris a toit's and some pretty Asian. So now we have you know we use on cement you there. Another quick question for you. What is the best time to spray gauge wires asked a question. So the best time to spray would be. I mean we're looking for four percent or five percent infestation. So you don't have to worry so much about the timing because the female has done that for you. I mean she's she's the timing because she's picking out what she likes and she's only going to egg lay in a location or on those plants for a matter of two to three weeks and then she's done. So they don't continue to lay egg masses in a field. Once it's you know past that tassel ing and tassel start to dry up. They just aren't interested anymore. So you've got a two to three week window so around that right after pretty tassel just things are starting to to tassel is when the insecticide should be applied. But remember you could have a field that has nothing and you can have a field that has that's over threshold by a lot and it all has to do with timing and moth flight occurring together. So for this pest. It's worth scouting. It's not like or when we have we just have a corner outbreak and most of the people online probably aren't old enough to remember one but when you have a corn or outbreak every field got hit. You know a lot of a lot of times with this pest. It can be very spotty based on planting date of a field in a neighborhood or even by Sandy knoll versus a lower area of the field. Another question. Darrow as to the count rooms cause the moment toxin that we've seen in court. They don't cause it but they're linked and the best data about that and there's going to be a lot more coming out. The folks over in Ontario have done a ton of work over the last four years. So the the pathogens that lead to vomit toxin. Can be there with or without Western Bean if the right weather conditions exist during still king when the when the infection happens there can be infection and then later at the end of the of the year you know growth into the into the tip and you can get bomb a toxin. You could have Western being damage but it's kind of dry or you didn't get infection. So you could have Western being damaged without while the toxin just mold. But when you put them together the the insect opens the ear up causes more damage opens that husk up opens it up on the side and so there's more areas for things to be infected more damage for mold to it to actually start. So they they can go to they don't need to be together. But when they are together and the weather conditions are right it can exacerbate the problem. Yeah and I thought we had we had these issues before Western being ever came into Michigan. You know based on weather conditions but but together they're like synergistic they're worse. You know I think that's true. We were concerned down in this part of the state where we had a lot of damage that that we may have some issues with corn quality and you know we had some down in the fall in there in there are corn. You know a lot of guys but that corn and then wait for prices to come up a little bit in there. So we're going to want to be real careful about thinking about where the moisture has been what that corn was dry to. Hopefully temperatures were set down we had some cold weather in December to get our temperatures driven down pretty good guys and had quite a bit of bomb attacks and had been told in their corn meal really want to think twice about when that corn said as temperatures rise in the DNS They probably I would consider even some of that I'm afraid before we get into Yeah might my recommendation in the fall was to move that off. Farm as quickly as possible and make it someone else's problem because you get a lot of other issues. I did see a question on the on the side about crop crop rotation and I want to make sure that that people understand that and about maybe like tillage or something like that. I've had questions. Can't we just tailor something so remember that these these these things over winter pretty deep and they're very strong flyers. So even if you did deep tillage or something for revenge and killed some that are in your field that doesn't matter because all your neighbors have them in their fields and Dr B. the old Dr being field down the road has there and they are not this isn't a rotation problem like with corn root worm you raise your own rule and when you plant corn the next year you go there are still there. These move around the landscape. It doesn't matter if a field was soybean last year or so be next year they're keying in on corn of a certain stage and flying around the landscape to find that so crop rotation is beside the point. The only the only places where where crops make it different is things do tend to be to be worse. I think when corn and dried beans are together. So in my column County and some of those areas where if a female is loaded with a. And there's no corn for her to find she has an outlet and that's Dr means. In other places. I don't know what she does stick their eggs someplace else who knows but where you have dried beans. I think you certainly kind of keep that population there at a higher level. But the the the laws that come out in the spring. They're move it around the whole landscape they don't care if you had tillage or if you rotate it or not they're just going to look for tassel and pretend. Record. Crispin other question and the infestation levels so Jonathan ask them five percent of station equals five percent of plants with a man says he just won the lot more elaboration on what the actual threshold is yes so out west. They would use a threshold of like eight ten percent back in the day when we first had this past come into the Great Lakes we region. We thought our survival was a lot better. So we kind of have that threshold. It's an action threshold it's not an economic threshold and it was working pretty well till we got to rid corn. And then it just seems like rib corn Who knows but so it's four percent of the plants invested so if you were if you begin to see egg masses as you scout and you kind of put a line in the sand and you count one hundred plants and as you walk that hundred two of them have an egg mass that's two percent. Next week if you come back and you're in some different rows and you find two more in a hundred. That's two percent two into our four. That's four percent. So the egg mass is from last week have already hatched and there's little guys up on the plant and the egg masses that you're seeing in this week are going to have much so spraying that is perfect. You're going to get last week's doods and you're going to get the the ones that are going to hatch out in the next few days. If you wait too long though. And they get in into the ears own like if you waited three weeks to spray after that good. Good luck there. They're down into that year. It's very difficult to get them. OK Just a couple of thoughts in closing Chris now we got it. We probably better sign up to make sure my contract with dinner that I haven't yet but Ken Burns and asked Will this country. I'm this cut worm attract red winged blackbirds and then the other question was just all kind of on the. Varieties are we really kind of at this point not considering varieties as being a good way to control this. So as far as corn hybrids I side of a VIP hybrid which would be excellent from a beauty standpoint I would treat all other corn the same without any regard to. You know that I know of no differences in dried beans. We tend to have problems with varieties that are larger seeded. Because they will feed up into the dry and cause like a few little chews into a kidney bean and then that can get harvested so the smaller stated beans. They're not as much of a problem. So there is a parietal effect in dried beans. The first part of the question I'm already forgetting. By a red winged blackbirds of creation of some sort. Yes I do see birds coming in there just like I did with corn boar. But everybody hates birds too so you know I'd. But but they they will they will they will come in and go up and get sometimes I work at those years. OK James if you've got if you're on in the background there if you want to put that link up with this. I haven't done a word document but if it's not at the moment in there for full everywhere with our We're about to switch over and thanks. I guess I'll stop for a second. Thanks thanks Chris for an excellent presentation and earn a few things we certainly owe Trumper a lot of fields down here and a lot of issues and with Lester mean this year and we're going to be Eric and I will be certainly working in the southwest part of the state to do a little bit more monitoring and try to provide some information about when people lie to us next year. James I think we're in a depressed about wrap this up for tonight. So again thank you very much for participating tonight.

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