Arkansas Row Crops Radio

Entomology Update 6-27-24: Fall Army Worms, Plant Bugs, Grasshoppers

June 28, 2024 University of Arkansas System Division of Agriculture

Extension entomologists Ben Thrash and Nick Bateman discuss current populations of fall army worms, plant bugs, grasshoppers and more in Arkansas row crops.


[00:01] Intro/Outro

Arkansas Row Crops Radio, providing up to date information and timely recommendations on row crop production in Arkansas.


[00:12] Ben Thrash

Hey everybody. Today is June 27 and there's still just not a whole lot going on. But there's there's some things we need to talk about what's happening in rice, Nick?


[00:25] Nick Bateman

Well, you come out there and helped us wash weevils, that’s new.


[00:28] Ben Thrash

That is new, that’s not very much fun. I don't like it.


[00:31] Nick Bateman

Talking about weevils, I mean these samples we're looking at larvae. But I will say I did get a few phone calls this week. Some of this, you know, latest planted rice going to flood and it has a ton of adults. So if you're in that boat just be looking out there. You've probably got to stand and went to flood quick enough for your Cruiser should really be doing a good job still. Other thing on stink bugs, you know we talked about it a week or two ago. As far as an 18 goes on Endigo, we're going to have to run out of Tenchu first. There's supposed to be a lot of it out there. Iou can't get your hands on it, call me, because if we run out, we will submit for an 18. Really? The other thing I've been talking about is, I think Ben talked about his beans down at Tiller a few weeks ago and they mowed a hay pasture beside it had a bunch of worms moved into it. I’ve had several folks talk about walking their polypipe line or getting polypipe out on some row rice, some of this there's been catching quite a bit of rain just now getting pipe laid on it and seeing quite a few or seeing a bunch of bushhogs running right now. So just keep in mind if you got some out there or you know, you see any signal grass and it looks like it’s getting burnt up, it’s probably army worms. There's a chance that they move out there into that field. So just, you know, keep that in mind. But and seeing some billbug damage show up some of it's in places that had never seen it before. Our plots up around Newport are pretty chewed up right now. Unfortunately, we just don't have a good foliar option one that I'm comfortable with anyways and they frankly at this point it's probably too late for a foliar anyway. I think at this point you're just going have larvae in the tillers or moving into the soil and there's not much you're going to do about it there. If you can keep it wetter, it'll slow down some but, but unless you can keep it flooded, you're pretty much going to live with it at this point. Outside of that in rice when we're getting real close to a bunch of this starting to head. Seen some pictures and talk to some folks where it’s popping out a few heads and we'll see over the next week or so what stinkbugs are going to do. They’re super easy to find a barnyard grass but if I don't know that's an indicator what we're actually going to see in rice, but that that's pretty much it.


[02:47] Ben Thrash

Yeah. And in cotton I mean it's not, you know, there's not a lot of plant bugs moving into it right now. There are some there are some spots where guys are bordering corn and stuff where they're having to spray, you know, a little bit more. But just nothing that’s setting the world on fire. I will say I made a collection just a few days ago to send down to Mississippi State for some Transform resistance testing. And it was in pig weeds that had a bunch of seed heads in them. And it took me about 5 minutes to collect well over a thousand plant bugs in those pig weeds. So there's a bunch of plant bugs out there. I saw them in my cover crop earlier this year. I can find them in weedy host out there, but I think until those hosts get unpalatable to, I start drawn down from this either hot weather and it stopped raining or you knowjust sensence out we're probably not going to get a lot of them into it until then and until that corn they start moving out of corn you know some of this corn’s behind but anyways so there's a lot of plant bugs out there from what it looks like they just aren't moving into the garden real heavy quite yet you know. Kind of another thing that I've been here and hearing about is there's a few aphids out there. Actually the past couple of years it seems like there really hadn't been that many cotton aphids, but this year I'm getting a few phone calls on them and seen a few even in our plots. So, you know, they all look out for those. You know, our recommendation is just we don't get too worked up about aphids. But if you see them next time you go after plant bugs, use transform and that'll get rid of your your aphid problem. Spider mites, you know, they still don't seem to be too bad, but there's there's a few out there and some spots are going to keep building up. If this hot, dry weather persists, we'll end up getting a few more. So that's kind of all that's happening in cotton right now. But what about what about corn Nick?


[05:11] Nick Bateman

Yeah. You know, still still worried about Southwesterns there really outside of that? Not a lot going on, I guess some of that's getting big enough if it ain’t already tassled out it’s big enough to be worried about stinkbugs second round. But you know, you're talking about finidng that pupae the other day in the stalks getting phone calls on it.


[05:33] Ben Thrash

Yeah.


[05:33] Nick Bateman

Whether it be Europeans or Southwesterns.


[05:38] Ben Thrash

Anything a large yeah. If you're finding if you're finding like pupae out there and you walk out there and you're found in emergence holes, if you're finding emergence holes like within a foot of the ground, those are probably southwestern corn borers. If you're finding them, you know, halfway up the stalk some emergence holes, those are more likely to be European corn borers. But if you're finding any pupae in the stalks, those are those are borers from the first generation. And they're going to emerge and they're going to come right back into your same cornfield. They really don't move, move around too much. So if if that's the case, then you need to be treating because they're going to come back, I’d run something like Besiege. You can run Intrepid if you want to. It's a little cheaper, but you also don't get quite as long of residual control out of it. But if you run one of the diamides, that'll give you several, several weeks of control of the Southwestern corn borers. But, you know, just keep an eye out for them. Check your traps if you got any traps out or be walking out looking for shot holes in the leaves and stuff like that, or split some stalks and look for pupae.


[07:00] Nick Bateman

Hopefullly a bunch of that corn was early enough to avoid quite a bit of that first generation.


[07:08] Ben Thrash

So yeah, hopefully, but what about beans, Nick?


[07:16] Nick Bateman

I've had more phone calls this week folks worried about not finding bugs out there. Yeah, and a few conversations about, you know, beans moving into, like, our R4-ish and getting getting ready to run a fungicide and whether or not we need to put anything for worms in there. And I mean, we're not seeing anything out there. The more flights in general, Ben was looking at his trap numbers early, they’re pretty low. Oh, they're just not going to be that attracted to non-blooming beans. I just don't see the point spraying. So they're automatically.


[07:51] Ben Thrash

Yeah, you know, we're not we're not a big fan of the automatic applications, obviously, but I mean, it is getting close to 4th of July and so usually we have what we call the 4th of July flight and really our moth numbers have not picked up quite yet, but we expect them to pick up pretty soon. And of course, most of this first generation are probably going to be going into corn. Of course, we got corn all different grow stages right now.


[08:22] Nick Bateman

So still a bit of wild host out there, too. Yeah, it may suck up some of those, so.


[08:28] Ben Thrash

Yeah, I don't know.


[08:29] Nick Bateman

I feel like as early as we're planted on a lot of these beans, particularly north of 40. Yeah it it ought to outrun that. We may run into some stinkbugs here over the next couple weeks but it ought to outrun a lot of Caterpillar pests in general.


[08:44] Ben Thrash

We're not even seeing like, I’m not even picking up  green clover worms in the beans I'm sweeping I mean it's kinda, pretty dang quiet. What, maybe too quiet. Yeah, but you know I don't oh yeahwe were going to mention grasshoppers you know there there has seemed to be quite a few grasshoppers out this year. And what do you want to do on them is if you do have like a huge number of grasshoppers in some beans like along the edge of the field or something, you can run Dimlin. You can run straight Dimlin, like four ounces, I think is the rate. As long as those grasshoppers are less than half an inch long, then it'd be like second or third instar once they get up past that, you can't control themwith just Dimlin and they get a lot harder to control after they get some size on them. So really, if you're picking up a lot of them, it's probably a good idea to go ahead and knock them, you know, knock them back. And a lot of times you can just treat the edge of the field or something. And even with the the label on Dimlin, it's got a grassland label on it. So really you can spray grass and stuff around around the field and you really need to really knock those grasshoppers back and get them under control because that's where they're all coming out of. So just keep that in mind. If you if you get a lot of grasshoppers, you know, with Dimlin you can treat all that grass around the edge of the field, but they need to be less than half an inch long. If they're bigger than that, then you're going to have to move to like Besiege. And I think you can run like four ounces and get good control of them with Besiege or you got to move to like a lambda plus acephate or something like that because just a pyrethroid it doesn't do a good job on large, large grasshoppers. So they get pretty tough to control.


[10:51] Nick Bateman

I mean, hot, dry weather, like you mentioned about mites


[10:54] Ben Thrash

Yeah.


[10:55] Nick Bateman

It can increase grasshoppers pretty quick.


[10:57] Ben Thrash

Yeah and there's been plenty of hot, dry weather. We finally got rain the other day, but yeah.


[11:05] Nick Bateman

Well, what about sugarcane aphid? I haven't, you know, we got pictures a few weeks ago and I ain't heard nothing since.


[11:12] Ben Thrash

Yeah. And it's probably because they're just so little acres in the state but you know, keep an eye out for them out there and if you I saw some almost heading it was like in the boot and you could see a few half emerged heads insome I drove by the other day but if you got any sorghum they got planted early and those heads are emerging remember once that stuff goes to flower and you need be looking for for Midge but just keep an eye out for the the sugarcane aphids and Sivanto is really your best product to go to for those sugarcan aphids and so that's all I got.


[11:55] Nick Bateman

Yeah pretty quiet right now.


[11:56] Ben Thrash

Yeah, but if you need us, call us. My number is 5015173853.


[12:02] Nick Bateman

Mine’s 8704568486


[12:06] Ben Thrash

All right, thanks very much.


[12:10] Intro/Outro

Arkansas Row Crops Radio is a production of the University of Arkansas System Division of Agriculture. For more information, please contact your local county extension agent or visit uaex.uada.edu