Entomology Update 7-3-24: Rice Stink Bugs, Army Worms, Spider Mites

Extension entomologists Nick Bateman and Ben Thrash discuss the current status of rice stink bugs, fall army worms, spider mites and more.

Transcript

[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 July 2nd. And you know, we actually got a little to talk about. Actually today is July 3rd. I'm off. But we got a little bit of stuff to talk about. Sorry we didn't get our one up last week. Uh, I think I said the low end rate was like four ounces of Besiege or something like that, and it's five ounces in beans. So I don't like to get hung up and legal or something like that made it on a post it. So anyways, we'll go over stuff that we were going to talk about last week, again this week and get all that stuff cleared up. So anyways, Nick, what's happening rice?

[00:54] Nick Bateman

Well, there's actually more happening this week than there was last week now that we got some fields headed. And, you know, I think everybody knows this is not uncommon. Those first fields to head having some pretty high numbers and I’ve heard a range, anywhere between some fields being around 30 to 50 and some of them sitting in the seven, eight or ten ballpark. And, you know, if you're running a 30 to 50, that's a no brainer. We've got treat that but those numbers that are running less than ten and really I lean more towards about less than 12 the flower and milk to be honest with you, those numbers really don't scare me. I'm fine with waiting another week on those, come back and check it again because if we're going to run something like a Tenchu, you know, their products going to cost you around 12 bucks on the product itself and another 10 on the airplane. So you're staring down 20 to 22 dollars there. If I’m going to spend that kind of money on stink bug control I want to try to get it to where it’s a one shot done type deal. So if I'm running less than 12, I'd say during flower and milk, I'm probably going to wait to those heads start turning down a little bit, get some soft dough, hard dough out there, and then pull the trigger or something like Tenchu so that it'll it'll give me enough residual to get get out of the season. Also, getting several folks calmed me down about fields that are 20 to 30% headed and having stink bugs. And the other issue there is, you know, we don't recommend you start sweeping those fields to at least 75% head. And the other thing, if you were to treat their field with, say, a Tenchu you know, nobody is going to be protected to what is what has heads out. There's some there is some movement in the plant and some of it might get up into the grain, but it's not going to be enough. So we really want to try to get as many heads out as possible before we treat. So I wouldn't get excited about looking at those fields until until they're at least 75% headed. And I know we're going to talk about army worms here in a little while. Still not getting really in your reports, seeing many out rice, but there's a lot around the state probably hit on that here in a minute. But if y'all are starting to see them please let me know. We're struggling to really kill Armyworms right now with pyrethroids. You know, we've been struggling since 21 there. And so if we're getting them in rice or we need a product, we're we're going to have to submit in 18. So I need know as soon as we start getting some some significant levels of them out there. But that's that's pretty much it in rice.

[03:34] Ben Thrash

Yeah we went looked at a field of beans this morning that, you know, it's pretty grassy and they burn down the grass. And I say that there's quite a few army worms in in those beans this morning. So it seems like there's a there's a few around. But like I said, it was it was a bunch of broadleaf signal grass and stuff out in that field. So that's what they were on before they moved on to beans. So there seems to be seems to be a few around. In cotton, you know, plant bugs seem to have been picking up this past week quite a bit. Mainly it's adults moving into fields. I haven't heard anything, you know, real crazy. It doesn't seem like this year as far as plant bugs go yet, but they are moving into fields. People are having to make applications. Spider mites, spider mites picking up for sure, especially up in Northeast Arkansas. Um, you know, we put out some trials last year and we're going to try to get more out this year. But Abamectin seem to do good in those trials, you know? And remember that product's pretty slow. So if, uh, you know, you spray it out, you got to give it some time. You need to give it a little time to make sure those, those mites are actually going to get under control before you just decide to go back in seven days and treat again. Um, but if you do put Abamectin out, you do give it a couple of weeks and it really doesn't seem to be doing anything, you probably want to come back with a Portal or Zeal. Um, and this, year like, I think I mentioned a couple weeks ago there really has been some aphids this year. And like I mentioned before, our recommendation for aphids is, you know, we don't get too worked up about them. But just on your next plant bug application Transform is really probably your best product to go after them, uh, and just go after your plant bugs and Transform will knock out your aphids same time, um, on another note, you know, look in the forecast for next week, it looks like we got quite a few chances of having scattered showers. Um, so keep that in mind when you're going out with your insecticide application, um, that, you know, mix in a crop oil or, you know, some kind of adjuvant with those insecticides can really improve your rain fastness. Uh, if it does look like you're going to have a inch of rain, you know, in the forecast that we might get some scattered showers and remember acephate has really, really poor rain fastness. Um, Bidrin is, is pretty darn good and Transforms, you know, better than it's better than acephate. So I would, uh, encourage you to stay off the acephate if it looks like you're going to get, get some rain, you know, any time, any time that day or any time probably really within the next 12 hours. Um, see I think that about covers it in cotton. Um, what's happening in corn?

[06:57] Nick Bateman

You know we're starting to see some some pupae show you know from corn borers they're that first generation and and typically those that are cycling out, they're going to move right back into that same field. So if you're seeing some exit holes or split some stalks and find some pupae, those sort of things, keep in mind, you may or may not need to treat again depending on how long ago you treated in conventional corn. I also got a bunch of pictures this week from two or three people. I forgot about this when we were talking earlier, of a bunch of greens and a few browns showing up I mean in typical places where you'd expect them in corn, but, you know, along tree line of that kind of stuff, maybe the first couple hundred foot into the field, kind of like what we see in seedling corn, but stacked up thick on a year, like 15 to 20 on an ear, all up and down those tree lines. And you know, it's going to be, you got bifenthrin which is good on greens. It’s going to be a little difficult to get it to them. But if you're seeing that kind of stink bug level out there on them ears they could cause some damage and potentially some cow horning if those ears aren't totally developed yet that sort of thing so do, do need to be scout again for stink bugs there as well.

[08:17] Ben Thrash

Yeah. Um, the other thing I was going to mention, I guess in, in beans, we've got, uh, you know, we've had these greens and browns showing up, like Nick said, but our bollworm traps have really seemed to start picking up this past week. Now, the majority of those are probably going to be go into corn right now. But, you know, keep an eye out. You can start seeing them out in some bean fields and stuff like that. So now just just be on the lookout for worms out your bean field and, you know, keep an eye out for moths out there being like, what.

[08:56] Nick Bateman

Wouldn't you say? You know, even though those traps are picking up, they’re just kind of historically low for this time of year?

[09:04] Ben Thrash

Yeah. Yeah, it hadn’t been blowout numbers, but just compared to kind of the rest of the year, it's been, uh, you know, definitely elevated. I mean, this is, it's about time for that 4th of July flight. So, you know, tomorrow's 4th of July. So it's that time. It's that time for those moths to be coming in. Um, but grasshoppers in beans, um, some people been seeing quite a few. And the thing is, on grasshoppers, you kind of, you need to get them under control when they’re real small if you're out sleep and a whole bunch of short grasshoppers out your in your beans, you can get those under control with Dimilin when they're under half an inch. And that's probably going to be your cheapest, cheapest option. If they're larger than that, you need to go out with something probably like Besiege or you need to go out with, uh, like a Lambda plus acephate or bifenthrin acephate, something like that. When they get, when they get some size on them, those grasshoppers actually are pretty darn tough to control. So just kind of keep that in mind. Um, and the other thing I'll mention Dimilin does have a grassland label. So if you're up next to a pasture or something like that, you really need to end up spraying that grass out there to get those grasshoppers under control. Um, so just, just keep that in mind if you, uh, cause they're just going to keep coming in from that grass, um, if you're along, if you're along a field, you know, so just kind of keep that in mind. If you had got a bunch of grasshoppers out in your field, um, is there anything else we’re missing Nick?

[10:54] Nick Bateman

Uh, back on the greens and browns thing and beans. You know, I feel like a lot of the reports I'm getting are running 80 to 90% greens. Not, not really that many browns out there. And questions on control there. You know, like Lambda versus bifenthrin when it comes to greens, there ain't a whole lot of difference. Bifenthrin might have a slight edge, but I don't even know if it's measurable. But if that ratio were reversed toward it was mostly browns that's when we really need to start considering acephate. We just wanted to kind of clarify either I think there was maybe some confusion on when to use acephate verses lambda verses bifenthrin there but I mean honestly with it being greens it really doesn’t matter. Pick your poison.

[11:49] Ben Thrash

Yeah. That's about all I got.

[11:50] Nick Bateman

Yeah, same.

[11:52] Ben Thrash

So, well, uh, if you need us, call us my number 5015173853.

[12:01] Nick Bateman

Mine’s 8704568486

[12:07] Ben Thrash

All right. Well, thank you very much.

[12:11] 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.