Arkansas Row Crops Radio

Entomology Update 8-16-24: Rice Stink Bug in Late Rice, Soybean Loopers, Fall Armyworm in Pastures

August 16, 2024 University of Arkansas System Division of Agriculture

Extension entomologists Nick Bateman discuss the current status of several row crop pests as the growing season comes close to ending. 


[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 August 16th, and, you know, this cropping year's kind of coming to an end, but we still got a little bit of stuff to worry about out there. So Nick, it sounds like stink bugs are really the only thing you got to worry about this time of year in rice. Unless I guess you got an army worm or two.


[00:32] Nick Bateman

Yeah, there's still a few of them lingering around. But I'll tell you, the one thing that my calls have really been about is any of this green rice left out there, and I know we deal with it every year, but stink bugs are moving pretty hard right now, pretty quick into anything green. And everywhere you drive right now, there's combines getting started. And the more of this rice we cut, the more they're going to consolidate down. From a control standpoint, look, I got to tell you at this point, I think it's a Tenchu game. I mean, especially if you got more than two weeks that you need, need to protect it. Too many phone calls on Lambda and coming back with the same numbers to double the number seven days later. We just scouted our trials this morning, seven days after I'm the same as untreated. And that's, that's looking at the nymphs, not just the adults. I mean, same number. So it's it's not doing a whole lot for us. The one thing, though, that I will say where we might be able to save a little bit of money is if you're right around that termination timing. We've been looking at some five ounce and six ounce rates of Tenchu, and I definitely wouldn't run them if I needed good residual. But I'm going to tell you for like a seven day knockdown them reduced rates are doing pretty good. I don't think I would trust those reduced rates if I was trying to get my full two weeks plus out of it, but from a termination timing slash I'm in the last seven days leading up to 60% straw colored kernels. It's not a bad option. and I tell you, with the current forecast, there's rice is going to move quick finish. And so that's going to help us to. And as long as it stays dry stays hot. And that rice is moving it also makes it more difficult for them stink bugs to injure it. Not that you need to ignore them. But just just keep that in mind. That reduced rate may be a good option right there around termination too if if you're running numbers say 15 plus or 50% control with Lambda ain't good enough. So that's that's pretty much where we're at on on that, and I haven't really heard any reports on peck or any of that yet. I think it's too soon. But at the same time we, we didn't really spray a whole lot of stinkbugs, you know, high numbers anyways in this early rice. So, that's that's pretty much it on rice.


[03:00] Ben Thrash

Bout what you got? Man, in cotton. You know, we're getting we're getting pretty near the end. remember, your termination timings for plant bugs is 250 heat units past cut out. Stinkbugs. It's 450 heat units past cut out, and on on spider mites, it's kind of a little more difficult, but it's, I'm going to say it's about 600, heat units past cut out. Now, I would say if you're at 600 and you've got a really bad spider mite population, you're probably going to have to go ahead and treat them again. if I'm at 600 and I've got just a few spider mites out there, I'm probably going to let them let them ride, a little bit, to, you know, until the end. just as long as you don't. You just don't want premature defoliation out there on on your cotton. So you got to kind of watch those spider mites for a while. because they can they can hurt you on the back end. Of course, we don't need that this year with as low as prices are right now. you know, the last effective bloom date has came and went on most of the state. If you're still down in South Arkansas, you know, the last effective bloom dates about August 21st. so that's when you you got about 50% chance of that bloom, making, turning into an actual boll. So just kind of keep that in mind. and think about what you really want to spend money to protect on your, on your cotton plant. let's see, I guess I'll get into these loopers on on soybeans. Man. We got a pretty serious looper flight going on right now, and there's been a lot of Looper applications going out. and really, you're only you're only you got a couple options. It sounds like there's not a lot of Denim, out there. I've heard that if you if you really want Denim, you can get it. but that leaves Intrepid Edge, out there. So if I'm running Intrepid Edge, I'm gonna run 4 or 5 oz. you know, Denim or Intrepid Edge has done a really good job in our trials on these soybean loopers. you know, if you don't need just a whole lot of time, you're just trying to get from, like, R6 to 6.5 or something, and you just need a week or so. you know, you can get about 50% control is kind of what some of our past research has shown with a pound of acephate. I'll say last year, you know, four ounces of regular old Intrepid, plus half a pound of acephate, three quarters of a pound of acephate look pretty good. So if you got a mixture, if you got to make sure loopers and stinkbugs, you need to go out with Intrepid plus acetate, or if it's a bad population, the loopers, I'm not going to skimp and I'm going to run Intrepid Edge. Plus, you know, acephate if you got a bunch of browns out there and if you, if you got green stinkbugs out there, you can run like Lambda, with it, but you're not going to get any help on your loopers from the lambda. you'll get help from from acephate on, on your loopers. Nick, you had mentioned, you had mentioned some salt marsh.


[06:48] Nick Bateman

Yeah. It seems like they're I don't know if I’d say blowing up by no means, but they're definitely present in every field. Several phone calls kind of around the Stuttgart area. Mainly a few, south where those salt marsh are actually causing quite a bit of defoliation out there. I know you sprayed that test out at Marianna last year. They're they're not as easy to control as what what we would expect. As far as like a pyrethroid it by itself, that sort of thing, you're really going to be looking at a tight mix or going with a turn worm product.


[07:27] Ben Thrash

Yeah, they're a little tough.


[07:30] Nick Bateman

So, I think the other thing to mention too Ben, as far as worms go and soybeans, I know y'all deal with a bunch like around your dad's farm and stuff in Conway, these, these velvet beans seem to show up this time of year.


[07:46] Ben Thrash

Yeah, yeah. a lot of we'll get calls, people, you know, aren't used to having velvet beans a lot of times. And so guys think they got earworms in R6 beans, which, you know, I'll say never happens, but 99.9% of the time it doesn't happen. Typically it’s velvet beans. And they can kind of look like a corn earworm. I mean, they got kind of an orangeish head capsule. They got four pairs of pro legs, but they wiggle real violently when you pick them up like a green clover worm, you know? and you can kill them pretty easy, a pyrethroid will kill them. So you might take out some stinkbugs and and a velvet bean caterpillar, just with a shot of Lambda or something like that. But. Oh, that's about that's all I can really think of Nick.


[08:40] Nick Bateman

Outside of that, if you're plant food plots anytime soon, there's still a bunch of falls out there. I’d be watching if I got any, you know, millet, those sort of things. I'd been looking. Keep an eye on it. Don't let it get eat up.


[08:56] Ben Thrash

Yeah for sure. Same thing goes for pastures. So anyways. Well, if you need us, call us. My number is (501) 517-3853.


[09:06] Nick Bateman

Mine’s 870-456-8486.


[09:11] Ben Thrash

Alright, thank you very much.


[09:14] 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 uaex.uada.edu.