Weeds AR Wild S4 Ep7: Bottom of the 4th Rain Delay with Dr. Bob Scott and Dr. Tom Barber

Extension weed scientists Bob Scott and Tom Barber discuss dealing with recent rain delays, off target movement and more.

Transcript

Intro/Outro

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

[00:12] Tom Barber

Welcome to the Weeds AR Wild podcast series as a part of Arkansas Row Crops Radio. Hi, my name's Tom Barber. I'm an extension weed scientist by day and interim associate vice president for Ag Natural Resources by night. And I'm happy to be with you today. It's my first podcast in a while, so I've been slacking off due to the other things that have hit my desk. But Bob's letting me be on the program today. So, Dr. Bob Scott, the full-time weed scientist for the U of A Division of Ag, is joining me. Welcome, Bob.

[00:43] Bob Scott

You're, you're my boss now. So I think you let me be on your podcast. It has to be that way. Yeah.

[00:50] Tom Barber

Well, I missed it. I'll tell you, I like these. It’s good, good information. And for those of you wondering why you haven't been seeing it on slick text, I guess we kind of got that figured out. So hopefully we'll be getting, getting those out on the slick text app again in the text, in your text message for those of you that like to get the updates that way. So just to provide that for a little bit. So Bob, we got a lot of things going on. We had a lot of great plans Monday morning to get a lot of treatments put out. And like many of you out there, the rain has been a detriment to some of our herbicide treatments this year and just overall plans of getting everything done. And so, you know, I think that's, you know, that's probably where we need to start up. We got several places we want to touch on today a little bit on off target movement. But first, just talk about timings and what's going on and some of the main calls or texts that I'm getting is just what do we do when the weather won’t cooperate? And it sets us back a little bit?

[01:53] Bob Scott

Well, definitely that's what we were doing. Hurry up and wait. We had about 150 bottles we're ready to spray Monday. And is it going to rain? Is it not going to rain? You don't want to put out that much work and then have a rain come 2 hours later and wash away your all your research. I don't want that any more than I know you guys out there in the field want to see a treatment go to waste in a field. So but, you know, for us, it just means we push our treatments back a little ways. We still put the same thing out. Not a lot of thought has to go into that. But Tom, the calls I'm getting right now, they're starting to get, we're starting to get into that area of no man's land or making recommendations because, you know, when you start talking about tillering grass in rice and pig weed starts getting bigger than what we'd like to see them as a target species, you start kind of going out on a limb with recommendations. You start upping rates where you can if you're not already maxed out on rates and start putting tank mixes together, I guess I'll start on one on rice that I had. You know, where we're starting to see ,I'm starting a lot of calls on RiceStar and that usually means that we're seeing some bigger grass out there that we, and this probably already made it through a good residual program and it's probably already made it through maybe a shot of propanil or something else that hasn't controlled it. And so we're looking at putting out some RiceStar. And one of the one of the things I get asked about a lot is tank mixes with these kind of things. And I always want to ask, well, how big is the grass? What are we really trying to do with this treatment? If there's a little bit of sedge out there, there's a little bit of smart weed, you know, we might be better off to run that full rate of RiceStar by itself. Don't antagonize the grass herbicide. Let's let it do its thing, then put a couple of days in and then go after the broadleaf. So we're just getting into some things like that where we miss the exact timing. We got to start, you know, getting creative on some of these follow up applications.

[04:08] Tom Barber

Yeah, and I think we've talked about this, but I've had that question this week already. You know, I've got big grass, what's my best shot, you know, and what do I mix together to get that done? And you know, just on our previous research, I like RiceStar and Beyond or Postscript. I like RiceStar and Regiment sometimes if we don't have soybeans neighboring our rice field and if we can we can do it without getting in on the beans. But I think a lot of people in all crops are having similar questions. I know in cotton oh, cotton doesn’t like cloudy weather. So if you've been under thunderstorms lately, your cotton is probably not happy. And we've been getting a lot of questions and pictures of just funky looking cotton and what's going on, you know, and a lot of it gets blamed on herbicide. But to be honest with you, a lot of it's just physical and environmental conditions on some of the seedling cotton. A lot of it is herbicide. We've got, we rated at our plots yesterday where we've got different pre treatments out in in different thrips technologies and so ThryvOn versus non ThryvOn technologies and you can definitely see a stress on stress effect there with where you had thrips maybe on the non ThryvOn and then your injury from the herbicide. I mean that plant's got to deal with two separate issues and makes it a little harder to recover from under adverse conditions. So in cotton, if your cotton is struggling right now, I know everybody likes to mix four or five different things to go out over the top just to save a trip. But if the cotton is struggling, I would attack the most immediate problem first and then maybe not, you know, dump four or five different herbicide, insecticide combinations on top of it to stress it out even more. And so any time we mix Liberty, Dual, Roundup together or Liberty, Outlook, Roundup or Liberty, Warrant, Roundup, any of those three way combinations on cotton, oh, we're going to get some burn. I mean, there's no doubt about it. There's a lot of solvent in those systems and if we add an insecticide, we can increase that burn even more. So if we've got pig weed problems, I say we just focus on the on the problem at hand and, you know, go after the pig weed first, maybe with just the Liberty and a residual and try to, you know, minimize the amount of solvent that we have going out, burning those leaves and send us back a little further on the cotton side of things. And if there's thrips Intrepid Edge seems to be one of the, I'm not an entomologist, but that seems to be the most common tank mixes that we're putting in with our herbicides that can offer some benefit of the thrips. Doesn't seem to cause as much phyto in a lot of cases. And so anyway, that kind of wraps up some of the the cotton things, but we're missing our timing on pig weeds, especially on pig weeds. And I think, you know, it's just as important when we are able to make that first application that we follow it up within that ten day window as best as we can to get control of these bigger pig weed that are probably too big to kill.

[07:37] Bob Scott

And I really I really like to narrow up that time between post applications, if I can, especially with something like Liberty in beans. If we miss a timing on pig weed rather than waiting 14 days or until you get another flush, you're you really need to concentrate on killing them big ones and hitting them twice within about 7 to 10 days. And we've had, you know, we've had pretty good luck doing that. And I’ll second what you said about cloudy weather and cotton. You know, it's not just cotton that that impacts. You know any crop that's not green and actively growing can be susceptible to herbicide injury. And I mean, we kind of got used to things like Roundup Ready, you know, being pretty bulletproof to Roundup damage, you know, that eventually they got all that variety stuff worked out, Clearfield rice and New Path and you just rarely see injury from those. But you get into things like high card and Provisia, some of those, and get under the wrong conditions, especially high card, maybe with some overlaps and things like that. And you can you can get just some regular old crop injury that doesn't have anything to do with drift. And it, one of the most difficult things that I have in my job is when people send me a photograph of some little, you know, yellow sick rice and they're like, what's what's this? You know? Yeah, what did that? Well, about 50 different things could probably do that. And some of it might be herbicide, but it can be very hard to determine with just just a photo, you kind of need to know the circumstances and kind of look at what's going on around. Are there any patterns in the field and and that sort of thing. And man, it's definitely got more confusing than it used to be before we had herbicide tolerant crops. Now you got to know what field you're in for sure, and you got to know what fields are around you if you're watching, which way the wind's blowing because you think you've got the same crop growing, you know, to the north or whatever. And you got a south wind well you may or may not have the same crop depending on crop tolerance. So unfortunately, too, when we miss timings, when we started getting a little desperate and to get these treatments out, and that's when we tend to make mistakes. So I would just encourage everybody to be really careful out there because unfortunately, probably one of the number one things that I'm getting right now is having to do with herbicide drift on quite a few fields.

[10:19] Tom Barber

Yeah, it always pops up this time of year I think, Bob. I mean the end of May, first part of June, I mean on the end of June, it just seems like historically that's when we get the most calls and it might be what you're talking about. We've got so many different technologies and rice and really in every crop now that, you know, it's sometimes it's hard to keep straight when we get in the big hurry planting and everything seems to come to the field in a bulk box now seed wise and a lot of hands touch it a lot more than used to. And so sometimes, you know, we get confused on what feilds planted to what. And so but definitely this time of year is when we're getting a lot of those herbicide drift herbicide calls and I think I made this comment before we started, but last year we saw the same thing and I don't remember many years before last year, so I'll just keep it to that. But whenever we have the extended period of time with northerly winds, winds from the northeast northwest, it seems inevitable that we, the next week or two weeks later, I'll start getting more calls on an herbicide drift where the wind shifted on us or what. So anyway, I know a lot of those are coming in.

[11:35] Bob Scott

Yeah. And it's all over the board really. You know, I had a call the other day on Clincher on corn and that's not pretty, especially when corn's 2 to 3 feet tall it's pretty susceptible to a lot of a lot of that kind of stuff. And, you know, rotten neck corn is not going to make corn that well. I know we've had some other symptomology that I've looked at has been, you know, like I said, going back to rice. I've had Roundup on Rice, I've had a new path on non Clearfield rice. To me those are very hard to tell apart. If you look in Jerry Hardke’s newsletter from this past week, we actually published some pictures of both Roundup and New Path drift onto rice. And one of the interesting things is one of the easy ways to tell if it's New Path or RoundUp is to look for off types.

[12:32] Tom Barber

Big, nice, healthy rice plants.

[12:34] Bob Scott

Biug, nice healthy green ones out there and the rest of them are all yellow and stunted, you know, bottle brush roots and not growing well but them other ones are nice and healthy. They're either volunteer or they're a little contaminant in the seed and they have the Clearfield trait in them. That makes it pretty easy. The absence of that trait, in my mind, sometimes makes it easy to determine that it's that it's Roundup. Those those two kind of look alike. Not much else really makes it look quite like that. There are some maladies of rice, like delayed phytotoxic shock syndrome that looks similar, you know, but but really truly, those two are pretty, pretty similar. And not much else can make them look that way. I had my first I don't know if we're allowed to talk about this, but I had my first cupping on soybean pictures sent to me the other day. And it was it was physical drift that's the good news. They had a nice little pattern out there where they've gotten some dicamba on some young non-dicamba soybeans. So, you know, we do have that that that is still labeled treatment with existing quantities this year. So we need to continue to be diligent about the conditions when when that one goes out as well. You know, and then the other thing that you always get on these calls that can be tough is what do I do next? What I do with this field? You know, I don't know about cotton for I don't know how you judge cotton, but I never liked farm crazy cotton. If the top gets blown out of it, you know...

[14:17] Tom Barber

Makes more cotton

[14:18] Bob Scott

Yeah. Just branches out and makes more cotton. I don't think it does. I think this is the you know, and you got to think about the value of replanting. What herbicides have you put out? Can I replant or have I locked myself in with atrazine on corn man you're locked into corn or grain sorghum and there's some cotton products like that.

[14:39] Tom Barber

Yeah so I'd feel probably better planting beans behind atrazine than I do Brake.

[14:43] Bob Scott

Yes.

[14:45] Tom Barber

And some of these other so.

[14:46] Bob Scott

So you got to decide how to manage it. Usually almost always Tom, I keep a rice crop. It's amazing how rice can recover. The thing to look for is that new shoot coming out of the center of the whorl. Is it green? Or is it less injured than the other leaves that are there? Same thing on soybeans. Is that trifoliate that's coming out, if it's green and looks pretty good, that means that plant is going to probably survive. And it's, and you're always better off yield wise, in my mind to keep the crop. If you've got enough plants per acre. And you know, because when you disk it up, when you start over, you're now you're in a late planting date.

[15:30] Tom Barber

And you might, even though you got plentiful moisture now, by the time you work it all up and start over, it may be gone.

[15:36] Bob Scott

It can be gone on these silt loams.

[15:38] Tom Barber

Time of year, we're three days away from a drought.

[15:40] Bob Scott

Yeah. No, you work it up, you plant it looks beautiful, and then it sits in 90 degrees and it turns into concrete. So I'd much prefer to keep a crop. You know, Jarrod and I were talking last week about this in rice. So I've got to field with little bit of new path or RoundUp damage on it. What do I do? Well, if it's sick and dying and you got water on it, you got a pull the water off. There's argument about giving it a little flush. I prefer if it gets a rain on its own and it just kind of stays moist and has good growing conditions to grow out of that injury. I am guilty of this myself, but for years we recommended and this was before Jarrod, this would have been me and like when Chuck Wilson was Rice agronomist We recommended I don't know how many tons of triple 13 or urea.

[16:32] Tom Barber

Ammonium sulfate.

[16:33] Bob Scott

Ammonium sulfate or put ammonium sulfate on it and, and hope for rain and give it some time. We finally put the research to that and it turns out that you really can't do anything much. The best thing is just to give it time and you don't want to put it under any stress. So you don't want to put that flood on until that rice has started to recover, for example. And I think you could say that about any of these crops that are injured from a herbicide, you don't really want to, if you're going to keep the crop, you don't want to add insult to injury, injuring with a subsequent herbicide application.

[17:12] Tom Barber

Yeah, no, I agree. And you know, I think when you're talking about whether to keep it or not and I think about all these pictures I get, whether it's cotton or beans, everybody's focused on the burnt up leaves, but not as much so on the green terminal that’s right there above the burnt up leaves. The new growth that he was talking about, Bob was talking about. And so cotton is the same way. I mean, I, you know, I would keep, especially this time of year. I got a call today, Cotoran and Brake or I'm sorry Diuron and Brake and just like our plots everything look beautiful before this last two inch rain we got we got this two inch rain and then they come back this week. Look at it. And yeah, the Diuron's causing quite a bit of injury. And so, you know, some of those lower leaves will turn brown. I mean, they'll have that chlorotic interveinal chlorosis and then just turn brown and look like they're going to, you know, and they might fall off. But those lower leaves, pretty much we don't really care about them in the long run anyway.

[18:13] Bob Scott

That's right. They're probably not going to amount to much.

[18:15] Tom Barber

Not going to make it to the end. And so that new, that green terminal at the top, if all ll the leaves are gone on cotton and all I have is the green little speck in that terminal. I will keep it because if I, and as long as I have at least one of those down a foot arrow we're keeping it. And the best thing we can do, like you said, is just wait and see. Because if I replant cotton right now, if I got Brake and Cotoran down I'm not going to beans, I'm not going to be able to go to corn. So I'm stuck anyway. And if I replant cotton today, I better be banking on 850 pounds tops, maybe 900. Now, the last the previous October's have been very kind, I think, to us, harvest wise. And so if we have a good, warm October, you can still make it up. But it's a gamble. You know, we don't usually bank on those warm temperatures in October, so. Oh, you know, for me, if it's cotton, I will keep it for sure right now. And just before you make any rash decisions, I would give it a week and just see what happens. Because cotton, like you said, with rice, cotton can really compensate for loss of stand and come back. And you know, crazy cotton doesn’t scare me. It's not fun to scout but it doesn't scare me. 

[19:33] Bob Scott

See I’m not a cotton guy, I can say whatever I want.

[19:34] Tom Barber

It's not fun to scout, but it can still make.

[19:38] Bob Scott

You know, it's only going to get worse or better, depending on how you look at it. Oh, yeah, there's more crops coming out, more tolerance packages. Some may be going away. Some. Yeah, but I'm looking at a new grain sorghum this year that has herbicide tolerance, and that's probably about all I can say about that. But, you know, we've got HPPD tolerant crops lingering around out there and variations of a couple of others. So, you know.

[20:12] Tom Barber

Well, and I'll give you a prime example. So another call I had this morning was I've got my first volunteer beans in cotton call today. I'll have several more. Oh, but you know, if we got Xtend Flex soybeans that are sulfonylurea tolerant, am I going to get them out of a cotton crop? You know, and it's going to be difficult, I mean, is the answer. And so we've got some work Envoke, it's probably our best option. But you know, with that sulfonylurea tolerance, we're going to just make them pretty sick. I'm not sure we're going to end up killing them at the end, but we can do a pretty good job if the cotton is bigger than five leaves, Envoke you know, a 10th to .15 ounces is our best mixture to try to get a handle on those beans. And if they’re, if they’re STS, you'll still affect them. But it's not going to be, they're not going to be as dead as if they weren't STS I'll put it that way. They're just going to kind of stunt, look, sick most of the year.

[21:15] Bob Scott

You know, turns out we got some corn that can kind of tolerate row rice, I get some calls, and Johnson grass for sure, making it through some of those early applications and those residuals. And you, we’re getting into some weird, quirky things about herbicides like Regiment is real good on corn.

[21:39] Tom Barber

Oh yeah.

[21:39] Bob Scott

For control. Yeah. Grasp, on the other hand is zero. So if you don't want to drift on a corn, Grasp is an option you might want to consider. But if you're trying to get it out of row rice Grasp won't work. 

[21:55] Tom Barber

Would you rather do Regiment or would you rather do Clincher or something like that on corn?

[21:59] Bob Scott

You know I like Regiment pretty good I think I think either one of them will eventually take it down Regiment maybe a little bit more satisfying and quicker. But you're going to kill those terminals with with Clincher. So either one of those are options. I don't know what they cost. I let other people worry about that.

[22:18] Tom Barber

Well, I'll let, Bob and I were part of a text chain earlier today talking about goose grass in row rice. And that's a, that's another one that you might just be living with at the end of the year if it gets any size on it. I don't know. We, we had some good row rice trials at Marianna several years ago, and goose grass was the big one there. And if we didn't put that Prowl down the late pre or early post, at least before the, you know, goose grass will tend to come up a little later. And if you can get the prowl down and activate it before it comes up, you can stay ahead of it. But otherwise...

[22:54] Bob Scott

 Yeah, my, my problem solving moment was to say the best we have is 24 ounces of Rice Star. My educational moment was to say next year, you know, let’s get that full rate of Prowl out. Probably that second shot that goes out, not your initial pre or your delayed pre but that first early post would be a good time for that, that Prowl or Prowl H2O or whatever to go out there. And we do, we do have goose grass in the state that will blow through some Prowl sometime. It’s a tough weed.

[23:30] Tom Barber

It’s a tough weed and if it gets dry, I know you usually row rice fields aren’t like this but if it's in cotton or beans and it has any, you know, any kind of drought type conditions, we're not going to kill it with Roundup. We're better, I've done better in my plots, burning it back with glufosinate than I have RoundUp sometimes. Yeah, it's a tough one, and it's becoming a bigger and bigger issue.

[23:54] Bob Scott

I just got off the phone. Volunteer rice in soybeans. Rice is hard to kill if you..

[24:03] Tom Barber

When you're trying to kill it with RoundUp you can’t kill it.

[24:07] Bob Scott

You can injure the fire out of it and you can blank seed heads all day long. But as far as actually killing it, it's really tough. I kind of like that. Kind of like that Liberty seven days apart on pig weed. I kind of like do two shots of RoundUp at a high rate to get rid of rice and you probably not going to get rid of it. Still working at a seed head suppression treatment, you know, later in the season with something. There’s a lot of odd things out there this year that keep coming up. 

[24:40] Tom Barber

And I was about to say you might mix some Select or like Assure II with it, but if it's Provisia rice Assure II’s not going to work.

[24:49] Bob Scott

You know, for a long, longest time, back in the olden days, they had to get rid of the red program and yeah, late shot a select or Fusilade

[24:59] Tom Barber

Fusilate.

[25:00] Bob Scott

On soybean to prevent the you didn't really kill the rice but the red rice but you stopped it from making seed so we'll get into that. I never dreamed when we put that table together and I've I've got it memorized. Page 28 it occurred in MP 44 was got a lot of this information I'll point that out at this time in the podcast because if you're wondering about those tolerances and stuff, that's where we we post all that or we publish all that.

[25:29] Tom Barber

Yeah, I was joking with somebody. Everybody thinks we put the MP 44 out for, for them and the agents and the consultants and the growers. And I say, yeah, that's true. But it's really for me because I can’t memorize all that crap.

[25:39] Bob Scott

It’s too much.

[25:41] Tom Barber

It's a lot of information in there. Lot of info, good info in there.

[25:45] Bob Scott

You know, Tom, I do want to mention, mention that you said the county agents and before we wrap up, but I do want to just remind everybody that your county agent is there to help you. If you have one of these situations or a drift call or whatever like that, they can come out and help figure out what happened. They may or may not need to call a specialist. Tom Barber's a lot better at it than I am. But, you know, call whoever you want. But, you know, extension's job is to just try to figure out what happened and help make the best recommendation on that crop. And, you know, from a legal standpoint, there are issues that people get into and parties can't get along on that. And I feel a little obligated to mention that that's not really our job, that's the state Plant Board’s job. They they do the official investigation determine cause and and penalties and stuff like that. And, you know, you can call your county agent. We don't report any of these to anybody. So, you know, there is that opportunity there to work it out on the turn row, which is what I prefer before it ever goes any farther. But that is kind of the hierarchy of how these things are handled.

[27:05] Tom Barber

And, you know, and it's when you think about the diversity of crops that we have in the state, whether it's technologies or just crop type, right. And next to one another. I mean, if you told tell me ten years ago or 12 years ago when I was a cotton specialist that you would be growing cotton in Prairie County I would’ve told you you were crazy. But I mean, it's just it's amazing to me that we can have all these diverse cropping systems and really there's going to be some screw ups here and there. But overall, everybody, you know, pays attention and does does a good job. So at the end of the day, we're all in it together. So so anyway, we we appreciate everybody's support. Bob, you got anything?

[27:46] Bob Scott

No, just be careful out there. I know the rain is letting up. I don't know when this thing is going to air, but I know we're going to be going crazy tomorrow and the next day trying to get everything sprayed. But that still means we need to stop when the wind's blowing. We still need to be aware of the other crops around us and stuff like that. And one day is not going to, one or two days is not going to change your circumstance when it comes to herbicide, 1 to 2 weeks definitely will change your circumstances. But I always tell my crew 48 hours don't mean nothing if it, if it means getting it out right versus a screw up. So just watch what you're doing and call us if you have any questions.

[28:26] Tom Barber

I think you've mentioned this before, but as you know, we, I talked to more and more people that are moving back to the glufosinate system this year, whether it's, we hadn't even talked about this due to resistance issues or, you know, whether they just didn't, weren't able to get the dicamba they needed to get or whatever. Oh, you know, spraying in banking hours is going to be our best control and, you know, cloudy weather is not really helping us out on the on the killing side of the glufosinate either right now. So we need some sun. We need some warm temps. And, you know, we need to try to get it out during banking hours if we can, you know, 9 to 5, 9 to 6.

[29:08] Bob Scott

Well, and yeah. I'll add to that and say that I'm not encouraging anybody to be again, not to be reckless. But I will say that I would much rather have a field with a little bit of glufosinate drift than I would glyphosate. It is not as readily translocated as RoundUp. And so, you know, Liberty on rice can look really bad, but in the long run typically doesn’t hurt anything. Now I said that that mean you can go out there again and and be reckless, but it is an easier plank to walk when you know it's going to be okay versus something you don't know.

[29:47] Tom Barber

That's right. You know. All right. Well, you got anything else, we good to wrap this one up? I'm glad you let me be a part of one this time. I know you all have been kind of hogging all the podcast to your cell.

[30:00] Bob Scott

Yeah, and I will say we don't have any dates to give out at this time. Maybe that'll be a next week. But I will remind everybody that our counties are starting to put together field days and IPM meetings. I'm not sure what we call them now, but be sure and take the time. If you can make time to get to those. There's some pretty good things that are going to be shown at some of these. I've been invited to speak at a few, and looking forward to getting back out on the on the circuit, on those to our selves.

[30:31] Tom Barber

Good. Well, we appreciate the listeners out there and thanks for tuning in to the Weeds AR Wild podcast series on Arkansas Row Crops Radio.

[30:41] 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.