Weeds AR Wild S3 Ep12. Midseason Weed Control Topic Rundown

Weeds AR Wild S3 Ep12. This week, Dr. Tommy Butts discusses several of the most common weed control themes across the state of Arkansas, including sedges, herbicide cut-off timings, midseason control recommendations, and herbicide injury. 

Transcript

Weeds AR Wild Podcast, S3 Ep12: Midseason Weed Control Topic Rundown

[00:01] Intro/Outro

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

[00:11] Tommy Butts

Welcome the Weeds AR Wild podcast series as a part of Arkansas Row Crops Radio. My name is Tommy Butts, Extension Weed Scientist for the University of Arkansas System Division of Agriculture. And thank you all for joining me for this episode number 12 of the Weeds AR Wild podcast series this year. Today it's just me on here.

[00:32] Tommy Butts

So you only get to hear my wonderful voice today. And the only reason for that is simply because I forgot it was my week to do the podcast and it was too late in the game to try and invite a guest speaker. So, my bad. But I guess unfortunately you'll just get to listen to me today. So, I'm sorry, but you'll just have to grin and bear it with me along here as we go.

[00:51] Tommy Butts

I've got a few topics I wanted to hit on today. Mainly it's just kind of a rundown of a lot of the mid-season weed control topics that have been coming my way. And, you know, I don't think this will be a real long podcast, but just trying to cover our bases on a lot of the main things coming in right now and give some people hopefully some recommendations for what's happening out there.

[1:10] Tommy Butts

So the first thing I wanted to touch on was sedges, because sedge calls keep rolling in and more and more people are finding out how difficult these things have really become to try and control in our rice acres anymore. And the new white-margined sedge is showing its head a lot out there and causing a lot of grief for people.

[1:30] Tommy Butts

So I wanted to hit on that real quick. So just a couple notes on the sedges. So they're, you know, we battle several in the state across our rice acres. Yellow nut sedge is obviously one of the most frequently identified or frequently known. That one's kind of been the most common for a long time. It tends to be a bigger type plant, wider leaf blade to it, a really prominent mid vein on it. If you dig up the roots, you know, you can usually find the rhizomes and maybe even find a nutlet, that kind of thing. That's how you I.D. that one, apart from all the other ones. You know, control options for that are really the best, are still the ALS inhibitors. So we're talking Permit, Permit Plus, Gambit, that kind of thing.

[2:11] Tommy Butts

As far as some of the other ones, you know, we always have rice flatsedge that we're dealing with. It tends to be a little bit finer than what yellow nutsedge is. If you crush it in your fingers and you smell it, it should have a really distinct smell, you know, a cedar pine tree type smell. I don't know how you want to describe it, but it's got a really unique, aromatic smell to it. So you can kind of pick up on that. That's rice flatsedge if you do that. You know that one the especially now this time of year, the Propoanil, Basagrans of the world work real well. Loyant works real well, Rogue post-flood works real well, those kinds of things. 

[2:47] Tommy Butts

There is a little bit of umbrella sedge out there. Not a lot. I don't get too many calls on that. That's probably like our finest sedge that we have. It's real narrow leaves, real tiny kind of little plant to it. But that one we control similarly to rice flatsedge again Basagran and Propanil, Loyant, Rogue should knock it out, that kind of stuff. The one I really wanted to hit on because it's becoming such an animal and I've had a couple consultants call me and just, just basically say that they think this is going to be the next most problematic weed, if not the most problematic weed here in just a couple of years is the white-margined flatedge, because we just do not have good options for trying to manage this thing. So it is another annual flatsedge kind of similar to rice flatsedge. It looks when they're really young, it looks very similar to rice flatsedge. Very tough to distinguish. The only thing I distinguish it apart from rice flatsedge when it's early, like less than six inches, is that if you crush it, it doesn't have the smell to it. That's about the only way I can I.D. it from rice flastsedge. Now, once it starts getting bigger, the underside of the leaf will turn just a sheer white color. Other than the mid vein, the mid vein will stay green, but the leaf itself will just turn a blanket white like it got bleached with Command or something. This animal just gets a whole lot bigger than rice flatsedge though if it grows unchecked. And we've actually seen numerous fields where this thing gets up on top of the rice and then it just sits on top and basically takes the rice down. It just flops it over because it gets so big. So we really got to watch it because this thing is just, just a terrible beast taking down rice if it goes unchecked.

[4:18] Tommy Butts

And unfortunately, we don't have good options for it. So, you know, Sharpen and Bolero are the best residual options. But the problem is a lot of times we're throwing those out, you know, fairly early in our growing season. So, you know, if we're planting beginning or mid-April, that Sharpen is going out, then, you know, Bolero may be coming back like, you know, close to the end of April or something like that. And this one is a late emerger. It's not coming out until mid-May towards the end of May. If we're throwing those, you know, Bolero and Sharpen out in beginning a mid-April, it's not helping us that late in the season. So they're not super helpful. So the best thing I can tell you there is in the future years, try and save Bolero or your RiceBeaux shot, you know, a little bit later in the season, once you're getting closer to kind of that first week in May, that type of thing. You know, if you're planting late, then maybe Sharpen would be a benefit.

[5:06] Tommy Butts

Otherwise those three ounces of Sharpen probably aren't going to be a benefit for you for planting in April. So that's kind of, that's problematic there just it's germination window. Then on top of that, we just don't have great post control options either. Basagran is really, really good on it. The problem I always have is, is trying to get coverage on those sedges, you know, when they're small, those leaves are so upright and so tiny, it's difficult to get a contact herbicide like Basagran on there to kill it once it gets size to it. You know, obviously we can get better coverage, but now it's got a bigger size and it's tougher to kill a bigger sized weed. Then on top of it, we're normally battling these late in the season and the rice canopy is growing. And so we've got to deal with, you know, rice intercepting some of our herbicide and it's not making it into the weeds. So trying to get coverage was something like a contact herbicide. A Basagran is just real, real difficult as well when we get into this season.

[5:57] Tommy Butts

And then another option that works really well but again is difficult is Loyant. So Loyant is really excellent on white-margin sedge as well. But obviously that comes with its whole, you know, bag of tricks with trying to get it applied and where it can go and who's going to, you know, put it out and everything else. So that's a whole nother problem.

[6:15] Tommy Butts

And then outside of that, there's just not really any other options, you know, Facet can do okay on it, maybe suppression type thing. You know, none of the ALS’s work very good on it. Rogue, I've heard mixed reports on, I haven't gotten to do any research with Rogue on white margins yet, but I've heard mixed reports. Some folks have said maybe it's catching it when it's small, but if it gets any size to it, it's kind of blowing through Rogue as well.

[6:39] Tommy Butts

So we're really just we're lacking any significant options for this white margin thing. And so it really comes down to we're going to have to watch it close. We're probably going to have to try and manage it in our off-rice years and in a soybean rotation and get ahead of this thing. Because otherwise, like I said, I've had several consultants call me the last couple of weeks just, just begging for an answer and there's just nothing available right now. So that's pretty rough. But so that kind of hits on the sedges that I wanted to touch on, like I said, just quick, I.D. you know, watch out for this white margin stuff, pay close attention, and then just some of those control options that work best for them. If you have any questions on that sedge front, please feel free to give me a call at any time, too.

[7:18] Tommy Butts

And we can kind of kind of go over that a little bit more in depth or a little bit closer on a case-by-case basis. After the sedges the next thing I wanted a quick hit on that we're moving into is really that in mid-season late season, where we're running into herbicide cutoff timings. And so that's what we really got to start paying attention to as well. On when we need to start start shutting down our herbicide applications in our different crops. You know, for example, rice, a lot of our herbicides start getting shut down at or right after panel initiation right after PI green ring there. Honestly, anything after that, you know, even if that isn't the cut off, everything after PI starts making me a little nervous anyway, because once rice goes reproductive, you know, it just makes me nervous throwing herbicides on reproductive rice because you just never know what that plant might try and do or, you know.

[8:07] Tommy Butts

And as that seed head is forming and moving, you just want as little stress as possible on it at that time. You want it to just be able to focus on that and nothing else. And so, it makes me nervous, any kind of any kind of herbicide after PI, what it might do. You know, one thing to mention here, last year we had a lot of late season Facet applications go out past PI, even past panicle differentiation, you know, joint movement there. And there was a lot of damage from Facet last year. So just be aware, late season Facet applications like that are not a good idea. The same goes like I mentioned for a lot of our other herbicides too. You know, the the grasses of the world rice star clincher those should start getting shut down after pi loins should start getting shut down after pi, all those kinds of things.

[8:53] Tommy Butts

We just don't want to be throwing those different, you know, systemic herbicides or anything else on rice after it goes into the reproductive stages. On the soybean front, you know, it's really honestly quite similar that we were just discussing there with rice. You know, R1, R1 to R2 is generally a cut off for a lot of our herbicides in soybeans. Again, once it's going reproductive you know, I just don't like to, to throw herbicides on top of our crops just trying not to mess with any, any attribute once they go into the reproductive stages because that's just asking for a potential yield hit for some reason. 

[9:31] Tommy Butts

You know, one thing on soybeans I've been getting a lot of calls on is Liberty, right? When can, how much can we push that? And, and, you know, we can maybe push that a little bit, but just be aware that the more blooms that are out, the more chance as we knock blooms off and the bigger chance there is for a yield hit. So just be aware of that. You know, again, with like with a lot of those herbicides and the auxins too, you know, just, just be aware again once we move reproductive, it gets real kind of sketchy as far as what some herbicides might do on a soybean plant as well.

[9:58] Tommy Butts

Also, just a reminder, June 30th is the cutoff for dicamba. So that's coming up here in a couple of weeks. Again, you know, we had so many early planted soybeans this year that most of our soybeans I think, are hitting the, you know, that R1 growth stage already or R2 growth stage. So I don't think the June 30th cut off is going to be a big deal for most people. But, but just be aware that that's coming up as well. And then if you have any questions on these these cut off timings or what they specifically are, we had a publication just a couple of years ago that was the MP 566. It's called Application Cut Off Timings for Common Herbicides. You can get that on our website. You can probably get it from your local county office or county extension agent, you know, or get a hold of us and we can get a get a copy for you.

[10:41] Tommy Butts

But that's a great little handy reference guide just to go through and look at each herbicide and, and what their cut off timings are and those kinds of things. So just know that that's out there and that can help with some of those decisions as well. Another quick topic I wanted to hit on just you know, we went through that drought there for so long and now this past week, it looks like a majority of the state has caught some really, really helpful rainfall and precipitation.

[11:06] Tommy Butts

And so I just wanted to say, you know, even from the weed control front, let's take advantage of this current weather now and help us with our weed control efforts. So the weeds should be a little bit less stressed. Hit them as soon as we possibly can here with that herbicide that we need to try and kill them, because they're just going to be they're going to be trying to grow quick. But right now, when they're less stressed is the best time to try and kill them as well. If we've still got residuals to overlap or we got a ways until we're canopied, make sure we're overlaying other residuals right now. Get those out. You know, there's, there's some potential rain still kind of in the forecast here and there every now and then. So if we can get those out, some of the moisture that's already there will help. But then also maybe we'll catch one of these other showers to fully activate them as well. So get those out where we can. And then one other reminder on our rice. Let's make sure to try and maintain a constant flood as much as possible.

[11:56] Tommy Butts

You know, that cultural practice does wonders for our weed control, but if we have, you know, areas where we let it dry up or we get a dry spot or, you know, we leave for the weekend and we forget about the, you know, getting that watered up before we leave and we get a spot. It just asks for a whole flush of new weeds to come up. And then we're trying to battle them late in the season. And it just it doesn't work great. So maintaining that flood, focusing on water management is a big deal as well and use you again, use our current weather to that take advantage of some of these rainfalls, get that flood, you know, up and hold it high. So that'll help out a lot.

[12:32] Tommy Butts

So that hits on three of those main topics I wanted to hit on sedges, herbicide cut off timings and then using the current weather to our advantage. The last thing that I wanted to hit on, and this is not a fun topic to cover, but man, is it the majority of mine and Tom’s and Jared's and I think Jeremy's phone calls right now, it's just an onslaught of herbicide injury across the board out there right now. And that herbicide injury is coming from a range of reasons, whether it was herbicide drift affecting susceptible crops. I've seen a lot of tank contaminations this year. I've seen a lot of mixing errors this year where we, all the jugs looked similar. We grabbed the wrong jug and we threw in a low rate of a herbicide that wasn't supposed to be in the tank. I can't count on my two hands how many times I've heard that happen this year already, too. So there's just a lot of reasons why we're seeing injury across the board. The first thing I wanted to hit on here was, I know we've all got a million things going on at once right here. You know, we've got a ton of acres to cover everything else because just everything got planted at the same time. The weather, we get small bouts when the weather's actually decent for us to use these herbicides. So we're trying to we're trying to ram them all in, but just make sure to take an extra minute to double check some things. You know, double check that the field we're going to is is actually Clearfield rice and not a conventional you know, make sure that this jug we just picked up is actually, you know, the same chemical we're looking for, even though it may look a little bit the same, you know, make sure. Let's catch that it is. Yep. No, this is actually what I need to throw in the tank right now. You know, just again, take that extra minute to double check some things and it'll save big time on the back end in the long run, both economically, you know, problem wise, anything else, just taking that extra minute to check some of those things will do wonders for us as well.

[14:21] Tommy Butts

And then outside of those types of things where we've actually had mistakes, I'll call them. Right. Drift, tank contaminations, mixing errors. We've also just been hearing a ton of herbicide injury complaints from labeled applications of chemicals. And now I know you know, Jared and I have talked, you know, talked Tom. We've talked to Ford Baldwin quite a bit about some different things. And all of us are kind of puzzled at this point on what the heck is actually kind of the underlying cause of all this other than it just being a crazy environmental condition here. But I can just tell you, we have seen all kinds of different herbicide injuries, and we cannot diagnose all of them on exactly what is causing a bunch of this injury. We've seen, you know, some of this injury is some yellowing, some of it we're seeing a few dead tillers show up. Some of this injury we're seeing is roots not forming and then no other above ground symptoms. I mean, just a hodgepodge of random herbicide injury out there and there's just not a lot of good reasoning that we're finding for why these are occurring from labeled applications.

[15:24] Tommy Butts

So again, the big thing I can tell you here is if you're seeing some herbicide injury, man, you're not the only ones so don't feel bad about it. You know, please feel free to give us a call, send us some pictures. We'll try and do our best. But I'm just telling you right now, there is a lot of injury out there that just is not adding up. You know, there's just not a good reason, logical reason for why some of this is showing up this year. Again, maybe it's just because our weather conditions have been so ebby and flowy. We, you know,  we were cold for so long and all of a sudden we immediately hit these highs and droughts. And then now we caught some rains and we cooled off a little bit and now we're going to heat up again.

[15:57] Tommy Butts

And I don't know, it's just there's a lot going on and it's  the amount of injury we're seeing is really difficult to try and figure out where it's coming from. As far as a recommendation moving forward on how to deal with some of this, there is really no consistent recommendation across the board. Like I said, the injuries we've seen have ranged so wildly that it's tough to make a consistent recommendation on what to do when our injury develops.

[16:20] Tommy Butts

So it's really a situation by situation basis. So if you're looking for, you know, what the best piece of advice is, again, please feel free to give one of us a call, chat with us and we'll try and figure it out on each situational basis. You know, I can tell you, generally speaking, if you've got, particularly with rice, if the flood is on the rice at, you know, at that time and it's going downhill, you know, generally we got to say, you got to take the flood off, let it get some oxygen, let it recover, get a new leaf for a new growth, come in and then put the flood back on and get it going again. In a couple of these situations that we've had, especially particularly with the roots injury that I've talked about, where they just weren't forming any roots, but the above ground part looked completely healthy. You know, a lot of the things I've heard is that the rice doesn't look like it's not, you know, healthy. It looks like it's still trying to grow. And at that point, if the water's on and it's still trying to grow, keep the flood on it right now. Right. Keep letting it go until it actually starts to try and go downhill. You know, hopefully between the fertilizer hitting it now and then, the floodwater keeping going, you know, and less competition with weeds, hopefully those roots just start forming now after these, you know, we get more and more away from some of these herbicide applications. So, again, if it's not going downhill, you know, just keep let it ride. Let that water stay on there. Let that those plants remain unstressed and then keep it moving along with any of our other crops, you know, soybeans, corn, all that kind of stuff. The main thing there is honestly, again, just kind of making sure they're removing any stresses as much as possible. Right. Eliminating weeds where you can, making sure we're running water if we need to, to add some fertilizer. You know, if we're getting into a potassium window in soybeans or something else, make sure that, you know, that fertilizer is out there for all of those crops so that they're not stressing, looking for nutrients as well.

[18:04] Tommy Butts

Again, just if you have some herbicide injury or something else, removing other stresses from the situation is the best thing I can tell you there as well. So again, there's not a lot of good answers there, not a lot of good information on what the heck is actually happening. But just be aware, there's a lot of injury out there and you're not the only one if you're seeing some of it across the across the board there.

[18:25] Tommy Butts

So with that, that pretty much hits on all the topics I wanted to hit on today. So the sedges, the cut off timings, the weather and that ton of herbicide injury we're seeing out there. You know, if you have any questions about those things or, you know, any other tidbits that you want us to know about, like I mentioned, please feel free to get a hold of us, give us a call, shoot us a text message, whatever.

[18:47] Tommy Butts

As always, some of the outreach things. Make sure to check out our website for updated information. If you haven't yet, grab an MP 44 from your local county extension office or download it from online. And I'm already getting a few calls too, if you find some errors or something that doesn't make sense in there, please feel free to let us know too. You know, every year we catch more and more things that we need to edit at the end of the year. And so please let us know because that helps us out once we get to the end of the year. If you catch your mistake, we can make those corrections along the way. So let us know about that. Sign up for our texting service. You just need to text weeds to 501-300-8883. And then, like I've mentioned all throughout this podcast, feel free to get a hold of us any time with questions. So with that, I'm just going to sign off on this podcast. It's been about 20 minutes. I'm sure everyone is sick and tired of hearing only my voice.

[19:38] Tommy Butts

So next time around, I'll make sure to do a little better pre-planning and have a have another guest host on so you don't have to just listen to me the whole time out there. But anyway, I really appreciate y'all listening and the continued support for this Weeds AR Wild podcast series. It's been a, it's been a great little outreach activity and we enjoy doing them. And I've been hearing more and more phone calls come in about just the you know, the appreciation for this podcast and that it's, you know, that the information's been pretty good. So like I said, I appreciate the well-wishes on this podcast and I appreciate it for continuing to listen. So. Oh, and also I should say again to thank you to all our funding sources, you know, our commodity boards, the USDA, industry, you know, support all that kind of stuff because without the support, we wouldn't be able to do this podcast series or a lot of our research that goes to generating a lot of our information as well.

[20:30] Tommy Butts

So thank you for all the support that we have out there from that end as well. But with that, thanks again for listening and thanks for joining us for this episode of the Weeds AR Wild podcast series on Arkansas Road Crops Radio.

[20:44] 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.