Weeds AR Wild S6 Ep4: Pre vs. Post Flood Weed Control in Rice, Cut Off Timings, Controlling Large Grasses

Extension weed scientist Bob Scott, Tom Barber and Jason Norsworthy reminisce after the passing of Dr. Jim Barrentine before they discuss weed control pre and post flood in rice, cut off timings, controlling large grasses 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.

[00:14] Bob Scott

Hello and welcome to this week's episode of The Weeds AR Wild podcast. My name is Bob Scott, and joining me today, I have my fellow weed scientist with the University of Arkansas Division of Ag, Dr. Tom Barber and Dr. Jason Norsworthy. Good morning guys. Can y'all hear me?

[00:33] Tom Barber

Coming in loud and clear. Good morning. 

[00:36] Bob Scott

All right. Well, fellas, I hate to start off on a somber note, but both of y'all, as well as myself, attended a funeral this past week, and I thought that it very mentioning the passing of Doctor Jim Barrentine. For those of you that don't know, Jim, he had a long career weed science career starting off, I think with Eli Lilly, I'm not really sure what all companies he worked for throughout that. Jim was my first department head when I came to the University of Arkansas, and one of the things that was happening during that time is the extension service really wasn't part of the departments on campus. And everybody was really nervous about becoming, you know, in the departments and losing our sections that we had in extension. And Doctor Barrentine proved to be a very valuable asset, and he was very tuned in to the extension side of things. He was a mentor to me, and it was a big loss for all of us. And I just thought it beared mentioning on on the podcast here today. And I know you guys feel the same way.

[01:49] Tom Barber

Yeah. And, you know, as we went through the funeral on Saturday, you know, it was really more of a celebration of life, I would say. And he had such led, such a great life, led by example, was always happy. Bob, I've told you this. You know, my favorite Barrentine story. He was the department head when I was in graduate school, but I was working on a wheat project. We had Italian ryegrass resistance at the time. Who who would have thought it? But at that time it was hold on resistant ryegrass. And every time I say every time, I probably won't ever time. But weekly it seems like I would drive Jim from Fayetteville down to visit with somebody either at little Rock, or we'd go look at my plots, and he always wanted me to visit with the Wheat Board about my project during that time. But, the favorite part of those drives for me is we would stop randomly. Probably wasn't so randomly for Jim, but we'd stop at Clarksville, at the Hardee's. And I was like, why are we stopping at Hardee's in Clarksville, you know? And he could not pass up their biscuit, he said, was the best sausage biscuit that you could get between there and little Rock. And they had the best, freshest coffee. And so we stopped there and it was early in the morning every time we'd go in there. And there's always that table with the locals sitting at it. And every one of them knew Jim. I mean, I don't know how many times he stopped into that Hardee's, but just a random Hardee's at Clarksville where there's, you know, really no reason to stop other than that they got fresh coffee.

[03:18] Bob Scott

So you and you nailed it on the fresh coffee part. I can remember the secretaries telling me whenever we have a meeting, they don't bother making the coffee. And until he's walking in the room, it's going to be brewing when he walks in the room. Because if it's not, he'll say, why don't you make a fresh pot of coffee? And it doesn't matter if they tell him that he just made it, he'd make them make another one. Yeah.

[03:43] Tom Barber

And I was I was happy to see, I guess last year they renamed the Delta Classic to the Barrentine Delta Classic Golf Tournament, which this year will be July the 16th. And obviously, our department appreciates any support from those that are playing and participating and and being involved in that, in that golf tournament. Actually, Jackson, my youngest, got the Barrentine Endowed Scholarship this year for the department. So, he meant a lot to us and our family and our department. And I know that, you know, that was that that will be one of his legacies is getting that going and supporting the crops, soils and environmental science department.

[04:28] Bob Scott

And Jason, he loved that department. And that's a fitting thing for those scholarships to be coming in through a tournament that has his name on it.

[04:37] Jason Norsworthy

It is. And, you know, I mean, Tom, I'm like, what you just said, you know, I had a daughter that came through here and got a degree in crop science, and she just completed a M.S at Purdue in, in weed science. And that scholarship was very instrumental in her being able to go and complete that degree and hundreds of thousands of dollars. I forget what the exact number is now, but I mean, there's hundreds of thousands of dollars that have been brought in to the department and have been given to these crop science kids. And and, you know, there's also I'll say this, there's well, when when available, there's a tremendous focus on eastern Arkansas. Jim was adamant about helping those students in eastern Arkansas, wanting to see those students here at Fayetteville getting a degree in crop science. And, you know, as was mentioned on Saturday, I mean, Jim graduated from Elaine High, and there was something special about those kids that he wanted to make sure they were they were taken care of and has had a profound, profound impact on this department in his, his his legacy is going to carry on for many, many generations.

[05:53] Bob Scott

Well, for the record, I put two kids through the University of Arkansas. Neither one of them had a scholarship from the department. So just I think a lot.

[06:02] Tom Barber

Were they in the department, Bob?

[06:04] Bob Scott

No, no, they weren't, but I was.

[06:06] Tom Barber

That plays a role. Well.

[06:10] Jason Norsworthy

That's the issue there, Bob.

[06:14] Bob Scott

Okay. It's a kind of a requirement then that they'd be in the department. Yeah, I sounded a little like Great Cartwright just then just to throw another name out there. Well, I don't know about you guys, but in terms of getting back to the weed science that's going on right now, I mean, the rice is being flooded, has been flooded. We're starting to lap middles on soybeans. Corn is tasseling and getting big. So we're kind of hitting that summertime. I guess it should be a little bit of a lull. But there's this is also the time when we start getting calls on controlling big grass. We start getting calls on drift, cut off intervals on herbicides and things like that. So that's sort of on the topic of today is some of these things that we're running into in the field. And I thought I would get started by talking about a little bit of late season grass, pre versus post flood weed control and bigger weeds in rice in general. And, you know, one of the first things that I get called on is what is the cutoff on a lot of these herbicides. And I would just encourage you, whatever it is you're thinking about using, be sure and check the cutoff. We've got most of them in the MP44. If you can't find them, they're on the label. I'll see if you guys disagree with me on this. But in general, if you see a pre harvest interval, these will typically be something like 30 or 60 days prior to harvest. Generally on those products, injury to the crop is not a huge concern or they would have a solid cutoff. And if you look at like the label on two 4D, for example, it's got a very narrow window this time of year, pi to half inch internode. If you look at things like Regiment, it's green ring or panicle initiation. Some of those are hard and fast. And frankly, in my own research, I've seen injury past those. If we go out past those cutoff dates, anything. Did I miss anything on that?

[08:28] Jason Norsworthy

No, I think you're right. You know, the auxins, the auxins definitely pay close attention to those. Bob. And I think Regiment was a good one also to touch on which you did.

[08:40] Bob Scott

And so just be aware of that, you know, and then in terms of big grass, we're getting a little bit of rain here and there. We've got a mixed bag of both dry and wet conditions. You know, it seems like there's a whole lot of clincher that's already went out this year. And I was going to bring that back up again. The reason I say that is I had quite a bit of clincher drift on corn. Nothing serious. I mean, there are a few fields that had some significant acres in them, but it wasn't like it went for miles. It was generally the field next door or cutting across the corner of a field or something. But there was a whole lot of clincher that went out early. I'm I'm fine with clincher pre flood on, you know, wet soupy ground generally if you ask me I'm probably going to recommend rice star pre flood if it's dry. And I'm going to recommend clincher a little bit later. Post flood. Bigger grass can be really hard to kill. Everybody has their favorite. To me there's the issue of is it a salvage application? Is the grass so bad that if we don't spray, it's going to go down and we have to keep it from going down? And then there's also the question of just how much grass is out there and is it worth spraying? I usually recommend that two thirds of the target, we'd be out of the water when they go post flood, whether that's with clincher or in a max ace or provisia situation. Anything you guys want to add to the bigger weed control and rice topic?

[10:25] Jason Norsworthy

You know it. It differs, like you said, from field to field. I think some of it is also, what else do you have out there? You know, some of my most recent calls have been big grass with sedge. And so you just you kind of think about what are you going to put together. You know, some of these combinations, you can get antagonism with them. And, you know, Bob, I, you mentioned here just a second ago and I agree with you. I've asked them, you know, if they say they've got barnyard grass and they've got sedge out there. What are you most concerned about, at least from the standpoint of the crop going down? You know, I understand folks don't want to split these, but if you've got a lot of grass out there and a lot of sedge out there, you're probably you may even have to split those applications. I mean, there's just no if ends or buts about it. The other thing I just want to remind everyone of, and I know we're getting kind of late on this, but if you're not clean when you go to flood, you're going to throw a lot more money cleaning up big grass, sedges, weeds. Post flood, you're going to spend a lot more money than you would have if you had been clean before you went to to a flood. And you know, I gave a recommendation this last week. I had a few growers that called, and it was it was big weeds. And, you know, I gave them a recommendation and their comment to me was crap. I mean, that's going to cost me an extra 60, $70 to to clean this up. And you can't guarantee me that that's going to clean it up. And I just hate to I hate it, folks, but when you're in a post flood scenario, I mean, you're having to apply the maximum rate and chances are you're not going to use one single AI. More often than not, you're not going to use one single AI to get effective control.

[12:26] Bob Scott

You know, Jason, that's a good that's a good point. I'm sorry, Tom, I cut you off.

[12:30] Tom Barber

Go ahead.

[12:30] Bob Scott

It's a good point. So if you were sitting there thinking about tank mixing like clincher with some an ALS herbicide, there's some risk for antagonism when you do that. But if you were primarily going after sedges and you just had a little scattered grass, I would probably say two things. One, maybe you go ahead and take tank mixing and hope for the best or two, maybe you just really look at how much grass do you really have on a year when money is tight? Do we really need to throw that money after the clincher? Normally I'm a 100% control guy, but if it's a salvage and it's not going to take my rice down this year, I'll be honest. I might let some of that go. If it's me they're calling. But I like that concept of which one is going to cost me the most. Which one is doing the most damage? What's the real target weed that we're going after? And I do agree with you. If they're both bad, you're probably looking at two shots.

[13:28] Tom Barber

Well, and I think what's messed a lot of folks up over the last two and a half weeks is the or three, I don't know, depending on when it started was just the rain. I mean, the rains a blessing. It's a good thing for all our other crops. The unfortunate part about it is we were ready to go to flood on a lot of this rice when it hit. And so there the period of time, I think some of the folks that went ahead and put out another residual probably benefited from that in this period that we've had and waiting on the ground to dry to put the fertilizer out before we bring the water. But those that did, and I think we're just going to have some grass at the end. I mean, I'm like, y'all, I don't know why we want to burn $100 and may get some, may not get any control of some of this larger stuff. So but my you know, and we've talked about this before and it does cost money. But Regiment rice star beyond rice star I mean or postscript rice star. Those are the ones to me that always do the best in the salvage situation.

[14:30] Jason Norsworthy

Just I'll tell you, Tom, another one that I can add to that I've worked with the last 2 or 3 years and it has looked very good. And that's Rinde which is essentially a regiment facet of premix that back has. I really like like that. But you're right, you know, you know we were talking this morning and it's I just made the comment when the two of us were talking. It's crazy how much big rice we have out there. I'm talking 12 14 inch rice that should have been at flood seven, ten days ago. And the problem is we've got wet ground and folks are trying to dry that ground up to get some nitrogen out there. And as a result of that, the pre floods may have gone out 2 or 3 weeks ago. And if you did not have a strong residual in that pre flood application, you're going to have another flush of of grass. And you know one consideration is, is just like I said right before you drop the water on it, maybe try to come and clean up some of that small grass. I don't like floating up rice when I know I've got grass in the field, because again, it's going to be a lot easier to control it before I go to flood than all of a sudden deciding I've got to do something post flood.

[15:55] Bob Scott

You know, one of the, I think one of the technologies that this really shows up in, because we think about it in terms of post-emerge grass control, is provisioned. Max Ace. And I got to tell you, I'm I get a little bit frustrated. This reminds me of the day, the early days in Clearfield when, you know, we we did all this work looking at it for control of red rice. But what really happened when it went out in the field is the barnyard grass. The crabgrass, the broadly central grass all showed up either before or in combination with red rice, and it turned into more of a general grass recommendation. And I think we're seeing this some with Max ace and where we're going after all the grasses post, you really got to have a residual down with these products. Especially in my opinion with Max ace, I, I think we need to focus those applications on red rice where they belong. And without a good residual program down, you end up focusing on the grass, on the barnyard grass or the other weeds that are out there. Are you guys running into that as well?

[17:07] Jason Norsworthy

Bob I'll just you know, the last I'm going to say the last 14 days, two weeks, 50% of my calls have been centered on Max Ace Rice. And it's either Max Ace Rice not having sufficient tolerance to high card or it's high card, not providing the level of control that the growers had had expected. And you know, I want to address both of those first. From a control standpoint, if I say this every time I talk about high Card, it has isoxadifen in there. Isoxadifen is a safener, Max. Ace rice does not have as good a tolerance to quizalofop, which is the active ingredient in high card. It doesn't have as good of tolerance as does provision of rice. And the problem is, once you start putting a safener in there, you have a tendency also to safen the weeds. And I've done a lot of work to show, and I'm sure you guys have two that, you know, multiple applications of high card, if timely on small grass, we can get very good annual grass control. But when you get behind the eight ball you've got large grass. You may only be spraying it once. You're going to see that high card is not what I would consider a highly, highly effective annual grass material. I'm talking barnyard grass, crabgrass, broadleaf signal grass. It's just it's not as good on that as what we see with with provision. And that's really come to light. I've had a lot of phone calls here over the last few weeks with folks just saying, hey, high card do not perform to where they they thought it would. And I've seen it in fields not only in my plots but in growers fields. I've seen the lack of performance. And then the other thing is a lot of folks individual. Last week we were looking at some rice and there was damage. It was Max rice that was damaged and of course said, why did I not know that under cloudy, wet, cool conditions, that high card has a tendency to injure rice? And I know I've said it on this podcast. I'm going to say it again today. I know that there's going to be in Jared's article on Friday. We're going to see some things in there that's going to talk about this. But going back three weeks ago when it started to rain and the temperatures kind of went down and we had wet conditions out there, I knew that we were going to start seeing issues with Max Ace Rice responding to High Card, and sure enough, that is what's happened and I don't really know what's going on as it relates to Max, ace 7531. But for some reason, that hybrid appears to be much more sensitive to high card than what I'm seeing in the the inbred, the variety inbred that I've worked with for the past several years. Not that I couldn't see some response with it, but I'm confident that what I'm seeing now is this Max ace 7531 appears to be much more sensitive. But folks, if you have wet conditions, if you have cloudy conditions and cooler conditions, you are going to more than likely you're going to see a response. And that response can be very, very severe. I mean, to the tune of actually killing Max Ace Rice, which I, I saw some Max rice this past week that died from a high card application. And no one wants to be in that situation, because obviously that then is going to turn around and lead to having to replant and replanting rice. Here we are going into the second week of June. That's a bad situation to be in. And one other thing I just I'm going to say here, as it relates to ACCase herbicides in general, that would be that would be a rice star provisia, high card. When you spray those herbicides, I would just tell folks, you want to make sure that you're waiting at least probably 48 to 72 hours after you spray those when you flood. If you spray those, and you bring water within 24 hours of making that application, if you bring water to that field and you move that rice from an anaerobic environment to a from, I'm sorry, from an Arabic environment to an anaerobic environment rather quickly before it has a chance really to metabolize or break down that herbicide, you're going to see tremendous, tremendous response. I've demonstrated that time and time again in my research. I've seen that in the field, in growers fields, under wet conditions. That's what we see..

[22:17] Bob Scott

That, that and all of that makes sense if you think about it. Because, I mean, even before we had provision max ace, we've known that clincher works better under cloudy, wet conditions. Soupy, wet. I mean, actually, to get the best activity where I start two to some degree for that matter. So I mean, it all kind of falls into line. Jason, how long so for guys out there in your opinion. And he's spraying a pre flood Max ace he's fertilizing. He's going to he's going to try to clean it up get the fertilizer out. How long do we need to wait to.

[22:55] Jason Norsworthy

I think 72 hours I mean I, I think you're probably fine 42 I think. But you could be just kind of depending on what the conditions are, you could be pushing it at 42 if you've got water on it at 72, if you give that plant essentially three days to try to break down that herbicide, I don't see I'm not going to say that I don't see any response, but I don't see what I would consider a substantial response if I've waited 72 hours before I start moving that rice, an anaerobic environment.

[23:26] Bob Scott

Well, and I know we want that flood on time immediately for the herbicide, but I also know that you can delay that herbicide or that of, I'm sorry, that fertilizer going out, but you could delay that a day. You could wait a day to flood. You're not going to lose that much of it since there's not a soils guy here to defend.

[23:45] Tom Barber

I'm not a soils guy, so I don't know why you put that juju on me Bob.

[23:49] Jason Norsworthy

Make your pre flood application. And I mean if if you can delay your nitrogen one day, two days to get it closer to that that flood. I mean your your pre flood nitrogen and your pre flood herbicide application doesn't have to occur the same day.

[24:07] Jason Norsworthy

And I think that's that's what my recommendation would be, is to make sure that you've got that herbicide application at least three days. And this is specific to I would say specific to high card. I've seen this on provisia. There's less risk with provisia. I've seen it with with rice star. So we're talking to ACCase herbicides. Any of these other herbicides I want them as close to flooding as possible.

[24:36] Bob Scott

So my ask a related question because I've gotten this call as well. And I I've done some work looking at both provisia  and max ace. We did earlier work looking obviously at clincher and other products applied post flood. So I'm pretty comfortable with Max ace post flood. It works on grass, but I don't recall ever doing a trial where we waited 24 hours, 48 hours, 72 hours after that flood was established. Before we put that out, is there a flip side to not putting out a post flood right away when we put that flood on?

[25:17] Jason Norsworthy

What I tell you on that is most folks are not going to put a flood on and then spray within 2 or 3 days because you're putting you're putting that grass under water. And I mean hopefully you don't have do not, do not flood up on eight inch, nine inch, ten inch grass. I just now have I seen that? Yes, I've seen it. But please try to make that application before you go to flood. It comes back to what you just said a moment ago, Bob. I mean, if you've got four inch, five inch grass out there and you going to put a two inch, three inch flood out there in the field, the majority of that grass is at that point under water. And so you're not getting the coverage that you really want. And so I can't think of a scenario where I would tell someone, flood up and then try to kill your grass soon after that.

[26:07] Bob Scott

I like to give that rice. I don't know what the technical term is, but I give that rice a chance to settle down from not only the the change in environment to abiotic with the flood, but also you're hitting it with a slug of urea or nitrogen right there as well. And that, you know, that can cause some issues. I think if you bring the herbicides too fast and too strong, and the last thing we want to have to do is pull the water off because we got rice laying flat on top of it for whatever, for whatever reason. Well, this is a good discussion. I'm going to maybe I'll bookend our rice discussion a little bit by talking about. I have taken a number of calls this week on drift of sulfonylureas, herbicides on soybean, and, you know, one we had one in particular that was an application that was made that they thought they had STS beans, but they didn't. That's not good. But also we have a problem with drift of like permit regiment grasp all the sulfonylureas over on the soybean. There's not a whole lot I can say about that. Except that we can mitigate some of that. If you're planting beans in a field that's surrounded by rice and you know it's liable to get hit, we can plant an STS tolerant or a bolt even better, a bolt variety of soybean, a lot of those herbicides, they can't withstand a direct application. They can of course take permit plus and the ones that are registered for those crops. But a bolt being can better handle a little bit of regiment or grass and not much. But can also mitigate some of that tolerance. But there's been there's been a fair amount of that, that drift going on as well.

[28:08] Jason Norsworthy

Bob, I mean, one thing I want to want to mention there, I mean, I think if you take a look, I think we all three of us would agree the majority of our soybeans in Arkansas are dicamba beans. Okay. And so my understanding correct me if I'm wrong, guys, but bolt is only associated with the enlist trait. And so you know, the guys that are if you're in a heavy, heavy dicamba geography, I hear a lot of guys, they want to plant dicamba partly just to ensure that their neighbor doesn't get on them and vice versa. And I fully understand that. But if you plant dicamba beans, bolt is not going to be an option for you. The best you can do at that point is going to be an STS.

[28:56] Bob Scott

And they may call it an SR.

[28:59] Tom Barber

SR yeah, and I probably going to get in a little bit of trouble by stepping out on this limb here, Bob. But so what blows my mind. And it's happened the last couple of years. And again, it's not all of them. I'm not trying to put all of them in the same bucket. But are some of these drone operators that think that just because they're going slower than an airplane and they're not spraying as wide as a ground sprayer, that drift isn't a problem for them. I can't tell you the number of calls I've gotten on drift and just in general, crop injury due to drone applications, because of the way the rate is spread out across that. Spray width of whatever the drone has. And just because they're not paying as much attention, I guess. I mean, I got a call last week, we're got a drift of roundup all the way across the 60 acre ricefield, enough to where it likely may kill the rice. So they're not safe just because they're a smaller application. I guess it's my point, and I think we really need to take a look at how that application, how that spray is being applied in the distribution of that spray out of the out of the drones, if we're going to continue to use them because it's not it's not good with between crop injury and just weed control failures, because the rate is not correct based on the spray distribution of the pattern. I don't know. We've got issues with a lot of these drone applications, but the other thing is just sheer tank contamination. And I know we've been focused heavily on rice, but in soybean and cotton and corn, I've seen it not to the same degree in rice as I have those crops, probably from a tank contamination standpoint. But taking the time to clean these sprayers, if you're spraying an SR or a bolt bean with Permit Plus, then make sure we clean that out before we just start spraying a bunch of more beans. Good. You know, clean it out. Good. Triple rinsing, using the detergent, all of the small things. It seems like we're skipping some of the small steps this year for some reason, because I it's an overwhelming amount of contamination calls that we're getting or that I'm getting. And then just knowing what's in that bulk container that you get the herbicide in because we're hearing stories that, you know, reusing containers, not knowing what was in them previously, and we're having some crop injury from it. And so, just pay attention to what you're getting, what you're buying, what's in, you know, look inside the container before you start pumping from it to see. Make sure it doesn't look, I guess, funky and multicolored that I'm hearing some horror stories this year. Bob.

[32:07] Bob Scott

I'm getting a lot of those two. Tom. And we are stepping out on a limb. I did have one more note here. Speaking of limbs, and this is not a particular limb I want to stand on, but this is our first year to get the dicamba tolerant, beans back and cotton. And I have to say that so far, I'm fairly pleased that we haven't had a lot of bad, bad situations. But I will say in certain geographies when you drive around, it's pretty easy to pick out the conventional and the enlist beans right now. So we are seeing a little bit of cupping here and there. Like I said, I haven't. Maybe you guys have seen something different, but I haven't seen any, you know, just just terrible fields. I will remind everybody from our previous experience with this technology that typically these beans can handle a light drift of dicamba across them. It doesn't take much to cause some injury where we get into trouble and where we start to see the yield disadvantages and yield destruction is when we get the same fields hit multiple times. And so we need to be very aware that I hope, and I really do hope that guys are out there. I'm hearing stories, but I hope that we're out there using the proper dicamba. The proper tips, following those guidelines, as difficult as they may be to read and understand coming out of the EPA, but doing our best to follow those guidelines to to mitigate that. But I am seeing a few fields here and there. I don't know about you guys. Y'all may not want to comment, but.

[33:49] Tom Barber

They're around. You can you can see.

[33:55] Bob Scott

Anything on cotton or any other crops that you guys want to mention before we wrap this episode up?

[34:04] Tom Barber

Well, I mean, we're in cotton. It's ranging now from 4 to 5 leaf probably to squareing. I'm, you know, I don't get a lot of those calls as far as growth stages. And that is as much as I used to, but but, Zachary and I need to have a podcast just focused on cotton and peanuts, probably because right now we're in the early stages of our weed control programs. I think, you know, we might have mentioned this before, but a lot of guys that were in a strictly camera program learned how good glufosinate was last year on a lot of their problem. Weeds and and nutsedge is one of those weeds. And so roundup and glufosinates been going out on a lot of this ground where we have nutsedge, you know, I was talking to a grower this morning and we were talking about the bout, you know, we were all on this, you know, put Valor out in the fall, Valor out in the spring. One thing that's showing up in our plots, where we do that. Now, granted, most of these plots are completely clean, but nuts edge is a the yellow nuts edge is what is present when we're planting, if nothing else is there, because we've removed it with the Valor. And so we're struggling with nutsedge right now in cotton and, you know, the roundup glufosinate roundup Liberty combination. We put some out last week at Marianna. Rated it and it beats it back pretty good. It's not 100% program, but it's enough to in one application to let the cotton get a competitive advantage. Anyway.

[35:35] Bob Scott

We we can really thank you cotton guys for that roundup Liberty mix because I would have bet Norsworthy’s PhD that that would not be a good mix back when before we could do it. You know, before the crops were tolerant to both. Just because thinking about the way those herbicides work, to me, it still doesn't make a lot of sense. But I cannot deny the results when you put it out. So who knew? Maybe. Maybe Jason can probably explain it, why it works good, but I just know it does.

[36:09] Jason Norsworthy

I think the key to that also, just to kind of build on what you said there, Tom, is making sure that you get that second application out. I think, you know, back in the day, you had to have a minimum of 14 days between those apps. I think that label has since been changed to ten. I don't think it's dropped to seven, but I think it's going to go to ten. And at least on Nut Sedge, it is amazing what you can do on sedge if you'll go ten days between those applications with a full rate of glufosinate I don't know of a post material outside of ALS chemistry that's probably going to be as effective as two applications of glufosinate in terms of taking down nut sedge, and it'll take down some big sedge.

[37:07] Bob Scott

You guys may want to steer away from this one as well, but I still get calls and questions about these cut offs on the Liberty and the roundup label. You know, first bloom on soybeans. First bloom can come very, very early in the crop. And a lot of times we're still spraying. And I'll just be honest with you guys, I since we've got these more modern varieties, I know this used to be a thing in cotton years ago. Don't know that I ever saw an issue from salvage applications of either roundup in any recent times, from either roundup or later applications of Liberty. Obviously the labels there for a reason, but if I've got severe enough weeds that I'm not going to have a good crop anyways, I'm probably going to go ahead and make that application, a little bit late on that first bloom. Have you seen any reason to steer away from that? I really don't know why that restriction is on there, to be honest, because.

[38:18] Tom Barber

I've seen it probably knocking some blooms off. When it gets real hot the environmental conditions are right. But they always recover. One thing we've got going this year and we've talked about this in the past, but because of the dry weather, everybody kind of got an early planning window on their beans. And it seems like these beans are probably more stunted. I won't say stunted, but they're shorter than they usually are when they start blooming. It seems like with that earlier planning date. And so we're not canopied yet, especially on these wide rows when they're blooming, for sure. And that's where a lot of these late applications are coming from.

And you know I'm with you. If you got weeds, especially pigweed you better spray it. You better spray it. You're going to have a mess at the end of the year.

[39:10] Jason Norsworthy

I'm part of a eight state project looking at applications, a United Soybean Board project funded project R1, R2, r three or 4 or 5. And, you know, looking at the data from last year across all of these states, I mean, there was little to no yield loss with those later than labeled applications. But but I do also want to remind our listeners here, and we're not out recommending non labeled applications. I mean these you do need to abide by the label. The label is there for a reason. You know, I'm assuming when I look at this. I've got to think that that label was put on R1 because there's got to be some risk of residue, glufosinate residue showing up in those seed. Based on all the work that I've done as well as others have done. And I've talked to. I hear you, Tom. I've even seen this. We'll get these flowers that you'll knock off. But a lot of times when you go in, you run the combine back through there. Those that doesn't necessarily result in yield loss. And so I'm I'm of the opinion there's got to be more to it than just knocking off a few blooms as to why they have an R1 cutoff. Now, the biggest question that I get from folks is what does an R1 cutoff mean? And when it says in R1 cutoff, does that mean that that is, you can spray up to R one or you if you find a bloom in the field, can you not? Are you not legally able to spray. How do you interpret that label? I think label interpretation is I think if you give a label to ten different folks, you're probably going to get it interpreted different by each individual. I don't know what your thoughts are as to when it says in R1 cut off. Does that mean you can't spray if there's a bloom in the field, or can you spray up until R1?

[41:25] Tom Barber

Yeah, and some label say until or through. So there's a little.

[41:30] Jason Norsworthy

I've seen cut off. I've seen it's it's all those labels are not exactly.

[41:37] Jason Norsworthy

Yeah I've seen the prior to means you shouldn't be fine to bloom.

[41:42] Bob Scott

You know this this all a good point. And you're right. We shouldn't make off label recommendations at all. And I'm like I said, I would prefer they don't. I do think there's also a good case for even in these post-merger times, we're living in a good solid residual program. And this narrower row spacing that we've been preaching for years. I've seen more twin rows this year than I saw a couple of years back. I've seen more drill beans on beds. I know, Tom, you guys like your wide beds in cotton country, but there's no reason you can't plant multiple rows on those beds and close up those rows faster. And boy, it really does make a difference on pigweed control. I mean, we've shown that in every trial that that we've done, Jason, we've we've got a student right now showing that we've showed I showed his data at southern. I stole some of his slides and showed him at southern last year because it's in and used them in my county meetings. So you can get away from even having to worry about bloom. If you put a good residual down, do some narrow roads, you will be canopy closed at closure, you know, at least at bloom.

[42:56] Jason Norsworthy

If you plant drill seeded soybeans and you put a residual down at planting, you're going to come back over those soybeans once and you will be canopied on a wide row bean my experience has shown you're going to spray them at least twice, depending on what the row spacing is and what the environmental conditions have been. So I mean those rows are going to buy you those wider rows going to cost you at least another trip across the field.

[43:26] Tom Barber

And if you're not using, you said it, but if you're not using the residual that planting in combination with those posts, it may be 3 or 4 times.

[43:35] Tom Barber

Yeah, yeah.

[43:37] Jason Norsworthy

You know, the other thing, the other beauty of using these residuals up front and, you know, I think 99% of the folks out there doing this today, but, you know, it's it's rain depending on where you are, it's rained the last three, last three weeks. And you're sitting there, I was talking to a guy the actually this weekend. And his comment to me, he said, man, he said, I'm sure glad I loaded up on residuals because he said, if not, he said the pigweed would be two foot tall before I could get back in and and and spray about every time it gets dry enough to spray. We've caught a rain in some in some areas.

[44:17] Bob Scott

That's a good point, Jason. And it keeps you from doing things like that you don't want to have to do, you know, like salvage. Pigweed is tough. Even with the 24D and dicamba technologies, you can do quick sequential Liberty applications. But again, just like in rice, you're running up a late herbicide bill doing that. When in a year when we when we don't need to. Well, fellows are pushing up against our time again as anybody got any, any last minute things that we didn't mention or we need to say something.

[44:53] Tom Barber

Point out one thing, Bob. So we talked about these application cutoff timings and I thought we had a fact sheet I couldn't remember. But we do. And it took me forever to look it up on the website. So it's easier to Google if you just Google University of Arkansas Division of AG or application cutoff timings for common herbicides. But it's the MP 566 is what it's called. And I'm not saying it's completely up to date, but it's fairly recent.

[45:18] Bob Scott

So and that was the MP566.

[45:21] Tom Barber

566 just Google application cut off timings for common herbicides in the delta.

[45:27] Bob Scott

You and we updated you guys updated that very recently right.

[45:32] Tom Barber

Well not that one. That one I mean not very recently. That was probably 3 or 4 years old.

[45:37] Bob Scott

I must be thinking of the other one then.

[45:41] Bob Scott

These things don't typically change though. 

That's probably not much different.

[45:48] Tom Barber

But that's all I got.

[45:51] Bob Scott

Any final words of wisdom? Anything else?

[45:55] Jason Norsworthy

I enjoyed it guys.

[45:57] Bob Scott

Thank you all for taking the time. And I want to thank everybody for joining us here on The Weeds, our Wild Part podcast, a part of Arkansas Row Crops Radio. As always, all of the research we discussed here today is made possible not only by the division of agriculture, but also by the rice, soybean and soybean promotion boards, as well as the various cotton support groups. And we certainly thank them for our support, and we look forward to talking to you all again next time.

[46:33] 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.