Weeds AR Wild S5 Ep1: Spring Weed Control and Corn Planting (3/19/2025)

Drs. Jason Kelley, Bob Scott and Tom Barber kick off season 5 of Weeds AR Wild with discussions on best options for spring weed control and considerations for corn planting.

Transcript

Weeds AR Wild S5 Ep1: Spring Weed Control and Corn Planting

[00:00] Intro/Outro

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

[00:12] Tom Barber

Hello and welcome to The Weeds AR Wild podcast series as a part of Arkansas Row Crops Radio. My name's Tom Barber. I'm an extension weed scientist with the University of Arkansas System Division of Agriculture. Today on the podcast, this is our first episode of season five. So we're five seasons into this, got a lot of positive feedback on it. We welcome your feedback and welcome any topics that y'all would like to hear us cover on the podcast, as we move through this season. But today I have Dr. Jason Kelly with me and, my counterpart, Dr. Bob Scott over here to help me stay in check on our weed control recommendations. So. Mornin, fellas. How are y'all doing?

[00:49] Jason Kelley

Doing good, Tom. Thank you for having me.

[00:53] Tom Barber

All right, well, let's get started. I know, you know, temperatures are warming up this morning it was kind of cool, but it's warm and cold right now. Typical spring for us. Just had a lot of bad storms in the state in some areas. So our thoughts and prayers go out to those folks affected by the storms. But we still, you know, we're we're ready to move into farming season now and getting a lot of calls about burn down. And Jason, I know you mentioned that, it’d be a good idea for us to do this because you're getting a lot of questions on corn and getting corn in the ground.

[01:25] Jason Kelley

That's right. It's, it's, middle of March. So, you know, it's, have been wet for quite a while, so. But, there's a lot of areas where we're scratching ground right now. There's been some corn go in the ground. You know, about two weeks ago, even. I haven't seen any corn that's emerged yet, but, you know, things are drying out. Some areas, some areas have missed some rains. We're trying to get a little bit of corn in the ground now.

[01:51] Tom Barber

So what are some of the key questions you're getting Jason right now about you know, before they get kicked off and get going hard and heavy here I know it's a competitive sport. Right. Everybody. Once I see one planter rolling down the road, it's game on. Everybody gets nervous.

[02:07] Jason Kelley

Yeah they see it online. And you know somebody said the other day they were just going to hook up the planter and drive around. And yeah.

[02:13] Tom Barber

It just to get it started, haha.

[02:14] Jason Kelley

And no intentions of planting anything. They were just going to go out and, you know, make sure everything was going to work. But yeah, you know, right now I think the the question is, you know, it's middle of March. Is it too early to plant corn? I've heard some farmers say, well, you know, I want to plant soybeans first. And, you know, whether you're planting soybeans or corn, I mean, I think the, you know, getting especially, corn and get getting the stand is the most important thing. And so, you know, our planting rate trials, I mean, it's, you know, it's amazing. I mean, it's, you know, if you got a suboptimal stand, you're in the end, you're going to be disappointed. So, you know, March 18th I think is what today is. So I mean, you know, most of the time I mean you probably a little bit on the early side. But if we can get that stand, you know, that's really what drives the yield is stand. So you know, I was looking out this winter our corn verification program has been in existence 25 years. Well, you know, a long time, you know, time flies. Right. And so went back and all of our data we just I plotted planning day versus yield. And it really came out pretty well. I mean, we had some early planted fields, I think one year, March 9th, all the way out to May 20th. But the yield, you know, we maintain maximum yield from basically middle of March all the way out to about April 25th. And that that lines up really well with our, you know, crop insurance deadline. So, you know, we to me, it's really more important about getting that stand. It's not necessarily the actual planting day, because really, we've got we have 4 to 6 week window in there where we can maximize yield.

[03:56] Tom Barber

Well and we all hope was it ’07? I think I had just started was at ‘07. We got that April/Easter freeze?

[04:03] Jason Kelley

But yeah, that that's still in everybody's mind in my mind as well. You know, that that year we had a lot of, you know, February and March, 80 degree temperatures. And, you know, by the time we got to the end of March, I think about everybody was done planting.

[04:19] Bob Scott

We had wheat back then.

[04:20] Jason Kelley

Back. Yeah. We had we yeah. So that that occurred April 5th, sixth and seventh that year. And so yeah, we had corn that was, a foot tall in some areas, and it got down to 20s, you know, low 20s. And you know that that year there was a lot of replant. But, you know, even that year we learned some lessons that, you know, corn plant, even that year, after about a year, March 25th or 27th, most of that still survived. Yeah. So, you know, we're we're getting that close to the end of March that, you know, to me, if conditions are right it's probably go time.

[04:58] Tom Barber

Gotcha. All right. So what we got to do now is get the weeds out of there first. Right, Bob?

[05:03] Bob Scott

Yeah. I don't know about you, Tom. I've had burndown calls. A lot of questions about the Select plant back to corn and rice. I think it's 30 days at a full rate. And, there is some language on there about a lower rate of Select, but when you're going after ryegrass, you really you're really tied to that higher rate. And it is 30 days. I mean, that's what the label says. And you can injure grass crops with that if you're not careful. So we move into looking at Gramoxone and Gramxone plus a PSII like Atrazine I guess in corn or Metribuzin, right Tom? And, I've, I've dropped my, I've had language about getting these optimum days for cutting burndown out of like warm temperatures before and after. But I think the calendar and the soil temps are catching up with us. It doesn’t matter, haha.

[05:56] Tom Barber

I think the winds blowing about 30 right now. I don't know that I'd recommend it today, haha.

[06:00] Bob Scott

I think if the wind's not blowing though, I'm sprayed. At this point.

[06:04] Tom Barber

And we've been getting some calls on failures with Select at least I have and I’m sure you had to, Bob. And I've dug some up, but if you haven't gone and I just challenge some of you growers and consultants out there, if you hadn't gone and tried to dig some of these clumps ryegrass up, just do it just from an education standpoint, because you'll realize what you're trying to kill. And it may look like just a small tiller and plant on top of the ground, but underneath there's a huge root mass and trying to kill some of these large tiller and clumps right now, Select I think is just not possible even at a high rate. So, I'm with you. I'm switching everybody pretty much to a paraquat based burn down, with a PSII, we get, you mentioned Metribuzin and get a lot of calls about can we still use the 2 or 3oz of Metribuzin and still plant corn? And the answer to that is yes. I know a lot of our, premixes may have 12 months. May have 18 months to corn, depending on the label, but, Metribuzin’s safe prior to plant and corn. And so we can do beans or corn to that rice is where it gets, pretty complicated. And there's really nothing we can…

[07:17] Bob Scott

There’s really not a good one for rice

[07:19] Tom Barber

So and a lot of times, the later you wait, it's two applications of paraquat get that out of there. But, there's a lot of data, both here to Mississippi State and a ton of data out of Mississippi State. Jason Bond’s program over there. You know, not getting the ryegrass out and the detrimental yield results because of that. So especially with grass crops, whether it's corn or rice, it's important to that we burn those down and get that competition out of there before we plant.

[07:49] Bob Scott

Well, and you mentioned Jason Bonds program in Mississippi State. And I, I have to give them a shout out, several of us have been to meetings down on the Gulf Coast and to New Orleans and stuff, and some of those areas that I used to drive through that were grown up in ryegrass. I've been very impressed at how clean those fields were. And they're I think they're a little bit ahead of us on the fall residual, train and getting a really good residual. You can see some lines and some of those fields where they quit spraying. So you knew something had went out post, you know, post harvest or post land prep. And those fields look really clean this year. We didn't have ideal conditions at Newport for our fall burndown stuff because it was dry and we had to go ahead and put it out, and then it stayed dry for a couple weeks. So we didn't have the best activation. But even those plots, you know, I would lots rather be clean in those, than the untreated checks that we didn’t spray there. Just, you know, it's just going to be a lot more of a challenge, where we didn't put that out. So if you're struggling, I guess I say all that to say, if you're struggling, think about next fall. Maybe doing something to keep you out of that off the struggle bus for next spring.

[09:01] Tom Barber

And I can see it driving around just in, in, especially counties in northeast Arkansas where maybe, they put out the residual with the plane and they didn't get close to the edge because and high lines or whatever power lines you see, and you can see the ring of ryegrass around the field where they didn't get it.

[09:19] Jason Kelley

I see a few fields around where they did the opposite. They had ground rig and just went parallel, you know, ring around the field, went around the field, one pass. And, you know, a lot of that ryegrass is going to come out of the ditch or rot anyway. So yeah, you know, they're just trying to keep it from moving out in the field. And yeah those those fields to me I mean there's a little bit of green out there, but they're 95% clean. Still.

[09:40] Tom Barber

Well and this will be more information for later when we get back into the meeting season next year. But we do have some populations in the greenhouse that are very tolerant to Select. Right now, we're in the process of growing those out and doing a little more work on them. But I don't think it's just widespread resistance. Like I say, I think a lot of the failure calls were getting was just too big, and I just don't think it's too I think it's too much for the Select. So switching to that.

[10:06] Bob Scott

I’ll throw this out there. Tom, I've had, both our counterparts in Fayetteville have asked me for, you know, if anyone feels like they have a true failure of Select on ryegrass. In other words, it should have killed it and didn't. We wouldn't mind getting some samples out of those fields. We're not looking for 100 emails, but, if you really feel strongly about it, my contact, your county agent, have him get in touch with us, and, we might if we can beat you out there before you come back with Gramaxone.

[10:38] Tom Barber

That’s the trick, haha.

[10:39] Bob Scott

We’ll to try to get out there and dig up a few of those plants and try to study them and see what's going on, and see if we can do something about it.

[10:49] Tom Barber

Well, and then the other weed I get a lot of calls on is, is may weed and and especially on the prairie region, you know, and really all over we have it in Mariana, too, pretty bad, and it's easy to miss may weed with the wrong herbicide mix and, you know, generally used to RoundUp and first shot would pretty much take it out. But now we have fairly widespread ALS resistant may weed out there in the state. And so it's a little bit trickier to kill. Basically a quart of D has some activity on it depending on the size. It might just suppress it. It might just keep it from growing, you know, any bigger to me, a combo of a hot PPO like a Reviton or a Sharpen or maybe even a Valor if you get it small enough and you use two ounces of Valor, with the 2,4-D seems to be about the best we can do at this point. And then you get the replant questions. You know, how quick and how replant behind that. And so, you know, a lot of people push the envelope on the 24 D, Bob And so a lot, you know, I know what we say for rice anyway, or is 21 days, I think it's 14 days for beans.

[12:05] Bob Scott

And everybody always leaves out the part we say following a rain.

[12:07] Tom Barber

Following a rain.

[12:08] Bob Scott

So, you know, if you get a rain, it really kind of, you can push those plant back envelopes a little bit if you get a decent rainfall. Rainfall really breaks down the phenoxys in general, 2,4-D in particular. So that's when you can cheat. If it's been dry. I worry about cheating on rice or corn.

[12:32] Tom Barber

Absolutely. And we've seen some negative, especially in rice, seen some negative plant populations out there because of that. So just keep that in mind. Valor’s pretty much 30 days to anything other than I mean beans. We know we can apply pre, Peanuts we know we can apply pre. To me I like getting Valor out this time of year, especially if, you know, even if you're working some ground and want to keep it clean before planting. I think you think it gives you a good opportunity.

[12:59] Bob Scott

I think in corn, I mean, I've never seen may weed take a corn field now. So if you can get the suppression you're talking about it with D and the other products you mentioned. I think that's good enough in corn. If you can get it planted and get a stand, it's going to outgrows it. And it may weed. It may have a small effect on yield from the early development of the corn. Jason and I know how that goes, but, but I think the corn and then you're going to come back in here with your corn products like atrazine and all of those, and they're going to wear it out. You know, kind of a so it it can be troublesome if it's thick enough. But I think it ultimately is not a huge issue for corn.

[13:39] Tom Barber

Well, and that you mentioned atrazine and I didn't even have this in my notes to talk about today. But just an update if it's on anybody's mind. The final comment period for atrazine use to the EPA, I think is due sometime in April. And, we don't know what that means, but it generally never takes effect immediately, whatever the decision is. So obviously, even for this year, we're probably good. But we'll keep you updated on any new regulations as, as it pertains to that. So, Jason, any other tips to get us going planter wise or population? 

[14:17] Jason Kelley

Yeah. I mean, you know, getting ready to go the field, I mean, it's, you know, all the planters. We're so electronic driven, right? I mean, we got a iPad or some some electronic pad. We punch in, we want 34,000. We're good to go and we take off planting. Right. Well, those numbers are always right. Right. Haha. Yeah. So, you know, this is my soapbox, I guess. You know, every year there's somebody always calls it where we, we we got a new platner. Sometimes it's new, sometimes it's not. Or, you know, maybe they don't have some settings set in the, the electronics quite right. And we've set we thought we were planning 34 and we planted 10,000 or worst case we planted 76,000. Now what do I do? Oh, so you know those those those problems are, are quickly identified when they run out of seed. And 20 acres instead of 40 acres, but, you know, you know, getting it planted, right. Make sure, you know, two inch depth, I mean, to two inches right now seems fairly deep, but, two inch is really where we need to be at. You know, if the ground's a little bit wet, especially on clay ground, you know, that can cause problems. Can't get the seed seed furrow closed. Good. So, you know, wait until we get the right conditions to plant those. That's really the big key to corn. Getting off to a good start.

[15:36] Tom Barber

And I know you mentioned we were talking a little bit just before we started this on Enlist Corn. And that may be something new that it's out there this year.

[15:44] Jason Kelley

Yeah. They're they're I think Pioneer's got some new Enlist tolerant corn or Enlist corn. So and there may be some other companies, but, what is that? That brings us RoundUp, Liberty. Of course. Enlist. So what, 2,4-D. So what does that bring to us Tom? 

[16:04] Tom Barber

Well and then the fop, too. Yeah. To me the biggest thing for that is maybe I won't get as many calls on your Clincer, Ricestar. Ricestart drift, Provisia drift, that kind of thing. You know, if we use that next door to some fields that we know we're planted in Provisia or no Max Ace or something.

[16:23] Jason Kelley

Yeah, that's what the questions have been that, you know, I can say it's rice friendly corn, but it's, you know, certain things, you know, certain herbicide that does have some tolerance.

[16:34] Tom Barber

And I guess we won't get the Auxin lean like we would if you spray 2,4-D at the regular rate over corn or you know, increased tolerance for later application.

[16:45] Jason Kelley

What about burn down? I mean, you know, if you put in 2,5-D and you're burned down, you get behind, the wind's been blowing, and now all of a sudden you want to plant, can, then go back and look at the label whether.

[16:56] Tom Barber

I would have to look, to be honest with you, but, we've done it. I can tell you. We've done that in research, and, yeah, we haven't had any issue. And in general, I don't I haven't seen much record regular corn on issues with that. But, you know, it's not.

[17:10] Jason Kelley

I think most people in the past hadn’t been using 2,4-D and maybe they wanted to maybe they had pigweed. But in corn there's always been other options we could use that we're safer. But, you know, I've still got some old pictures in my file somewhere that, somebody sprayed some 2,4-D off label. And, you know, about waist tall corn, it's fallen.

[17:30] Tom Barber

Absolutely. So, I mean, I think it brings bring something to the table. We've looked at it, from a weed control standpoint. You know, if you have a heavy flush of morning glories, you know, when the window where we can spray it this little it can help us with that. It can help us with, any horse weed. Not the best horse weed product, but, I mean, they can suppress it. And, again, like Bob said, all we're looking for is a little bit of help and we can out grow it.

[17:59] Bob Scott

10 or 12 ft tall corn can shade out most things besides morning glory.

[18:05] Tom Barber

So, you know, I think it brings it bring some cool tools to the table, brings some protection. And if we've got Johnson grass, you know, and, it's not resistant to the fops, which I don't think that's a lot of widespread out there in the counties, but, you know, we might can use, something to control it. You know, from a fop standpoint. And in that for that process. So controlling Johnson grass and other grasses. But, anyway, what else we need to talk about, Jason, Bob?

[18:38] Jason Kelley

You know, corn Acres I think are going to be up. You know, last year in 2024, we were down a little bit. We had 500,000 acres. And I think part of that was due to price and whether we had some areas of the state that didn't get everything planted, they wanted to. So, previous year we had 750,000. So, I don't know, I think this year we will be up. I don't know if we will hit that 750,000 mark, but, you know, there's a there's a lot of these corn hybrids that are in short supply. You know, I've been doing some calling around looking for, you know, the newest and best. And some of those are long gone. So, you know, I think the demand is there as long as we get the right weather to get it planted. I think a lot of people are going to plant more corn this year than the previous year.

[19:25] Tom Barber

Okay. Well, that's I didn't know because I know it was fluctuating there. In the winter meetings everybody was down on it, the prices were suppressed. 

[19:33] Jason Kelley

Price went up. And then, you know, everybody got a little more excited. So maybe they got some booked locked in and prices you know tariffs and all that. It's went back down a little bit.

[19:42] Tom Barber

We’re not gonna get into that on this podcast, hahaha, we’re not going there. Well all right well we wish and everybody a good safe 2025. And we'll, we try to do these podcast weekly through the growing season especially. And so again, if you have any topics you would like us to cover, you can email, Bob Scott. His information is on the website, hahaha.

[20:11] Bob Scott

So is Tom’s, hahaha.

[20:14] Tom Barber

Or text us if you have our numbers and, we'll be happy to try to cover something, or any questions that y'all have. We mentioned replant. We've got replant and the mp44, the herbicides to burn down. We've got a replant guide that we're trying to update now. We're just adding herbicides to the replant guide. So the information that there is still accurate, we're just adding a few that that aren’t currently, on that guide at this time. So, with that, any final comments as we close out?

[20:47] Bob Scott

Well, we talked a little bit about drift and the corn from the rice. There is a table, in there that gets referenced a lot. That is sensitivity of crops, to various herbicides. And, that's, that's one of my most often referenced, tables. Guys are worried about doing it. It's in the 20s somewhere in the book. But I would mention that table as well.

[21:12] Tom Barber

Yes. It's on page 28, 28 of the Mp44. Sensitivity of major Arkansas field crops, the commonly used herbicide.

[21:22] Bob Scott

Yeah. And so you'll have to read into that on corn because it just says corn. It doesn't list all the different types of corn that are in there. So there's a lot of Asterix is now not herbicide tolerant crops but.

[21:34] Tom Barber

Well, and that's a very good point because I have walked fields that have been sprayed with glufosniate and we’re not, what does it have to be, Jason, SmartStax?

[21:42] Jason Kelley

Well, yeah. You know pioneer I mean a lot of their a lot of their corn is Roundup, Bt, it’s probably Liberty Link The on the DeKalb side, the SmartStax, you know, needs to be SmartStax if you’re spraying Liberty over it.

[21:56] Bob Scott

Yeah. You know that's a good point. I don't want to speak for Jason on this, but, from a agronomic standpoint, this is not a year to be taking chances or not knowing for sure what field you're in, or if your variety is a good variety for Arkansas or messing with your irrigation. I mean, I think you you need to do things that are going to make you money. It's going to be tight this year. So the most expensive fields are usually the screw ups. Yeah. You know, whatever that may be. You know, where there's herbicide or something else. And so, I think we got to run a tight ship this year, to weather these prices and stuff.

[22:32] Tom Barber

All right. Good. Last comments. Well, anything else? If not, well, thank y'all for joining us on this episode of The Weeds AR Wild podcast on Arkansas Row Crops Radio.

[22:45] 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.