Weeds

(Jim) Good morning folks. Welcome to That’s My Farm. I’m Jim Shroyer, your host and we’re in luck because we’re in Riley County and we’re going to be talking with Dr. Curtis Thompson, our Weed Extension Specialist about corn and sorghum herbicides and what’s new. You’re going to want to take notes. Get your piece of paper and pencil and we’ll be right back after these words from our sponsor.Closed Captioning Brought to you by Ag Promo Source. Together we grow. Learn more at agpromosource.com.

(Jim) Good morning folks, welcome to That’s My Farm. I’m Jim Shroyer, your host and we’re in luck because we’re on the campus of Kansas State University at the Agronomy Farm. We are fortunate to have Dr. Curtis Thompson with us. He is our Weed Scientist, Extension Specialist. And Curt, thanks for being here and it’s time to be talking corn, grain sorghum herbicides. What do some producers, corn producers first, what do they need to be thinking about at this time of year, prior to planting? (Curtis) Always a pleasure to be with you Jim. (Jim) Thanks Curt. (Curtis) For corn folks, right out of the chute I’m saying, have you taken care of your Marestail? (Jim) Right. And a lot of times of course, we have recommended Fall application and that hasn’t happened. We want to get after this Marestail very shortly because once Marestail starts to bolt… (Jim) Out of that rosette. (Curtis) …out of that rosette, it becomes increasingly difficult. To be honest with you, the larger that rosette gets, the more difficult it is to control. A reasonably simple fix ahead of corn, throwing in eight ounces of Dicamba or Banvel of some sort. If you have annual grasses out there, throw some Glyphosate in the mix and get things cleaned up. Now there is potential to also add some Atrazine for residual control and you know what that can help us out with is as we move in to April depending on how warm we get, the Pigweeds might start coming and having some residual product in place might benefit…(Jim) Like Atrazine. (Curtis) …like Atrazine can benefit that as well. (Jim) What about in the western part of the state, what do producers need to be thinking about? (Curtis) Of course in the western part of the state, our major weeds– we have a couple of ’em, one is Palmer Amaranth and the other is Kochia. Now Kochia is a very early germinating weed. (Jim) Right. (Curtis) We actually saw a few Kochia plants coming up in late February. To be honest with you, I’m hoping that the corn guys already have some herbicides in place that they put on, either it could have been November, December, January or February. If they haven’t done it now, they’re probably going to be dealing with Kochia post emergence. (Jim) Right. (Curtis) We have put out a lot of different experiments on Kochia at this stage of the ball game when it’s up and growing and even quite small, and haven’t necessarily been successful as I think we should be regardless of the chemistry that we have used. Like I said, I am hoping they’ve got something out early. (Jim) Curt, hang on a second. We have to take a break here. You folks at home hang on as well, we’ll be right back after these words from our sponsors.

(Jim) Welcome back to That’s My Farm. I’m Jim Shroyer. With us we have Dr. Curtis Thompson. And Curt didn’t run off during the break and I’m glad you didn’t either at home. Curt, we were talking about little issues in corn with Kochia and Marestail and Pigweed. Let’s talk a little bit about sorghum. (Curtis) Alright. (Jim) This is going to be real short, huh? (Curtis) This is going to be a little shorter because we talked about, from the standpoint of Marestail, we need to get our eight ounces of Dicamba out. It’s ditto… (Jim) Ditto on what we said. (Curtis) …on sorghum, alright? (Jim) What we said for corn. Now is there a time frame? (Curtis) It’s the same time. Corn is planted earlier than grain sorghum generally. (Jim) Is there a time frame? Or do we have to go by the size of the weed and not necessarily the calendar? (Curtis) For Marestail, it absolutely is the size of the weed and so that’s why we need to be getting after Marestail, whether it is ahead of corn, whether it’s ahead of sorghum or whether it’s ahead of soybeans. (Jim) Right, right. (Curtis) If they haven’t done anything up to this point, those rosettes are sitting in there now maybe an inch in diameter and we need to get after them. (Jim) OK Curt, what about Kochia and Palmer Amaranth in sorghum? (Curtis) OK. You know with sorghum, kind of like we talked… (Jim) …with corn. (Curtis) …with corn, Atrazine and Dicamba type of product, hopefully they have that down early. We’ve seen that do an excellent job holding Kochia in to May. The other concern of course, is Palmer Amaranth and all of the Glyphosate resistant Palmer Amaranth that we’re dealing with. Because sorghum is planted later, there is a window in there that Dicamba, Atrazine is going to run out. We really need to have something in place early May to keep that Palmer Amaranth from coming up. I’m assuming that the Atrazine, Dicamba that was put down early is going to hold, up to about the first of May. And then we need to have perhaps a pre-emergence product that they might use in sorghum, put down in early May or at least a part of it. (Jim) You’re saying before planting them? (Curtis) Well before planting. (Jim) OK. So this is different than with corn because you put down the pre-emerge at corn planting time, which is earlier. (Curtis) That’s correct. But if you’re not planting your sorghum til the third week of May, there might be a lot of Palmer Amaranth that does come up. That can be a problem in managing that if it’s Glyphosate resistant. (Jim) We don’t want to give it a head start. (Curtis) That’s right. (Jim) I can see where that can be quite a problem. (Curtis) It can be a problem. Right. Now we can, if they have had some small Pigweed come up, we can use products like a Sharpen Atrazine, Verdict Atrazine, as a pre-plant burn down. But again, we want to have those Pigweeds small in order for that to work effectively. That can work ahead of grain sorghum. (Jim) Curt, we’ve got to take a break. Folks, stay with us, we’ll be right back after these words from our sponsors. See you then.

(Jim) Welcome back to That’s My Farm. I’m Jim Shroyer and with us we have Dr. Curt Thompson. Curtis, we’ve talked about some old chemistry in some of the weed control that we’ve had so far. I do know there are new products coming out. Enlighten us on some of the new products for corn and sorghum. (Curtis) OK. Actually when we start looking at new products… (Jim) New names, maybe? (Curtis) In many cases some of the active ingredients have been around for some time, but it is a different combination or different ratio. In some cases they may bring some different things to the picture. One new chemistry that came out from Syngenta does have a new chemistry in it. That is Acuron. (Jim) Acuron? (Curtis) Acuron. (Jim) OK. (Curtis) That is basically their Lumax, plus another HPPD inhibitor, bicyclopyrone. The Lumax already is a pre mix of S-metolachlor, atrazine and callisto. Callisto is the HPPD inhibitor. But by putting the bicyclopyrone into the mix we see that Acuron has perhaps a little more activity on some of the large seeded, broadleaf weeds. You will see a little better control of things like Velvetleaf, Morning Glory, Giant Ragweed, Common Cocklebur, those types of weeds where if you just used a straight Lumax, you may see some of those large seeded weeds slipping through. It does have a nice fit. (Jim) Statewide? (Curtis) Statewide and the price of Acuron is at a very competitive level with Lumax. In fact, I think growers can use that two and a half quart rate cheaper than they can the Lumax rate. (Jim) I’ll be darn. (Curtis) I’ve been telling farmers if you have the choice of Acuron or Lumax use Acuron. That is for corn only. That is not a sorghum product. (Jim) OK. I was going to ask you that. (Curtis) Yes. Lumax is both corn and sorghum, but Acuron is only corn. (Jim) Right, right and there’s no pH problems? (Curtis) We always have a little more activity on higher pH’s anytime we have these HPPD inhibitors and the Atrazine. That just means we get a little more weed control under some higher pH situations. Now there are issues if you get too light a soil. Sandy soils, we could have some problems. (Jim) OK. What else? What is new? (Curtis) That basically is the new chemistry. Now everything else is maybe some tweaks. For example Bayer has their DiFlexx. DiFlexx is basically a clarity with a safener. It’s the same safener that they have in their Balance Flexx or in their Corvus and so it actually safens the Banvel component both pre-emergence and post-emergence. (Jim) That’s good. (Curtis) When we use Dicamba in corn we can see all that goose necking. (Jim) Right. (Curtis) Like BASF status, when you spray it on, corn’s got good tolerance. (Jim) OK good. Let’s hold on right there, we’ve got to take a break. Folks, you stay with us. We’ll be right back after these words from our sponsors.

(Jim) Welcome back to That’s My Farm. Curt let’s jump right in to continuing the line of conversation on new products. (Curtis) Alright. Bayer has, in addition to their DiFlexx, they have DiFlexx Duo, which is simply a combination of the DiFlexx and Laudis. And so again, broad spectrum broad leaf weed control and some grass activity from the Laudis. Dow has a new one called Resicore. Resicore, if you’re familiar with their SureStart II or Monsanto’s TripleFLEX II, the Resicore has instead of the Python in it it has Callisto. It is a pre-mix of the Stinger or Clopyralid, Acetochlor and the Callisto. So again, three modes of action, a good pre-emergent and has post-activity in corn. One more would be BASF’s Armezon PRO. We’re leaning toward extended residuals when we spray post emergents. Armezon of course, is a HPPD inhibitor and the Pro part is an addition of Outlook to the mix to extend the residual control of Palmer Amaranth and annual grasses like crab grass. (Jim) Now, which of these products can we, you’ve mentioned a time or two corn, but which of these products can go on sorghum, of these new ones? (Curtis) I’m afraid there isn’t any of those products at this point. And sorghum, brand new products, that list is really, really short. We’ll talk about one of those. (Jim) OK. Hang on. We’ll talk about that after this break. So, folks stay with us. We’ll be right back after these words from our sponsors.

(Jim) Welcome back to That’s My Farm and with us we still have Dr. Curt Thompson and Curt, a while ago you teased us with something new in sorghum. So, I gotta bite. What is it? (Curtis) Alright. We’ve actually been working on this project for some time here at K-State and that is our ALS resistant grain sorghum. Now, we’re soon to be in the market Inzen sorghum, as soon as we get some hybrids available because just a couple, three weeks ago, we did get a registration for the active ingredient nicosulfuron, which is the chemistry that we will use post-emergence in Inzen sorghum to control annual grasses. That just isn’t something that we’ve had in grain sorghum. (Jim) No, grasses are the big problem with Inzen sorghum. (Curtis) They are and so with post emergence nicosulfuron, we’ll be able to control a number of those annual grasses. But they have to keep in mind that it’s not Glyphosate. Think back in the corn days when we were using Accent, we had to spray grasses small if we wanted effective control and there’s some differences between the grass species and how large they can get. But just a rule of thumb is, if you never let these grasses get more than two inches tall, you’re going to have a chance at getting them controlled. They clearly will help out with things like Volunteer Wheat, Barnyardgrass, Crabgrass, Witchgrass, Fall Panicum. Some that we struggle with just a little bit is that darn Crabgrass. Crabgrass does have to be very small if you want to get effective control. We have some other grasses like Stinkgrass that is also very difficult to manage and one that I know from the standpoint of the western two-thirds of this state, Grassysandbur is another one that has to be really small if we expect to get good control. (Jim) So now it’s all contact. It’s not a residual or does it have some residual activity, I don’t remember. (Curtis) The residual is going to be really short, OK? (Jim) OK. (Curtis) We are depending primarily on post-emergence activity. Now it may have a short residual, but it’s not very lengthy. (Jim) OK, so if you get a little bit of a rain later on or something like that you could have another flush of these grasses that would come on and that you wouldn’t be able to control then. (Curtis) Unfortunately yes. But the thing that we are strongly encouraging is that they use a pre-emergence herbicide… (Jim) Right. (Curtis) …in place and so if some grasses come up this would allow you to come in and kill those when you get that rain for that other flush, you might be activating your pre-emergence herbicide and so you’re in business. (Jim) Curt, how big or tall can the sorghum be? (Curtis) They are encouraging its use with Atrazine, so whatever is most limiting on the label when you make your applications, we’re looking at 12-inch grain sorghum. What’s most important is the fact that we get it on small weeds. We are still going to have to control our broadleaf weeds. Again, we’re going to go back to needing that pre-emergence herbicide in place to manage Palmer Amaranth. (Jim) Curt, thank you for taking time this morning to talk to us about herbicides and corn and sorghum and what’s new. Folks, thanks for being with us and don’t forget next time about this same time on Friday morning we’ll have another issue of That’s My Farm. See you then.

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