2025 Spring Fertilizer Outlook: What should MN farmers consider, avoid?
Hello, welcome back to University of Minnesota Extension's nutrient management podcast. I'm Jack Wilcox in communications here with Extension. March is almost over, so today is our spring fertilizer outlook. We have four guests with us here today. Can you each give us an introduction?
Fabian Fernandez:Fabian Fernandez, University of Minnesota, nutrient management specialist looking at nitrogen management for corn cropping systems.
Jeff Vetsch:I'm Jeff Vetsch. I'm a research supervisor at the Southern Research and Outreach Center in Waseca. I focus primarily on nitrogen management, but work with p and k and sulfur as well.
Brad Carlson:Brad Carlson. I'm an extension educator. Work out of the regional office in Mankato. Work statewide extensively with nitrogen and water quality issues.
Daniel Kaiser:Daniel Kaiser. I'm a nutrient management specialist. I work statewide, but I'm located out of the Saint Paul campus.
Jack Wilcox:Let's start off generally. Brad Carlson, what are field conditions throughout Minnesota right now?
Brad Carlson:Well, we had our nitrogen college here about a week ago in in, up in Crookston. So I had a chance to drive the state pretty well, all the way up, and I was in Rochester last week. So I've been all the way from the Southeast to the Northwest. And I would say, you know, honestly, things look kinda average. There was water standing when you got way up towards Crookston.
Brad Carlson:There was a number of fields where you did see some of that. I know in my home area, we're seeing some ponding in the low areas. Was that where you normally see some ponding? I'm not sure that the frost is really out yet, so it's really hard to say for sure whether that's a that's a surplus or it just hasn't had the opportunity to drain away. But but from an overall perspective, I think we know it was pretty dry at the end of the year last year.
Brad Carlson:We didn't get a lot of snow. However, we have been getting some you know, there was actually, there was some rainfall around Christmas time, and now we have been getting some snow late. So things, I think, are are more on the dry side in most places, but I I don't think we're quite as dire as it seemed like it was going to be last fall.
Jeff Vetsch:Yeah. Here at the Southern Research and Outreach Center, we've still got light frost in the soil from a depth from about 12 inches down to about 20 inches deep, but the frost is the temperature's right around 32 degrees, so it's not very strong. One good, you know, rain or three or four very warm days could probably take it out. I would agree with Brad's sentiment that I think there's areas of the state in the West Central part that are probably pretty dry. But here in South Central and Southeast, I don't think that's the case.
Jeff Vetsch:We had some decent moisture recharge last fall, and we've had some this year. We've had that wet snow here about three weeks ago, the March. There was, like, 1.6 inches of precip in that, and the majority of it did incur infiltrate into the soil because the soil was not froze, deep at depth. So I think that that moisture is available to move through the profile. We don't have any tile flow yet, but we won't see that until the frost comes out.
Jeff Vetsch:There is some snow here that was received this week in Southeast Minnesota, but I wouldn't expect that to hardly last through the weekend.
Brad Carlson:I think one other point, Jeff, you you kinda brought this up about the the frost in the soil being weak. With it being relatively dry in a lot of the state, the frozen soils are we don't have a lot of ice, a lot of frozen water. And I guess it's worth remembering the physics. It takes a lot more energy to thaw water than it does to heat air. And so if we got frozen soils that aren't particularly wet, that frost tends to go out fairly easily and fairly quickly.
Jack Wilcox:What are some early fertilizer application options that Minnesota growers might want to consider? Fabian Fernandez?
Fabian Fernandez:Yeah. So before we talk about that, I think it's important to kind of be reminded of of what we are looking at. You know, we haven't started the growing season yet, and, the challenge always with nitrogen is knowing what is going to happen during the growing season that can impact nitrogen availability, nitrogen loss. And so when when you look at that, if you're looking at doing an early application of anything with nitrogen, the the two sources that I would suggest that work would be anhydrous ammonia or ESN, polymorphicuria, something that keeps nitrogen from, nitrifying quickly because, as soon as we start warming up, the soils will or the fertilizer will start to nitrify. And and, of course, the challenge is if we get wet again later, we can lose some of that nitrogen that is nitrified.
Fabian Fernandez:So when you look at nitrogen sources, those will be the only two options that I would feel comfortable using this early in the season. Anything else, you have pretty high potential for that to start nitrifying right away. And, of course, when we talk about anhydrous ammonia, soil conditions are critical. If if you are applying in in soils that are very dry or very wet, you have pretty high potential to lose some of that nitrogen through volatilization at the moment of application. The thing that I always recommend to farmers is do a pass, go back, smell.
Fabian Fernandez:If you smell ammonia, you know that you're losing nitrogen. It's probably not a good situation to to be applying. And then when we look at something like ESN, the really important thing here is to make sure that you incorporate that application. Don't leave it on the soil surface because the potential for that to move with water is really high. ESM floats with water.
Fabian Fernandez:I was just thinking, I don't know, it's been, like, four or five years ago that we had, like, 18 inches of snow in late April '1 year, and it all melted in, like, two or three days. It was, there was water running off everywhere. And and if you leave it on the surface, you are going to end up with all that application in the lowest spots in the field or or out of the field into some drainage channel. So those will be the only two options. I would say that that's pretty much it.
Fabian Fernandez:Nothing else at this point. Later in the season, we have other options, of course. And the other thing too that I I would suggest or or recommend to farmers is to kind of look at your options. Corn doesn't really need a lot of nitrogen early on, and so we are always worried that we may not get in time to apply nitrogen. The reality is that once we get the crop planted, there is typically enough of a window there to to apply nitrogen even before the corn emerges, and you're not really going to gain anything other than potentially, of course, the the logistics, you know, of just getting it done.
Fabian Fernandez:But, in in terms of the agronomic aspects of nitrogen, you're not going to gain anything by applying it earlier than than waiting until about planting or even after planting.
Daniel Kaiser:We get years like this, and I was kinda waiting actually for the first question to roll in about early application of urea. So I know, you know, Fabian that came you know, both of us think it was, what, the second week in March from Western Minnesota, people looking at trying to get out and getting an early start on things. And, you know, the big thing about urea is you have to remember is it is highly water soluble itself. So, you know, if we get you know, if the soils are somewhat frozen still, you get some water on top of it, the stuff will dissolve relatively quickly, and it tends to move, pretty readily with wherever the water's going. So, I mean, you're you're talking about essentially concentrating a lot of your nitrogen in areas where the water's collecting, whether that's within or off-site of the field.
Daniel Kaiser:So, I mean, it's pretty common. I think it's pretty common to start looking at getting a start, but it's one of the things I would avoid, you know, particularly with urea. We know that some of the at least the ammonia loss too. I mean, if you can't get it incorporated, that's gonna just kick in right after application. So if the stuff starts to dissolve, I mean, you could lose, you know, ten, fifteen, 20 percent of it, you know, potentially just by through volatility, through the ammonia loss.
Daniel Kaiser:And this isn't a, you know, a nitrification issue with that. I mean, we've seen this, with surface supply. There's some data showing that with surface supply in the winter. So that's where it makes me concerned because we really need to make sure that the, soil underneath, you know, with many of the fertilizer materials, whether it's, you know, PK or these other materials are aren't frozen, so there is some ability for the water to move downward. And, you know, just kinda gut wise, maybe p and k, you know, could be an option or some of the fields.
Daniel Kaiser:It just there is some risk right now, and that's one of the things to watch out for. You know, I'd say maybe Lyme. You know, if you got some of that to go on, it might be good to maybe consider looking at some of that. But it's just kind of a problem right now because we you know, there's gonna be, I think, fair amount of variability, especially early in the season where where there might still be just some of that frost lingering, and that does tend to be an issue that we wanna avoid. I would say just bar none, just make sure that you aren't applying anything on top of snow, at this point.
Daniel Kaiser:Because as rapidly as we can see a lot of that melt, it could be an issue where, you know, again, a lot of these fertilizers being water soluble that they're gonna move wherever the water moves. Know, we really wanna try to keep the the fertilizer where it's applied as much as possible right now.
Fabian Fernandez:One thing that, you reminded as as you were saying something, Dan, you know, I mentioned ESN as an option. One thing to be really careful with ESN, though, is, you know, if it's the first thing that is running through agars and things like that, those tend to be a little rusty right now, and it will wear out the coating that is protecting that nitrogen. So if the coating is compromised, it's cracked or broken because of all the aggression with rust or things like that, you basically are applying urea at that point. And like Dan said, urea is just not a very good option right now. So if you're planning on ESN, make sure that the handling is done correctly so that, you don't end up applying e urea.
Fabian Fernandez:If you wanna do a test of how in you know, the integrity of that coating is, just, you know, grab a handful of of the ESM product, put it in in a jar of water, and then go back twenty four hours later and see how much of that is still there. If it has dissolved, the coating is broken, and you're applying urea. So you should not look at that as a as a good source for for this early in the spring.
Jeff Vetsch:I think one opportunity that, we see more and more small grains in Southeastern Minnesota, and I think with the ten day forecast looking quite positive next week, I could think that, there could be some fertilizer applications and some planting of small grains possibly as soon as the end of next weekend. So that's one area that people could maybe get an early start on.
Jack Wilcox:Dan Kaiser, talk to us about what practices should really be avoided and why.
Daniel Kaiser:Well, you know, and I guess I didn't cover this too. I mean, the thing about, you know, what worries me the most about people with specifically in areas where we have more urea is the fact that, you know, you neglect a lot of the issues with the volatility component of it. And, you know, looking at where that's going to be worst, you know, continuous corn situations where you have a lot of residue is is an area that can really kick start some of that, that volatilization of the and loss of the urea through ammonia. So, you know, that's kind of one of the issues that it's not really as as simple. A lot of people, I think, negate a lot of these.
Daniel Kaiser:The fact that it's spring, that these early applications, it's just more potential for loss. And, you know, I'll go back to, you know, 2024 and, you know, looked like we were gonna get a really good window where we did get a start in April, and then it got wet again. So it it I mean, it's better really on the nitrogen side and to look at applications as close as planting as possible. And just know the fact too, there's there's really no reason to jump the gun because there's plenty of post planting options too if it gets to a point where the stuff has to go in. Especially if you're in a corn following soybean situation, there are options out there that you can use.
Daniel Kaiser:I mean and I know it always boils back to a lot of concern about the from the re on the retailer side really pushing just from the fact that they need to get everything done. And so there's always the, well, you know, we wanna get started because we can't guarantee we're gonna get get to you, and a lot of people, I think, get really concerned about that. But, with some of the inhibitors we have out there, you know, surface applications, they they are an option for what can go on post planting. So if you gotta get the crop in, there are some options to do so. So, I mean, that's really the main thing with that.
Daniel Kaiser:And, I mean, really, the big thing I would avoid too is, UAN right now. You know, I would absolutely not be putting anything down. I mean, I don't know if anybody's carrying it right now, as cold as is, but, you know, one thing with UAN is you're already 25% nitrate. I mean, you've already got quite a bit of, nitrogen there that if we do tend to get a wet situation that could be, flushed out, and you could start seeing some of that through the tile lines. So just be careful on some of these things.
Daniel Kaiser:You know, these early applications, we I expect them. You know, I was, you know, generally, you hit around the March if, we start seeing some bare soil out there. I'm, you know, just kinda waiting for the first question to come in from somebody to ask what they should be thinking about or, you know, they're thinking about maybe getting out there, getting some urea down. You know, is this a good idea? And that's just, you know, I I realize there can be some issues later on if, we do tend to get wet with getting everything done, but there's just a lot of risk right now with that.
Daniel Kaiser:And it usually just, to me, guarantees that you're gonna especially for a retailer, you're gonna have a repeat customer because they're likely gonna be losing nitrogen and have to supplement some later anyway. So if that's the case, you know, delaying probably is your better option, because, you know, maybe you can just save that early trip and just put it all on later.
Fabian Fernandez:One other thing that I would say to avoid is if you're doing, again, nitrogen applications, The areas where we tend to have the most potential for nitrogen loss are areas where it still stays wet. And so low areas in the field where water tends to accumulate, that's that's where you will have the most potential for nitrogen loss. And so avoiding those areas, you know, people often talk about variable rate applications and those kinds of things. I I think that the the biggest advantage of doing variable things in the field is you look at the landscape and look at those areas where you have the potential for nitrogen loss and avoiding those areas, at least now during the early part of the season.
Jack Wilcox:Jeff Vetsch, what have you heard that growers are excited about or hesitant about? What are their attitudes going into 2025 here?
Jeff Vetsch:Well, I think most of the questions that I heard during the winter were looking at nitrogen management options and things. And I think that was kind of in our area was a reaction to the challenges that they had last year. But things that they might be hesitant about, I would say maybe biologicals. I think there's a lot of excitement and interest in that a few year two, three years ago, but it seems like they're a little bit more hesitant on those products, going forward at least in the near term. And then I think that I had a comment that I heard that I thought was interesting.
Jeff Vetsch:One grower said something to the effect of, I've got my n p and k figured out, so now I'm gonna focus on micros. And, you know, in our soils in Minnesota for corn and beans, probably the own and most of our crops, The only micro that's probably of major interest is zinc. And I know Dan's had some recent research in zinc. I did some a few years ago. Actually, it's almost fifteen years ago now, believe it or not.
Jeff Vetsch:And I don't think that those they're big yield responses that can be had there. There might be a few bushels. But, Dan, what are your thoughts?
Daniel Kaiser:Yeah. It doesn't seem like it's fifteen years ago, Jeff, but, you know, it's we've been doing this for quite a while. And, you know, in general, my when I've looked at a lot of the zinc research, it's always boiled down to situations where we've had low soil tests. And some of these widespread applications, particularly with growers with chelated sources with starter, I've always had my doubts, in terms of the overall benefit of of some of those. But I know there there's there's still a fair amount of interest, although I think you're seeing less and less in some of these areas of actually using starter that or they're switching over to maybe the surface dribble using UAN and, an ATS on the soil surface that the in furrow, you know, may not be as much of an option.
Daniel Kaiser:So, you know, I've always kinda gone into that thinking that there isn't a whole lot there. I mean, I do have a, study at Lamberton that we've had in place. I mean, I'm going on, I think, fifteen years with that study right now. The initial, study we started with treated p and k with some biologicals, then I had some biologicals with starter. I mean, the basics of it essentially is I've got broadcast treatments with p and k applications, and then I've got four starter treatments.
Daniel Kaiser:So I'm I'm usually using just a a in furrow starter only, in this case, three eighteen eighteen with or without some additive, which the last few years has been the 9% chelated zinc. And if I look at the data, you know, individually within the years, mean, the zinc's never really impressed me. If you look at the soil test, the soil tests were kind of up near one part per million DTPA, which generally, I don't see much of a benefit. I just went in and I looked at that, and, it is interesting because when I look at the data because these are corn corn soybean rotations. If I just average for every rotation, the corn to two corn years together, then the the zinc treatments were popping out.
Daniel Kaiser:So it makes me rethink this a little bit with that. Although, I mean, these soil tests were probably marginal here, so there might be some benefits. So, I mean, it might be something to think about. I mean, I I just still think widespread across the state that it isn't anything that, you know, it's consistent that, you know, even 50% of the fields are gonna benefit from this. I mean, I think it's still gonna be some isolated circumstances.
Daniel Kaiser:And I think certainly if anybody has manure in their rotations, you know, especially swine manure, I just I just find it really hard to believe because most of time I see the soil tests are, you know, two, three part per million zinc, and you get to that point, I don't think you're gonna see much of a benefit. Just interesting looking at that because it's kind of a low input strategy that we're looking at. That's really what I've been interested in right now are the growers' attitudes towards looking at reductions in rates. Just I'd be interesting to see because I know, Brad, some of that FinBin data, you know, still kinda shows you know, there's still some pretty big differences out there in terms of, fertilization strategies in in kind of least profitable farms?
Brad Carlson:The least profitable farms are spending 30% more on fertilizer than the most profitable farms. And we don't know exactly what that is, but based on the interactions we have with farmers, we can pretty well surmise that it's a lot of either unnecessary products, it's applying too higher rates, it's building soil test beyond high and continuing to apply crop removal rates, even though we're past the high ranges or in the high ranges. There's a lot of that kind of stuff. In general, and Jeff, you kind of talked about kind of the lessening of interest in biologicals. I have sensed with the current economics in agriculture, there really has been kind of a damping down of of interest in in a lot of those types of products that products and technologies, I'll say also some of the variable rate stuff and so forth was being sold like, oh, you're gonna take your operation to the next level with this.
Brad Carlson:You're doing everything perfect and now you're gonna do something more. I think there's been a lot of lowered expectations with a lot of those things that, in general, we're kind of finding that, like for instance, with variable rate, where there's money to be made is by lowering your input costs. It's not necessarily by increasing yields. So the profit potential is not real high. So I've kind of personally, I've kind of detected just an overall lack of enthusiasm for a lot of doing a lot of new and different stuff, this year.
Brad Carlson:I think the one thing though that I have, picked up on, there still is a lot of confusion about inhibitors in nitrogen. I think there's confusion between between nitrification and urease inhibitors. Farmers will just draw out the term, well, I used an inhibitor. And you'll say, well, for nitrification or for urease, they won't even know what you know, they'll say, well, it was such and such product. And it's like, well, okay, that product was intended for your urea to keep it from volatilizing and blowing away in the wind.
Brad Carlson:It doesn't stabilize the nitrogen in the soil and and so forth. But I think the really, the ultimately, probably the bigger challenges that there's been a number of biological products that have advertised themselves to have some of those properties. That's not been well established, you know, and there's getting to be some move afoot with some of the regulators in the state to start requiring the use of inhibitors, for instance, with manure in some situations and so forth. I think this is an area a lot of farmers are just going to need to brush up on. One of the themes that I've hit on previously with a lot of those products is they probably work in terms of the desired effect of nitrification inhibition or urease inhibition, but that doesn't mean they were necessary.
Brad Carlson:Kind of watch with spring applications and nitrification inhibitors, did it really make any difference from from a productivity standpoint? You know, Fabian talked about the places where we have or suspect there will be high loss potential, where you've got, heavy soils, that pond water, sandy soils. I mean, these are areas that are better managed through split application than just applying an inhibitor with your nitrogen. So I think when economics get tight, it's really best to come back to some of the basics of the four R's and and really look at your fields and what they're kinda telling you to do. Don't try and manage it through inputs.
Daniel Kaiser:Some of that stuff you're talking about, Brad. I mean, really, the big thing I would say, if you're looking at these products, is to do a little investigation because, you know, I'm not completely convinced that some of the people that are selling these products really exactly know. They just are looking at the marketing, pamphlets for everything and what they say. I'll you know, an example, I had a, you know, question from researcher here at the university. Some of the growers he works with up north, they were looking at some sort of nano fertilizer.
Daniel Kaiser:I can't remember what's nano code or some sort of coding, for urea. And, you know, if you look at the marketing material on there, it says that it replaces commercial inhibitor sources. And I look at the stuff, I'm like, you know, this doesn't make a lot of sense. Because if you look at what's in there, I mean, there's an anything that's been established to really have some of those desired effects. That's kind of the main thing I think people need to be aware of right now is everybody's looking for that easy source of something to increase their overall efficiency.
Daniel Kaiser:One example another example, I think it was, you know, Jan or it was December '24, January '25. A few consultants talked to me that, you know, some of their growers are looking at this it's a a dry starter fertilizer source that you mix with water that it's it's cheaper a little bit cheaper than ten thirty four o in their standard rate. And it's supposed to have these additives in it to increase P availability in soil. But, you know, if you you know, really, when I start looking at it, if I break down in terms of what they're getting, you know, with the rate they're putting on, you get, like, one or two pounds P2O5 per acre with that application versus if I go with a two and a half gallon rate of 10-34, I'm getting 10. You know?
Daniel Kaiser:So say that's four bucks an acre versus maybe $5 an acre for ten thirty four, or if I'm only getting about 20% of the nutrients, what's the value there? I think the thing that really everybody needs to look at with a lot of these things that get to be marketed as cheaper sources with these special additives in it is, you know, still the crop's gonna take up a certain amount of nutrients. I mean, it's gonna need a certain amount of nutrients. Everybody seems to be really, you know, hell bent on hitting the right removal rate on an annual basis, yet we're looking at all these products essentially if you're applying 20% less. What are you getting out of it?
Daniel Kaiser:That's where when we I look at these fertilizer prices the way they are, particularly with MAP and DAP, you you really gotta look at the value of what you're getting out of it. And that's usually what I look at when, you know, with anything is, you know, what's in there, what's my value per unit nutrient to make a decision on on really what to do with this. You know, I guess maybe I'm old fashioned and, you know, thinking that, you know, I kinda like the more simplistic strategy and making sure you cover yourself with your base fertility program, that you're covered there, and all these other things, I mean, that you're gonna spend a lot of money on a bunch of unproven technology. Is it really worth it to supplement the dollars for those unproven technologies versus your standard fertility program where you know you're gonna make the bulk of your money? You know, with Brad saying, you know, some of with that FinBin data, then it boils down to, you know, situations where you can reduce.
Daniel Kaiser:And, I mean, I think that's the really the decisions that the hard decisions that people are gonna have to make. And it is amazing to me, although I guess I shouldn't be surprised. I talked to some of the independent consultants I know, and, you know, they get a little frustrated at times with coming up with a plan with their growers, but then their growers go to the retailer, and the retailer says, but don't you just need a little bit more? And, like, with P and K, you know, close is good enough. I mean, you don't need to be exact with a lot of this stuff.
Daniel Kaiser:And, you know, then you look at tweaking with all these other things, and you just get to the point where you're just spending so much money. And just the the big thing is just don't neglect that base fertility program. Just make sure that's covered. And if you got some extra money, you got a little extra spending money laying around, you wanna play with some of this stuff, you know, there's nothing wrong with it. But, you know, make sure that you're not undercutting yourself initially where you could be cutting your yield more than than anything and, you know, reducing your overall efficiency.
Fabian Fernandez:You cannot create something from nothing, and that's something that people kind of forget or or they get this idea sold to them that certain product will just magically make nutrients more available, and I will be always really worried about it because it just it it just doesn't work like that. One thing that I wanted to kind of circle back to the you know, in terms of things that I've heard these these winter back to zinc is this thing with phosphorus and zinc, you know, where you have too much phosphorus that you can create that efficient you you can create the zinc deficiency just because of the high phosphorus levels. And while that has been shown, the reality is that the situations where you have a lot of phosphorus in the soil is typically manure fields. And when you apply manure, you're applying a lot of zinc, lot more than the plants will need. So it's really not a concern, but, people kinda pick on these things, and and and they get all worried about it.
Fabian Fernandez:But the reality is that if you have high phosphorus, you likely have a lot of zinc as well. So it's not really an imbalance or an issue there.
Daniel Kaiser:Well, that's one of the things I tell a lot of growers on the zinc side is, I mean, the soil test should be relatively accurate. So if your zinc soil test is, you know, high, say, you know, one and a half, two part per million. I mean, I it's pretty common, I think, for me on some of the nerve fields. Sometimes they'll see three, four, or five part per million that you shouldn't really need it. That that interaction, while we know it's there, typically, where that interaction comes into play, it'd be if I, you know, apply just an insanely high rate of phosphate fertilizer to a field that's already marginal deficient marginally deficient.
Daniel Kaiser:Likely, it'll put it over the edge. You know, these nutrient interaction things, I mean, I it's one of the things you you're hearing a lot of, but it's just really a good way to sell product. You know? Okay. There might be some isolated circumstances.
Daniel Kaiser:But in general, if your soil tests are high enough, you shouldn't really have to worry too much about with the availability. The same goes with these, all these people trying to sell people on putting more potash down to increase their k base saturation. Because, I mean, I look at all my data, and when you start looking at the numbers, you know, I've got k base stats, you know, down close to one, or I've got, you know, some over four, all in situations where I have no response. So it's how much do you wanna spend? I mean, do you wanna spend, you know, thousands of dollars to get a couple bushels per year where you'll never return the cost?
Daniel Kaiser:I mean, that that's the big thing I think a lot of people have to think about is you'll hear these theories out there that make a lot of sense, but you gotta pick through some of this stuff and, you know, just see what's the overall, you know, economic benefit because, you know, yeah, maybe you can pick up a couple bushels here and there, but if you can't cover the cost, you know, it gets to be pretty expensive where you're you're just spending more than inverting more money towards areas in your operation that, you know, you'll likely be spent better elsewhere. There just there aren't any magic cures out there, and that's, you know, everybody has their new product that's supposed to be groundbreaking and do all of these things. But, you know, I can guarantee you that if you look at what's in a lot of these products that they've probably been tested forty years ago, And the products at that point in time came and gone went from the market that there's really nothing special about them now. And, you know, biologicals, I'll be interested to see. You know, Brad, those comments, I mean, I still get a lot of questions from people, but, you know, it's interesting talking to a few people at a meeting.
Daniel Kaiser:You know, I they gave a presentation recently on that. And, you know, a lot of them are more, I think, just interested to learn more about what they are. And, you know, I think it kinda makes your head start to spin in terms of how complicated some of the the the situation is. And it's, you know, any of these additives, it's just amazing on how these things have ballooned and exploded. But, you know, I go back.
Daniel Kaiser:I've been in Minnesota. You know, I started in February my first year was 02/2008. We were working with a lot of phosphorus solubilizers then. And, you know, within about three, four years, I never heard of them again. And now I'm hearing about them again.
Daniel Kaiser:These people are worried about phosphorus and and and fertilizer prices. So, you know, probably three, four years, guess what? They'll probably be gone again. And, you know, wait another ten, fifteen years, they'll probably be back. You're trying to bank on the fact that everybody has short memories to remember that, I mean, you probably tested a lot of these things, and they didn't work, ten, fifteen years ago.
Daniel Kaiser:So the question is why would they work now?
Jack Wilcox:Last spring about this time, nitrogen carryover was kind of a topic, probably not too big a topic this year because of all the precipitation we had during the growing season.
Fabian Fernandez:I would say that we are kind of looking at more of a typical year this year when it comes to residual nitrogen. So I I would not worry too much about it. I mean, of course, if you have a situation where you you are wondering how much residual you have because of fell crop or manure applications or things like that, you can certainly test that. But by and large, I I would imagine this year would be more of a typical year from a residual standpoint.
Jeff Vetsch:Areas in Southern Minnesota, you know, here had a lot of drowned out areas, and there's probably some carryover in some of those spots, but it's gonna be really hard to manage because I'm guessing it's pretty highly variable as you go across there. It'd be kind of an interesting study if somebody wants to do it to go every 25 or 50 feet and take a core across one of those drowned out areas to three feet and see how much residual nitrates in there. But my guess is it kinda it's all over the place. The same thing with those drowned out areas, you know, they probably didn't remove any p or k, so it's possible that there's that there's sufficient p and k in some of those spots because they had no crop removal. But my guess is those fields probably already got it, or they're gonna get it again next year anyway.
Fabian Fernandez:The drowned out areas, you know, the the the thing with that is that, yes, you did not remove nitrogen with the crop. But, you know, with how warm it was and how wet it was into, like, July, this last growing season, a lot of that probably denitrified. And so you end up basically on a wash. There is no, you know, there is not much residual there.
Brad Carlson:You know, Fabian, you mentioned the the locations or situations likely to see a nitrogen carryover, the the long term manure use, whether there was a crop failure and and, particularly corn on corn because we don't need to worry about the soybean side. I guess the point I've made with the pre plant nitrate test is you can take it anywhere if you're so inclined. It's just you're just kinda out your effort and the the cost to do the testing. If you don't find anything, it's nothing. And if you did find something, well, you can credit it.
Brad Carlson:It's just that, we try and target it on the places where you're likely to find something. But, I guess if you really want to, you can go ahead and take the test anywhere you want and just see what you find out.
Jack Wilcox:Educator Brad Carlson, researcher Jeff Vetsch, and nutrient management specialists Dan Kaiser and Fabian Fernandez, all with University of Minnesota Extension. We appreciate you being here.
Jeff Vetsch:Thanks.
Fabian Fernandez:Glad to be here.
Jack Wilcox:Do you have a question about something on your farm? Just send us an email here at nutmgmt@umn.edu. Thanks a lot for listening, and we look forward to seeing you next time.
Jack Wilcox:We'd like to thank the Agricultural Fertilizer Research and Education Council, or AFREC, for supporting the podcast.
