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[00:00:00] Mike Howell: The Dirt with me, Mike Howell, an ekonomics podcast where I present the down and dirty agronomic science to help grow crops and bottom lines. Inspired by ekonomics.com farming’s go-to informational resource. I’m here to break down the latest crop nutrition research use, and issues helping farmers make better business decisions through actionable insights. Let’s dig in.
Hello again, everyone. Welcome back to the Dirt. Glad you’re tuning in. This week we’ve got an exciting topic for us Today. We’re gonna be talking about nitrogen loss and discussing the differences between nitrogen loss in the Canadian prairies and the southeastern part of the United States where I’m at.
To help me do this, we’ve got my good friend Ray Dowbenko with us. Ray, welcome to the Dirt.
[00:00:59] Ray Dowbenko: Hey Mike, thanks. Great to be here and happy that you asked and I’ll do my best to use my Canadian accent for you.
[00:01:05] Mike Howell: Well, Ray, we spent the last few days in Canada. We were there for the stampede and doing a lot of recording things about Western Canada.
This is gonna be a continuation of that series, and I thought it would be good to talk a little bit about nitrogen loss and what y’all are worried about up there in the prairies. But before we do that, if you would kind of introduce yourself to our listeners that may not know who you are.
[00:01:25] Ray Dowbenko: Sure thing, Mike. Happy to do that. I’m Ray Dowbenko. I had a former career as a senior agronomist with what is now Nutrien. I was working for a number of its pre companies. I finished my graduate work at University of Manitoba in 1989 and went right into the fertilizer industry. I’ve lived in Saskatchewan in different parts of Alberta.
I started out my career in field research, research and extension grono. And then moved into various roles of agronomy, like most senior agronomists, so new product development, market support, market research, generally teaching and explaining to people issues about soil fertility and crop nutrition. And I finished up my career several years ago.
I’ve been doing a little bit of dabbling in the consulting world, mentoring a few graduate students, and just generally hanging out now and getting a chance to talk to old buddies like you.
[00:02:12] Mike Howell: Well, Ray, we’re glad you came on today and I can’t think of anybody that’s got more experience in the Canadian prairies than you, and especially when we talk about nitrogen, you did a lot of work with nitrogen over your career.
Let’s dive right in and start talking about nitrogen and nitrogen loss. And I guess before we talk about loss, let’s kind of identify what sources of nitrogen are primarily used there in the prairies, where you are and why they choose those sources.
[00:02:36] Ray Dowbenko: Well, typically, Mike, back in the day, we had a lot more in hydro ammonia used fall applied a little bit in the spring.
In the last several decades, there’s been more of a movement to urea. So granular, 46% nitrogen urea has been the currency of nitrogen, if you will, and such as it is in the world. We do also use ammonium sulfate 21 or 24 0 0 2 4, and we also have a small amount of UAN urea ammonium nitrate, 28% that gets used, but they’re more in the minority.
I think the majority of nitrogen use is urea, followed by. Probably anhydrous ammonia to a lesser extent, an ammonium sulfate, if we wanna count that as a nitrogen fertilizer rather than a sulfur fertilizer.
[00:03:19] Mike Howell: Well, Ray, that’s kind of totally opposite of how we are here in the southeast. I’ll throw out a little trivia.
Mississippi State University, one of its experiment stations, was a place that the anhydrous ammonia was first applied to a row crop that was done in cotton many years ago, but we’ve talked about that a little bit on some previous episodes. We used anhydrous ammonia a good bit, but we have totally gotten away from anhydrous ammonia down here.
I can’t think of anybody that’s applying any anhydrous. 30 years ago, like you were talking, we applied a lot of ammonium nitrate and a lot of people would still love to be applying ammonium nitrate. We just can’t get our hands on that anymore. Here’s where the difference comes in. Most of our people around here are putting out the UAN solutions like you talked about.
I would say that’s by far our most preferred method of application, and then that’s probably gonna be followed by the urea and ammonium sulfate. There’s a lot of reasons for this. You know, each of these has their benefits as well as their disadvantages, but why aren’t the people there in the prairies using the urea predominantly now?
[00:04:18] Ray Dowbenko: Decades ago, we had a lot more in Hydrous ammonia used, and there still is in certain parts of the prairie, certainly in Manitoba, northern part of Alberta, northern part of Scotch, and more of the more regular moisture areas with heavier textured soils. And there’s a lot of fall application just. Before freeze up.
But as time goes on, there’s different issues around ammonia. And usually it’s the older fellows that have been using ammonia and the younger fellows moving into the farm operations are more comfortable with urea. And it’s also the issue of availability in terms of purchasing on farm storage, that type of thing.
And then there’s equipment uptake or equipment maintenance on ammonia can be fairly expensive to be in PMO business. That’s an ongoing cost. So there’s been different reasons and certainly, you know, people are concerned with. Health and environment issues, safety issues, storage, that type of thing. So I’m not saying it’s going away.
We’re always gonna have ammonia ’cause we need ammonia to make other nitrogen fertilizers. But on the farm it does have the issue that has been moving more to granular dry type products.
[00:05:16] Mike Howell: Well, Ray, we know we have different nitrogen loss mechanisms and we’ve talked a lot about those over the years on the dirt here, but.
Each one of these nitrogen products has its own form of nitrogen loss. So what are growers up in the prairies doing to manage this nitrogen loss? Let’s talk specifically about urea first, since you said that’s the predominant source. Now, how are they managing nitrogen loss?
[00:05:37] Ray Dowbenko: Well, sure. Mike, I’m gonna, I guess toss out two things as a good agronomist.
I’m gonna have to use the word depends at some point. ’cause it can be situationally specific and environmentally predicated, but also have to talk about four R nutrient stewardship and the source rate, time and place. And so to answer the question at the high level, most people using urea are gonna be either applying it in the fall subsurface band, hopefully.
Or they’re me applying it in the spring, again, in soil, in a band or in the sea row, or off to the side, in the side band. Something that keeps it within the soil to preclude the loss to the atmosphere. We don’t see an awful lot of surface applied urea, and when we do, then people are typically using some type of inhibitor, either a single or a dual inhibitor, preferably if they’re going out in the fall, they’re using a dual inhibitor to preclude both volatile loss.
And the issue of denitrification. So we wanna preserve that nitrogen in the fall in pneumonia form as long as we can going into the spring. And even in the spring, if we have surface applied urea, they’re gonna be looking at using an inhibitor to preclude volatile loss and also to potentially reduce nitrate leaching if they’re on a lighter textured soil in a more regular rainfall area.
So. The urea. If we are gonna be applying it, we typically wanna see it in the ground. And if we have to, for whatever reason, surface, apply it without incorporation, we’re gonna promote the use of an inhibitor of some sort.
[00:07:00] Mike Howell: Right. And Ray, that makes perfect sense. Anytime we’re using urea down here, we’re going to have an inhibitor on it.
And most of the time our urea is not getting incorporated with our heat and humidity. We really have to be concerned about volatilization or ization, as you Canadians would say. We have to make sure we have an inhibitor on that. And because of that, that’s the reason we use so much UAN. People can inject this UAN.
We don’t have to do a lot of tillage to incorporate the UAN. We can just put that out with a single shank or a Colter rig and get that injected and hopefully we can prevent that nitrogen loss with that.
[00:07:35] Ray Dowbenko: Similar situation here with our liquid applicators, UAN, if we’re side dressing corn in some of the areas in Manitoba, they will get the injection, as you say, and hopefully the injection is deep enough.
But we do get some growers that are going at regular, I guess, relatively higher speeds. They’re not necessarily getting the depth of an injection that they require. And we’ve seen some shallow applications of UAN with some significant volatile losses and so. If we’re not getting deeper than two and a half or so inches and we’re not getting a ceiling of that injection zone, we’re seeing significant volatile losses and we are recommending an inhibitor even though there is an injection of the liquid UAM
[00:08:16] Mike Howell: Ray, another thing you mentioned was fall application of urea. Now, if we considered a fall application of urea where I was at, they would block us up. Send us to the insane asylum. I mean, there’s absolutely no way we can do that. We just have two warmer conditions. During the winter, we would lose 100% of any nitrogen we tried to apply in the fall.
Talk a little bit about how you can apply nitrogen in the fall in the Canadian prairies.
[00:08:40] Ray Dowbenko: We tend to counsel growers and retailers to wait until the soil’s getting below 10 degrees Celsius, 50 degrees Fahrenheit before they even think about applying. Once that temperature is reached in the zone or the depth of incorporation, we would suggest that they can go out with anhydrous ammonia first in two weeks or so after that, go out with urea in a band situation.
There are growers who will go out earlier than that for whatever reason in terms of size of acres. Uh, before fall freeze up, we could be telling people to wait for the ground to get closer to freezing up or cooler temperatures, and all of a sudden we get snow in the ground freezes and they get locked out of a fall application season.
So they don’t want take that risk. They will go out a little bit earlier and they will use the dual inhibitors or. We do get a lot of people using ESN controlled release nitrogen in the fall, a very good product that’s gonna carry that nitrogen in a protected envelope, if you will, all the way into the spring.
So it depends on the area. For people who are fall applying nitrogen, we probably would be recommending ammonia first if they have access to it, if they’re comfortable. But if they’re gonna use urea, we still look at using some type of inhibitor or a controlled release product for that fall application, ideally is what we’re gonna wanna do to protect that nitrogen.
And then of course, you always. Run up against that idea of, well, there’s an added cost to so many cents per pound. And then they’re gonna ask, well, what are my losses between fall and spring? And typically we can say fall loss may be nothing depending upon the situation, but maybe as much as 20%. And so every situation becomes.
A different conversation with a grower, and it’s difficult to make a blanket recommendation for the prairies because we do have varying soil zones, varying soil types, and what works in Southern Alberta. Where I am is not necessarily gonna work in Southern Manitoba or Northern Saskatchewan or Northern Alberta.
We do need to have better discussions with the growers. Part of the extension education perspective is we need to have crop consultants, retailers, well-trained, and explaining these situations to the grower and asking the right questions.
[00:10:47] Mike Howell: I couldn’t agree more, right? We need to take advantage of these agronomists, whether they’re at the retail location or somebody with the university or a private consultant.
Agronomists can really help you out and help you make more informed decisions about this nitrogen loss. Ray, another thing that we do quite often here in the southeast is we make. Multiple applications of nitrogen. We’ll put some out at planning. We’ll come back and, and make a side dress or a top dress application, trying to time that application when the crop’s going to need it, and also help prevent losing some of that nitrogen.
I know things are a little different in your region and we compress everything into a tighter time window. There. Is split application something that y’all use at all or is it one application and done with that?
[00:11:29] Ray Dowbenko: Well we do. And just before I answer this question, for full disclosure, I’ve been down to your area and I still on Saturday mornings watch the Mississippi Crop Doctors.
’cause I love listening to that show. And I’m hearing them talk about side dressing, corn up to tassel, all the way from V six, V four, V eight, like making four to five applications. And to what you just said is Canadian. I’m going like. No, we’re not doing that. If we’re on eastern side of Canada, we do see a lot more split applications, but where I’m at, when I did field research back in the early nineties, we compared all at planting or all at seeding with split applications.
And the only reason we would go with split applications is if we’re trying to influence protein with a later in season application of nitrogen. Or more often than not because we’re in a moisture challenged area of Western Canada, we’re. Looking at putting on 60 to 70% of our crop requirement for nitrogen at seeding or at planting.
And then if we get the rainfall or we’re gonna get the rainfall, that other 30 or 40% goes out. If it doesn’t rain, we’re saving ourselves on that nitrogen expense. And if it does rain, we get the equipment ready to go. And it’s either gonna be, as you say, a split application with urea or with UAM, depending upon the retail and the farmer’s preference.
So it’s a little different from us. You’re looking at it from. Removal of loss in the system and we’re looking at it solely at as a, do we need this or are we just wasting our money by putting it out there?
[00:12:58] Mike Howell: Ray, I kind of chuckled when you said challenged with the moisture. We were challenged with our moisture this year as well.
We had the wettest May on record, followed up with a really wet June. I’m not sure if that ended up being a record or not, but we had significant nitrogen loss and some of the guys had put out nitrogen at planning and were planning to come back with a lay by application, but it was just so wet along. Of those applications had to be delayed.
Heard about some people flying it on with a drone and just trying to do anything they could to get nitrogen out there. It’s kind of a catch 22. If you run into a situation like this, do you put it out early and hope it stays there, or do you wait on the split and then get rained out and can’t get back in the field?
It’s just a bad situation for our corn all the way around this year.
[00:13:40] Ray Dowbenko: It’s a bad situation, but to me that’s a really good learning opportunity for a retailer and a grower. If they think that’s only gonna happen once in a while and it’s a one-off, okay, but if they think they’re getting more and more situations where they’re at risk of not getting that additional nitrogen on, whether it’s the second or third split, I would seriously want them to have a consideration of a controlled release product like ESN, where it all goes on upfront.
You’ve got that controlled release throughout the growing season based on temperature and. Moisture and you don’t have to worry about that additional struggle to get the equipment out in the field because the weather’s not cooperating. Plus you don’t have that extra cost of whatever, eight or $12 an acre to run a rig out there in season.
So I think that’s a prime opportunity for people to start thinking about not only their nitrogen application method, but they’re nitrogen source and they can still use urea, but they’ve got a protected source that they could use that would. Be something I think that precludes that issue of not being able to get out there.
’cause if you’re trying to side dress corn two or three times and you get out one out of those three and you’re losing 40 or 50 bushels of corn because you couldn’t get your additional nitrogen out there, that’s a big hit to take.
[00:14:50] Mike Howell: Even if you’re not gonna do a huge percentage of it in controlled release fertilizer, like ESN, if you put down a little bit of it that way, that just buys you a little more time to help you get by some of those weather conditions until you can get back out in the field.
That part of it is there and it’s gonna be protected and give you a little more time to make that application.
[00:15:09] Ray Dowbenko: That’s a great point, Mike. I think people most often, and I’m guilty of it in this just past few minutes, of making a comment about using a controlled release product like ESN. Most people think it’s an all or none, but it certainly isn’t.
It can be, uh, any kind of ratio that you need to fit that situation that you’re trying to address. So it’s a good point.
[00:15:28] Mike Howell: Ray, we started off talking that this was part of our series and I was spent several days in Alberta here recently, but the day I flew in, I got to my hotel about 10 o’clock that night, was trying to get ready for bed.
I got to noticing it’s still daylight outside. I had realized this a few years ago. It really brought it back to the forefront, but 11 o’clock at night, you could still see a little bit of daylight. It wasn’t pitch black dark. The next morning, about a quarter to five, I was awoken by the sunlight coming back through my window.
It’s a little bit early for the sun to be coming up. We only had a few hours of darkness there. Now, if it was at home, we would be getting roughly 12 hours of daylight, 12 hours of darkness this time of year. How does the photo period affect how the crops are grown up there in those northern latitudes, and does this have any impact on when we make nitrogen applications?
It seems like we would be trying to grow this crop in a much quicker time. Frame and we would need more of those, not just nitrogen, more of those nutrients available earlier in the growing season.
[00:16:26] Ray Dowbenko: Yeah, it’s interesting perspective. I’m not a crop physiologist, but to the point about the daylight, when you go to Northern Alberta, for example, and.
When you go to Northern Saskatchewan, but when you go farther north in Saskatchewan, you get outta the agricultural production zone. But you can go extremely far north in Alberta and it’s not just Grand Prairie and Peace River, but people can look at La Crete and you’re like a few hours away from the Northwest Territories and you get.
Sunlight, like the land of the midnight sun, it’s like very long days. So now you’re calm about photo period. You got short day and long day plants that make the switch from vegetative to reproductive stage based on daylight. And you think with what you just said about we get all this daylight, well, why can’t we grow soybeans here?
I mean, we got sunlight. The issue, Mike, is we don’t get the heat. We get a short growing season. We don’t have a lot of frost-free days. If we look at growing degree days or corn heat accumulation units, we can’t grow corn north of where I am. We grow silage corn and we grow some sweet corn south of me, but.
We don’t get the heat further north. So Central Alberta and North we get the daylight. You move things through vegetative stage to reproductive stage fairly quickly, which is good because we’re gonna get frost. We get frost sometimes August 12th. So the daylight helps us move the crop stages more quickly.
But it. Make the yield any better than what it normally can be with the type of heat and the moisture that we get. But I like what you’re saying, and I tried to do that once in a greenhouse. We grew corn under 24 hour sunlight and it died because it needs to have a dark period. Right? So we do need some dark period, but no, we get the daylight, but we don’t always get the heat.
The daylight helps move, as you say, through the crop growth stages more quickly. But that’s a benefit to us because we don’t have a very long frost free period. We’ve had snow in every month of the year where I live, but typically we expect on the prairies getting a frost between August 14th and August 18th happens.
We don’t like it, obviously, but it does happen and we’d like to dearly get our corn out of the ground by the end of September of October, but it doesn’t always happen as well.
[00:18:36] Mike Howell: Ray the middle of August. I couldn’t imagine having a frost in. I know some football players that are out there practicing for football at that time.
They would sure love for those temperatures to come down then, but that seems to be our hottest time of the year. Ray, we’ve talked an awful lot about nitrogen and nitrogen management today. Is there anything else that we’ve missed that we may need to cover before we sign off today?
[00:18:57] Ray Dowbenko: I don’t think so, Mike. I mean, you’ve had a lot of series of people on the podcast. A lot of brilliant people, longtime researchers, people that have contributed well, and some younger folks that are contributing now will continue to do that for the foreseeable future. I think the only thing I would like to leave the audience with is that there is a.
Whole host of resources out there. And for somebody like Mike and for Nutrien that are providing you access to these people that have this experience to research, most of these people wanna share it. And the resources are out there. I think growers and retailers should never hesitate to pick up the phone or email or get involved with some of these people.
The people are doing this because they want to contribute. And so I just wanna say thanks, Mike, to the work that you do, and thanks to Nutrien for making this available to the folks out there.
[00:19:43] Mike Howell: Ray, we really appreciate those kind words and thank you once again for being a guest on today and helping us work through this nitrogen management situation.
Listeners, we appreciate you tuning in and if you’ll hang around for just a few moments, we’ll be right back with segment two. Farming Isn’t Farming without questions, and now there’s a place to go for answers. At ekonomics, an entire team of agronomists is waiting and ready to help for free. No question is too big or too small.
Visit Nutrien-ekonomics.com and submit your question with the ask an agronomist feature.
Listeners welcome back for segment two, where we talk to one of our agronomists and ask a question. This week we’ve got Alan Blaylock back in the studio with us. Alan, welcome back to the dirt.
[00:20:31] Alan Blaylock: Thanks, Mike. It’s always a pleasure to be on with you and participate in some of that discussion. We talked about many interesting things.
[00:20:38] Mike Howell: Alan, this week’s question has to do with a topic that we’ve talked about a good bit, enhanced efficiency fertilizers. The question is, how do these enhanced efficiency fertilizers support environmental sustainability and for our nutrient stewardship? Before you get into answering that question, maybe it’d be a good refresher to give a quick definition of what we mean by enhanced efficiency fertilizers, and then get into answering that question.
[00:21:01] Alan Blaylock: Yeah, Mike. The definition of those products kind of tells us how they help us with environmental sustainability. An enhanced efficiency fertilizer is simply defined as a fertilizer material that’s been modified in some way to improve plant availability of the nutrient and to reduce losses of that nutrient.
To the environment, and there are a variety of mechanisms by which this may take place, and especially when we’re talking about nitrogen materials, we’re talking about materials that somehow reduce the potential for loss of nitrogen to the environment, whether it’s preventing leaching loss or preventing volatilization as ammonia or preventing denitrification and the gas losses that come out.
These are the fertilizers that we’re talking about. How do they. Improve environmental sustainability? Well, they’re basically altering some of the transformations within the nitrogen cycle. Nitrogen has various potential points where it can be lost. Nitrate is very mobile in the soil, can be moved out of the root zone with water.
Nitrate can also de nitrify or convert back to one of several nitrogen gases that then can escape from the soil into the air. And some of these are greenhouse gases that we’re concerned about, or nitrogen can be ized from the ammonium form on the soil surface. If it’s exposed to the air, particularly in the conversion of urea to ammonium, we can lose some.
Gaseous ammonia. The way these fertilizers work is typically slowing down some of those processes, perhaps reducing the concentration of one of those susceptible forms. Or in the case of some of our slow release fertilizers, which is one of those mechanisms, we release the nitrogen slowly into the soil and thereby we reduce the exposure of nitrogen to specific loss events.
If we’re releasing it slowly over a period of time, only a small amount is exposed. At any point in time, if I get a big rainfall event, I have less of that nitrogen that’s actually exposed, and the rest is still in the fertilizer granule. Now, some of the other materials we have, we call them stabilizers or their chemical inhibitors, that affect some of these different biological processes.
For example, slowing the conversion of urea. To ammonium that can reduce volatilization loss. Give us a little more time to get that urea into the soil with rain or irrigation or mechanical incorporation so that when the urea transforms, the ammonia is trapped in the soil. Those are called rease inhibitors, or we might use something called a nitrofication inhibitor to slow the conversion of ammonium nitrogen.
To nitrate, and because nitrate is mobile and susceptible to some of these loss mechanisms, that can be an advantage. Ammonium is more stable in its exchangeable cation. It is less susceptible to leaching, and so conserving the nitrogen in that form a bit longer again reduces the exposure of the nitrate form to those loss mechanisms.
We’re basically using these fertilizer materials, additives, or modifications to the fertilizer to alter the rate of the transformations of nitrogen to some of the forms that are susceptible to loss, and thereby reduce exposure and reduce the risk of loss. That helps us be more environmentally sustainable by keeping more of that nitrogen in the soil, allowing the plant more time to take up the nitrogen, getting more of it in the crop.
We call that improved nitrogen use efficiency. If we get more of it into the crop, we’re enhancing the efficiency of the fertilizer. These are the ways that these enhanced efficiency nitrogen fertilizers improve environmental sustainability. They do that by reducing the exposure of nitrate forms to losses out of the soil.
[00:24:43] Mike Howell: Alan, we appreciate you giving us this information on these enhanced efficiency products. Listeners, if you have any more questions about anything we’ve talked about today, please visit our website. That’s Nutrien-ekonomics.com. Until next time, this has been Mike Howell with the Dirt.
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