UMN Extension Nutrient Management Podcast

University of Minnesota Nutrient Management Podcast Episode: “Edge of field N and P reduction strategies”
November, 2023

Written transcripts are generated using a combination of speech recognition software and human transcribers, and may contain errors. Please check the corresponding audio before referencing content in print.

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Jack Wilcox:
Welcome back to the University of Minnesota Extension's Nutrient Management podcast. I'm your host, Jack Wilcox, Communications Generalist here, at U of M extension. In this episode, we're talking all about edge of field nitrogen and phosphorus reduction strategies, and we have three panelists here with us today. Can you each give us a quick introduction?

Brad Carlson:
I'm Brad Carlson, an extension educator. I work out of our regional office in Mankato statewide. I work extensively with nitrogen, but particularly, the water quality issues related to nitrogen and, therefore, a fair amount with ag drainage because that tends to be a conduit for the nitrogen getting into water.

Laura Christianson:
Hi, there. I'm Dr. Laura Christensen, relatively new hire at the University of Minnesota, working to update the science assessment that underpins the conservation practices recommended in our Minnesota nutrient loss reduction strategy.

Jeff Strock:
And I'm Jeff Strock, a professor in the Department of Soil, Water, and Climate, but located at the Southwest Research and Outreach Center near Lamberton, and pretty much spent my whole entire career working with farmers on nutrient reduction types of things, nutrient management things, and these edge of field types of practices that we're going to talk about today. So excited to get going with this.

Jack Wilcox:
Let's just start right off; what is an edge of field practice and why is it used?

Laura Christianson:
Our edge of field practices are exactly what they sound like; conservation practices that reduce the amount of nitrogen or phosphorus that we send downstream, and they're located at the edge of the field. A good way to think about them is in contrast to our infield practices that we recommend, like improved fertilizer management, or cover crops, or reduced tillage, those are all infield practices. And the edge of field practices are at the edge of the field catching any extra nitrogen or phosphorus that might go downstream.

Another way to think about edge of field practices is that they're sometimes described as conservation drainage practices. So in our drained landscapes, we have a set of practices that we refer to as conservation drainage practices, and the idea of conservation drainage is allowing your tile drainage system to work in the field as it was designed to meet agronomic production goals, but then also providing environmental benefits at the edge of the field by making sure that we're not sending nitrogen or phosphorus downstream. That's the idea of conservation drainage. And our edge of field practices that we're talking about today fit right into that idea of conservation drainage.

Brad Carlson:
And I think it's worth noting that the state is currently dealing with nitrate issues in both surface and groundwater. Particularly when we think about the surface water issue, we've got the state's nutrient reduction strategy, which was written about 10 years ago, a little less than that, and as part of the overall national effort to reduce hypoxia in the Gulf of Mexico, it was directed by the USEPA, and that set forth a target for 45% reduction in nitrate and surface waters. And so, each state has its own plan and a lot of our research here in Minnesota has indicated that if you're following nitrogen best management practices, it's only about a third of what the nitrogen is that's getting in the water. A lot of it is coming because of the climate issues that we've got, as well as some of the peculiarities of the state and with it being cold and so forth.

And so fertilizer management alone, while it's an important step and particularly, it comes with the caveat that, that's if you're following best management practices, which of course that's the area we need to emphasize there, but that alone, probably, isn't going to solve the problem and so we're looking at a combination of practices. And so for a lot of farmers, they've been engaged in this whole concept of nitrogen management for a long time, but we're probably moving forward in the state as far as getting a little more aggressive with putting some of these edge of field practices in for the sake of addressing some of our water quality issues.

Jeff Strock:
Sure. I think when we start thinking about edge of field practices and why they're used, I think a lot of the way that we, as researchers and extension and trying to work with our partners and state agencies have really tried to think about these types of things is to really think about practices that are, hopefully, going to be a win-win or, at the very least, a neutral win situation. We don't really want to look at practices that are going to, necessarily, possibly, impede the farming operations. So we have this three-legged stool that I like to think about, that thinking about productivity, profitability and being good stewards of the environment.

So a lot of these types of things, as we work on them, we really try to keep those three things in mind so that as we move forward, we can try to address some of the, what's the word I'm trying to think of here? Some of the trade-offs. There can be trade-offs in some of the things that we try to do and not everything is perfect. If there were silver bullets, we'd be using them and we'd be solving these problems to reduce the losses of nutrients downstream, but unfortunately, there aren't any silver bullets and we have to shoot with silver buck shot and try to do the best that we can.

One of the other things that I want to try to remind people of, Jack, is we're going to embark on talking about, some of these things is that we can build structures or design practices at the edges of the field to work, but sometimes, mother nature has a way of exerting her force on these things, and although we can engineer practices to the best of our ability, sometimes mother nature creates scenarios for us that, maybe in really, really wet times, I think about 2019 when it was so, so wet that our practices were functioning and they were doing pretty well, but just the sheer massive volumes of water that we were piping through systems, these practices, they can't treat and remove every last bit of nitrogen or phosphorus.

So sometimes, people need to understand that there are certain things that get thrown our way that mother nature throws at us, that our practices are just not capable of functioning quite at the same level of efficiency as what they're designed for, so.

Brad Carlson:
And I think the other thing that's worth paying attention to, with respect to some of these practices, is some of them do perform multiple functions. In Minnesota, we've got these locally developed watershed plans, and so of course meeting the objectives of the state's nutrient reduction strategy is part of that, but there's other objectives also, particularly where we're looking at flood mitigation. We may be looking at situations where we need to hold water higher on the landscape and keep it out of surface waters altogether that could be part of this. But then, even on the farmer side, there's issues with having adequate outlets. We hear a lot of complaints that, gee, this drainage system was put in by my dad 40 years ago and it worked fine, and now it doesn't. The water's not going away, and so forth.

So there's other things going on, too. There's the need for ongoing maintenance and drainage ditches to keep them working and so on. And so the concept of edge of field practices will go beyond just simply addressing nutrient content of water.

Jeff Strock:
Brad, you actually chimed in on something that struck me that I was in a group that we were having a conversation about this idea of adequate outlets, and try to maintain the drainage systems in a good functioning capacity. And sometimes, different groups, for example, researchers or state agencies or farmers are using terms or defining certain things differently. And I recently was in a group where there was a conversation about adequate outlets, and the definition that that group was using was really not thinking about the tile outlet, itself, as a constraint or a limitation, but thinking about things more downstream and that the constraint may be culvert sizing at road crossings. And so we need to be listening and paying attention to how we're talking about these rather complex, and sometimes tricky, issues dealing with water and nutrients.

Jack Wilcox:
What specific practices do each of you have experience with, and maybe which have the most potential for use in Minnesota?

Jeff Strock:
Some of these things you had a little caveat at the end there about which ones have the most potential. That can be a little bit of a tricky thing at times just because, I think as Brad mentioned, in our more northern climate, things don't always behave when the ground freezes for four to six months out of the year as they do in other locations in the country.

Controlled drainage is a practice where in a drainage system in a field, ordinarily, we try to look at putting in some sort of a field to tile control structure within the system so that we can modify the elevation of the outlet of the main coming out of a field, for example. And ordinarily, in those types of systems with controlled drainage, there is some additional expense, the control structures, there's also some additional expense of narrowing the drain tile spacing, a lot of the times when we do that to try to get a more level drain spacing out there, a little bit flatter drain or a water table.

One of the things that we've seen, and we've published a number of papers on these, when we look at a practice like controlled drainage, there are some limitations. It has to be really quite flat field or the contractors need to be looking at putting these types of things in on the contour, and so there's a little bit more of a nuance to doing that work. But in every year that we've done work with this type of practice, and we had done it for 15 years on a farmer's field in Western Redwood County, we always got water quality benefit to it. Always. In moderate drought conditions, we did see some yield increases. We also had a couple of very wet years during that time, and when management was not as intensive as, maybe, it could have been or should have been, we did see one year where we saw a yield decline because we didn't get rid of the water fast enough under that controlled drainage situation.

So there are some situations where it takes a bit of effort to manage a controlled drainage system when you're using, say, a manually operated system and you can get modest yield increases. We published a paper on this here not too long ago, where the range was 4 to about 11% yield increase under moderate drought conditions. On average, there really wasn't much of a yield increase with controlled drainage, but under those conditions where we had these moderate droughts, we did see a 4 to 11 bushel yield increase. So that was a nice little piece.

Drainage water recycling is a practice where essentially, you could think of this as a farm pond where the outlet of a drainage system can flow into a pond, an impoundment, a reservoir. There's lots of terms you could use to describe that. And then, so as Brad mentioned, this provides a bit of water storage on the landscape, so it has the potential to, maybe, take the peak flow and cut it down. We haven't specifically done research to see what the magnitude of holding that water back is, on say, downstream flooding or peak flows, but anytime we can hold water back, that's a potential bonus.

The other thing that's an additional benefit of doing something like drainage water recycling is from the nutrient standpoint. We can hold any of the dissolved nutrients that are in that water back from going downstream in these little reservoirs, so N & P is held back in the system. The really, really neat potential for drainage water recycling is that there's definitely the opportunity not only for that nutrient reduction component, but also the potential to use that water back on the landscape as supplemental irrigation. We've been doing that work here, in Lamberton, for about seven years. And the first four years that we practiced it, we only ended up needing to add water twice in the first four years. The other two years, 2018, 2019 were obviously really, really wet here, in Minnesota, so we didn't need to pump any water. However, the last three years, 21, 22, 23 have, obviously, been some droughty conditions, and so we've been pumping water back onto some of our research plots to try to look to see what the potential benefit would be of drainage water recycling on crop yields here, in these heavy to medium texture soils.

And so in the data that we've summarized so far, the first year, we saw an 80 bushel to the acre increase where we put on supplemental irrigation to corn. We saw a 40 bushel yield increase in beans that year compared to just the rain fed un-irrigated. The second year, we saw 40 bushel yield increase in corn and a 20 bushel yield increase in the beans. Unfortunately, at this point, I haven't worked up the 2023 data, but I suspect that we'll see some modest increases in yield there, too. So again, controlled drainage, drainage, water recycling, a couple of things that we know definitely have an environmental benefit for reducing and holding nutrients back, and for sure drainage water recycling has definitely shown, year in and year out, when we're actually pumping water and we need it, that we can increase yields by some fairly dramatic numbers.

Laura Christianson:
I want to continue on that theme of controlled drainage, drainage, water recycling, and I think you also mentioned wetlands or constructed wetlands. And to the second part of the question, what practices, what edge of field practices have the most potential for use in Minnesota? When I think about the tile drain landscapes in Minnesota and across the Midwest in a hundred years, the practices that I know that we will be doing include drainage water recycling, and also constructed or restored wetlands.

When I think about the sustainability goals that we have for the future tied with that agronomic production goals, those two practices are really at the forefront for what I'm excited that drainage systems will look like in a hundred years. We all know that managing water successfully is such an important part of even just being able to do agriculture successfully, and so the ability to manage our drainage water with the practices of controlled drainage and with the up and coming practice of drainage, water recycling, those are just really big parts of what I think our future in Minnesota look like, in terms of managing agricultural water.

Now, in the interim, before we get to the 100 years from now, I do also want to talk about some other newer edge of field practices, the practices of denitrifying bioreactors, AKA wood chip bioreactors, as well as the practice of a saturated buffer. And so maybe it's important to define what those two practices are. A wood chip bioreactor is what it sounds like. It's a pit full of wood chips that cleans nitrate out of tile drainage. Now getting a little bit more science-y, inside this pit full of wood chips, there are good bacteria, or natural bacteria that live in the environment, that live on the wood chips, and as nitrate in the tile drainage water goes by them, they clean the nitrate in the water and turn it into harmless nitrogen gas. So these, what they're called as denitrifying bacteria, they are naturally present. They convert nitrate in the water to dye nitrogen gas into gas, which is 78% of our atmosphere. And because it's these bacteria that are cleaning the water inside a wood chip bioreactor, that's why we call it a bioreactor, because it's a biological water cleaning process.

The other practice that I mentioned is the practice of saturated buffers, and as I think many of our listeners know, we have a buffer law in the state of Minnesota, which provides immense benefits for water quality, in terms of reducing the amount of sediment and nutrients in runoff, surface runoff that get to our streams. But a nuance or a challenge with our riparian buffers in a tile drained landscape is that tile pipes underground short circuit all of those great benefits that that riparian buffer or stream buffer are providing. That tile pipe, that tile main, or tile outlet cuts straight through that great riparian buffer underground, and so you're essentially short-circuiting all of the benefits that you receive above ground with the nitrate that is in the tile drainage water.

Enter the practice of a saturated buffer, which is where you cut into that tile main or cut into that outlet, you use, what we call, a control structure or a water control structure. It's really just a check dam underground that routes your tile drainage water to the side into a diversion pipe so that, that pipe can allow your tile drainage water from the field to join the shallow groundwater inside the buffer at the edge of the field, and so you, essentially, reconnect the hydrology at the edge of the field. So again, back to this concept of conservation drainage. You have your tile drainage system working in the field, and then with a saturated buffer, you're allowing that tile drainage water to seep through the buffer soil to allow the soil to naturally remove nitrate that would otherwise shoot straight out to the stream in that tile outlet or tile main.

Jeff Strock:
Here in Minnesota, we've got a couple of different styles. We've worked on one here, at the research center, that's what we call version 2.0. So the trenches that Laura mentioned are great, and we've had a lot of good success with bioreactors. Again, there can be, it's not a perfect system. We can get bypass flow in situations where we have really, really high flow and the capacity of the bioreactors such that it might not be large enough to capture every drop of water from every event that might be flowing through the system, but they are highly, highly effective in removing nitrate and have been shown to be able to remove phosphorus, as well.

One of the other things that we've noticed, and we've had lots of discussions here amongst the researchers and some of the state agencies in Minnesota, is that just because of the wetting and drying of some of the bioreactors, we've seen some subsidence in some of the wood chip materials, so when they become dry, a different type of bacteria, and actually fungi, can get in there and decompose that carbon pretty quickly. So it's something that we're going to have to do as we work through, as Laura was talking about, in terms of implementation that we need to make sure that these are well maintained for the traditional in-field bioreactor.

We've also been working on one, and I know Laura is aware of some of the work we've been doing here, in Minnesota, where we've basically taken and built bioreactors, essentially, above ground to more or less act to be able to be set underneath there. For example, in some situations, say, a tile outlet, and that we add water through the top or through the bottom of a bioreactor in what we call a cube. And we've used corn cobs and wood chips in there, we've done various types of research and we found that it can be these types of things, regardless of the style of the bioreactors, can be really, really effective in reducing nutrients.

One of the challenges that I've been challenged with by some of our colleagues in the state agencies is related to the concept that Brad mentioned a bit earlier, and I'm going to use a slightly different term here, is the other services that we can get, the ecosystem services that we might get from some of these practices, and some of them are a little bit limited. So I know that when we're thinking about the precious dollars that we have to invest in agriculture and cleaning up some of the water, that groups that are supplying the money are probably, maybe, a little bit more interested in practices that have more ecosystem services than fewer. And so, at least right at the moment, our bioreactors are really one dimensional from the perspective of providing a water quality ecosystem service and not a whole bunch of others.

And so we've been trying to think and conceive, some of our colleagues that Laura and I have in a RS, about how do we go about, maybe, improving some of the ecosystem services of some of these types of practices like bioreactors, that maybe they're going to be more pollinator friendly or something like that, that we could provide some additional ecosystem services. So we're not, I guess what I'm driving at here is that even though we're talking about these edge of field practices, don't be mistaken that we're done doing research on them. There are still other questions to be answered, and things that we need to address with all of these types of practices, and some of it relates to coming up with additional ecosystem services from some of these practices to make them more lucrative for not only farmers, but the environment.

One of the other ones that I wanted to spend a little bit of time talking about, which as we look into the not too distant future, and Brad and Laura both talked a little bit about this, is thinking about water storage on the landscape. And as Laura alluded to, constructed wetlands or reconnecting natural wetlands where it makes sense, that's not going to really bother the farming operations too much, are going to be practices that will have some water quality benefits for farming. They'll have some ecosystem service benefits, such as things like habitat and things of that nature.

One of the other areas that we've been doing a fair amount of work over the years here, in Lamberton, is that looking at ways that we can try to manage the water in our drainage ditches and here, in Minnesota, as well as other states, I think of Indiana, Ohio, Iowa, where we've got many, many miles of drainage ditch, it's infrastructure that already exists, and currently the paradigm that we use is, get the water off the landscape as quickly as possible. And there are opportunities to look at some of these drainage ditches just the way that they're currently built. Some of them might be a bit oversized where we could temporarily store water in the drainage ditches to get some temporary storage to delay, say, the peak flows or maybe help impact flooding. We know here, in Lamberton, we've seen pretty dramatic reductions in nitrogen and phosphorus just by managing our drainage ditches with a little bitty check dam like Laura's talking about, only a foot tall, so we're not holding massive amounts of water back, but we're holding small amounts of water back, which allows it more contact with the vegetation in the ditch, the biology that actually exists in the ditch to actually go through for denitrifying some of the nitrogen that's there.

But there are other possibilities if we look into that crystal ball, possibly for things like our ditch research, that we could move forward, and that is that it could also provide a source of water for additional drainage water recycling. So maybe instead of having to build new ponds, we could store some of the water in some of those ditches. Of course, this relates to drainage laws and it gets complicated really, really fast, but we need to be having these conversations and thinking about these types of things as we move forward because of, again, some of the possibilities of ecosystem services and using some of the infrastructure that already exists on the landscape for multiple benefits that would include not just environmental benefit, but also some benefit like irrigation water, supplemental irrigation water for the farmers.

Jack Wilcox:
Are these practices of something a farmer can pursue or do they require local governments to be involved? What's your take on that?

Brad Carlson:
In general, most of these practices are not going to be pursued without somebody else being involved. That really, obviously, depends on the specific practice. Certain things are much more personal. For instance, controlled drainage is just simply on a system by system basis. A farmer certainly could pursue that. You may be able to put in a bioreactor on your own if you choose to do that, possibly a saturated buffer. Although, it's worth noting that there's a lot of design work that goes into these. You probably, you're at least going to need somebody to get involved in designing it. It's not likely that a farmer or probably even a contractor is able to size these things and so forth.

But I think the bigger picture things, when it comes to some of the stuff Jeff talked about, constructed wetlands, particularly some of the things involving ditch management, if we're looking at two stage drainage ditches, if we're looking at potentially retaining water in the landscape, whether it's low dams or something of that sort to just slow water down, that kind of stuff you can't do on your own. We know that we've got a drainage law in Minnesota and we have drainage authorities, and so you can't do a whole lot of stuff that's impacting your neighbors and the entire system unless you got permission to do it.

And so I think that's really the key for farmers, as far as whether they're able to or want to pursue a practice on their own, is really to take a look at, is this completely within the boundaries of my farm? And whether you choose to, for instance, go in and try and get some cost share or something, that's your own deal. However, are you even able to do it? Are you able to legally do it? And those are the bigger questions. And so as soon as it starts impacting the entire system or tile that your neighbors have that's connecting to yours and so forth, I just don't think it's really prudent in a lot of cases to at least go and start having some conversations with the drainage authority, your county ditch inspector, or your soil water conservation district, those kinds of folks, and make sure that everybody's on the same page.

Jeff Strock:
Yeah. One other thing to add on to what Brad was talking about, too, here, is things like, for example, our personal experiences with drainage water recycling. Here, in Lamberton, we've already had ponds in existence, so we didn't have to build anything. Our site that we have in Western Redwood County, we had a site built specifically for doing drainage water recycling. And Brad, I'm glad you mentioned what you did, because essentially, the permitting process that we had to go through took us probably almost a year and a half to get the permits and everything laid out in order to even be able to build that reservoir for drainage water recycling on farm.

So there's things that, like you said, that take planning and you need some professionals involved, especially when it comes to design, and I suspect that, maybe, Laura has some experience with some of that design type of thing from her past, as well.

Laura Christianson:
Yeah, and on that note, the NRCS, as conservation partners, are pretty critical in this conversation, too. The practices of bioreactors and saturated buffers are both accepted standard practices within the NRCS tool book of practices, and so the NRCS is just a real critical partner in this conservation conversation.

Brad Carlson:
I think the other thing that we need to keep in mind is these practices are, in most cases, there's going to be certain ones that work well in certain parts of the state and not in others. Controlled drainage requires the field to be relatively flat or it gets really expensive. There's parts of the state where we have a lot of opportunity to construct wetlands or to rejuvenate existing wetlands by running water into them. However, for instance, the southeastern part of the state is not characterized by naturally occurring surface waters, so those things wouldn't really happen there. However, those tend to be really nice landscapes for doing saturated buffers. There are opportunities for bioreactors in that part of the state and so forth. And so some of these things are also going to be fairly regional in nature. From an individual farmer's perspective, you just simply need to understand what's likely in your toolkit and what's not in your toolkit, based on your farm and where you live in the state.

Jack Wilcox:
Is there any assistance available for farmers who are interested in one of these practices?

Brad Carlson:
Yeah, so historically, a lot of the funding does come from USDA, and so I think most farmers are pretty much up to speed on how that whole process works. One of the problems with that, historically, is how much money's available, and frequently, they'll score the practice and rate you against other people and look for who's getting the most bang for their buck for the money spent. Or sometimes you're required to address multiple concerns. You can't just go in and do the single thing you want to do, you got to do all this other stuff also. That can get to be a hangup. However, in Minnesota, fortunately, we have a fairly decent sized pool of money that comes from the state to work on the priorities that are set forth in the watershed plans, and so that assistance is getting much more readily available.

I guess it should be noted that we've had a backlog of lots of people who wanted to do lots of stuff that there just wasn't cost share available for, that's been getting paid for by a lot of that money. But that backlog is being cleared, and so a lot of the watershed groups now are able to look more at their priorities and target that money towards the things that are going to accomplish their goals and spend less of that having to deal with farmer so-and-so has had all these sediment basins they've wanted for years and they just couldn't get the funding for it. That stuff's getting cleared up.

But I think the other thing, and this has been talked about a fair amount, is just simply technical assistance. Most of these practices are relatively complicated, in terms of their design, especially when it comes to sizing them. And so, I mentioned the fact that a farmer could do it. Yeah, technically you could. Technically, you could build your own septic system, too, but it's not going to pass muster until somebody comes and checks the thing out and says, this met all legal requirements. Similarly to some of this kind of stuff, you could do it yourself, but you probably need to do an awful lot of studying before you actually could come up with a design that functions. And so that's really probably the key is to just simply be talking to people that are resources.

One of the things that I think we don't take full advantage of, oftentimes, in Minnesota is the extent to which we have free advice for this kind of stuff. Your soil water conservation district is a point to walk in the door, and they can put you in touch with a engineer. There are engineers who are assigned to regions in the state who can answer a lot of just your general questions to start with before they get really specific on actually preparing designs and help you sort through whether this is something that's going to happen.

I think the other thing is, well, there's really, there's two more points I want to make. One is farmers tend to be reluctant to do a lot of stuff that doesn't involve making profit, because if you start doing things that don't make you a profit, you can be out of business. We know that ag cycles, and so you get a couple bad years where you're not making any money and you spend a lot of money on stuff that didn't pay you back, that can turn into trouble. And so in the case of a lot of these practices, they're intended to have environmental outcomes.

Jeff did talk a little bit about some things that could increase yields, but in general, a lot of these practices, what you're really looking at doing is having a positive environmental impact and then just not negatively impacting your yields, and so the yields stay the same. And so typically, we are looking at trying to find a way to cover the cost of this stuff and then reap the environmental benefits. So that's probably the big thing when it comes to getting assistance with this. The other thing is, obviously when it starts involving more than one individual, it is extremely difficult for a group of farmers to, for instance, pursue constructing a wetland when it's crossing two or three property lines. That, it just begs for getting somebody involved on the local level who can get everybody on the same page and look for how that's going to all be accomplished.

Jack Wilcox:
Are there any last words from the group?

Laura Christianson:
Yeah, I will just highlight that while we're talking about the edge of field practices today, and we certainly love some of our edge of field practices. Bioreactors is a favorite of mine. But I want to highlight that it will take all of the practices, all of the conservation practices in our toolbox to make significant headway towards meeting our nitrogen and phosphorus loss reduction goals, and it'll take all of the practices implemented at a very high level across our landscape in Minnesota. And so whatever practice works for you, I ask that you consider it, visit with your local soil and water conservation district. Just start the conversation today. We appreciate your help.

Brad Carlson:
And a lot of these practices in Minnesota, they are out there for the sake of they're being tried and they're being demonstrated, but they are not widespread. And so some of our survey data, for instance, that nitrogen smart indicates farmers have heard of this stuff, but very few people have ever actually tried it. I'm going to throw out the fact that with the state's nutrient reduction strategy, you will be going beyond just hearing this stuff. People will be coming and asking if you are interested and willing to put some of these things on your farm. So I think it's valuable for every farmer to get themselves up to speed on these practices so that when the time comes, they can decide if things are right for them.

Jack Wilcox:
That about does it here for this episode of the Nutrient Management Podcast. We'd like to thank the Agricultural Fertilizer Research and Education Council, or AFREC, for supporting the podcast. Thanks for listening.

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