The Holy Trinity of Soil Health, with Dr. Chuck Rice, University Distinguished Professor of Soil Microbiology at Kansas State University

Dr. Chuck Rice has been an expert in the field of sustainable agriculture for years.

And his work on soil nutrients and farm productivity has changed our understanding of the way that growers conduct their operations.

So in this episode, Tom and Sally dig deep with Dr. Chuck Rice, University Distinguished Professor of Soil Microbiology at Kansas State University, on some of the biggest breakthroughs they've made over the years. And then, he outlines what he calls the "Holy Trinity" of soil health and how growers can harness these elements to build a more resilient operation.

Plus, Tom and Sally outline why every step in sustainability needs to happen in a "Whole Acre Solutions" context.

Episode Transcript

Chuck Rice: It's not one single product or one single strategy. There's multiple strategies, so that makes it more difficult to prescribe, but it also gives more opportunities for the farmer to decide what best fits their operation.

Dusty Weis: Welcome to The Future Faster, a sustainable agriculture podcast by [Nutrien Ag Solutions 00:00:25] . With our very own Tom Daniel, director of Retail Sustainable Ag, and Dr. Sally Flis, senior manager sustainability field. This is your opportunity to learn about the next horizon in sustainable agriculture for growers, for partners, and for the planet. To us it's not about changing what's always worked, it's about continuing to do the little things that make a big impact. On this week's episode, Dr. Chuck Rice, university distinguished professor, soil microbiology at Kansas State University joins us to elaborate on what he calls "The Soil Trinity," his way of explaining and measuring soil health. A long time respected authority in the field, we'll discuss how his work on nitrogen [inaudible 00:01:04] management has shaped our understanding of the science behind sustainable agriculture. But, if you haven't yet make sure you're subscribed to this podcast in your favorite app, also make sure you follow Nutrien Ag Solutions on Facebook and Instagram. I'm Dusty Weis, and it's time once again to introduce Tom Daniel and Sally Flis. And Tom, you and Sally have mentioned before whole acre solutions in previous episodes. And I was thinking the other day, it might be good to level set and just have you describe what exactly a whole acre solution is?

Tom Daniel: Yeah. So, most guys think about an agronomic solution around the farming operation. They think around the cash crop, Dusty. So, they think about the crop inputs, all the things I'm going to need, and strictly focusing on the cash crop. But, when we're talking in sustainability, we talk about a whole acre, how do we treat that acre 365 days a year? Because, the practices that we apply to that acre, not just with the cash crop, but when the crop has already been harvested, we're trying to recognize those things that we can actually influence when the cash crop's not on the field. So, when we talk about a whole acre solution, we're talking about managing the acre 365 days a year. So, during the cash crop time, we take a look at all the different inputs and the things that we want to incorporate on a cash crop, specifically in sustainability, we're looking at things that lead toward an environmental or a sustainable outcome.

Which could be nitrogen management, it could be a soil sequestered carbon, it could be phosphate optimization, there's all kinds of different mechanisms or things we may want to measure that are part of a cash crop. So, we usually start that planting process right about now, or even before now, where we're looking at our 2022 crop needs and what we're going to need for that full solution. And we're testing a lot of those different things that we want to look at. We're looking at a lot of things around nitrogen management right now, and phosphate and fertilizer optimization. And we're looking at a lot of things around the sequestered carbon. So, we manage the cash crop part of the year. And then we look at the non-cash crop part of the year where we're managing that acre 365 days. And Sally, you've done a lot of work this year, we've all done a lot of work, but you've done a lot of work and looked at some of the data right now. We've got a lot of pilots out that we're actually testing some of these different whole acre solutions, as we call them, for the year.

Sally Flis: Yeah. So, if we look across our end to end pilot with the growers we've got there, we've really had to take into account a lot of different variables on these farms. So, we've got dairy growers that have a forage crop, followed by a corn silage, maybe a corn grain, and then you got to figure in manure applications. And what's interesting is how do we fit into that not just the other solution pieces, but the measurements we need. So, we've got to be aware of everything that's going on on that field to figure out when and how do we take soil samples. What's the moisture of that soil? When is the crop coming off? When are they putting on a manure application? So, that the data we're gathering is the most accurate and we're getting the best samples we can. In addition to how do we manage that whole system to optimize crop production and these other outcomes that we want to see coming off the landscape. For example, we've got some growers that are doing the nitrogen management piece of this protocols in the work that we're doing this year, where they're incorporating a couple of different [Loveland 00:04:37] products, they're incorporating in nitrification inhibitor, or a slow controlled release product.

I think we've got one grower that used ESN and the nitrification inhibitor product. But then, they're rolling into a cover crop. And so, what did they need to do to make that cover crop successful? So, it's really, like you say, you got to be thinking about what's happening in that field 365 days year to make these different practices work. And then, on our side from the analytical data collection side, we need to know what's happening in that field 365 days a year so that we get the most accurate information and the best estimate of the outcomes.

Tom Daniel: Yeah. And Sally, I would say one of the key components to think about here too is that as you went through your whole description of some of these different pilots that you're working with, all of them are localized. Someone said the other day, "Can't you just give me a prescription for sustainability that I can just run with over a whole geography?" And the answer to that's, "No," because all of these whole acre solutions are solutions we're working with the growers are basically grower focused and localized, because each field and each farm are going to be entirely different. And you will even find that one grower may be running two or three different type of solutions on his farm based upon whatever outcomes he's trying to get to. So, Sally, I would say it's really different as we travel this country and see the different geographies from livestock management, all the way to managing cash crops and all kinds of different cash crops, all these solutions become really local.

Sally Flis: Yeah. So Tom, we've talking about how this is a 365 day a year thing and doing some ongoing evaluation of performance in the field. What are some things that you would be looking at on your own farm, or as you talk to some of the growers that we're involved with, at this time of year, in this particular season to think about what's the next step on that field or how to plan for next year?

Tom Daniel: So, if I'm looking at my farm, for instance, the use of cover crops and those type of things would be one of the first things that I'd want to look at. Now, cover crops this time of year have already been planted, or they should have already been planted. We've got to start thinking within that solution, we've got the termination of that cover crop. Now we're going to get rid of it when we get ready to plant our cash crop in the spring. So, I'm probably looking at the termination issues that I need to look at. They need to get to a certain height. I'm looking at all those different things. And then, I'm even looking at my startup for my next cash crop. Do I need to look at infer fertility? Some type of starter program to help if I were of a cool wet soil because of cover crop? Or do I want to take a look at insecticides? Maybe I'll need some type of insecticide application to handle some early pests. But, all of those different components should be in a full plan. That whole acre solution is something that's not [inaudible 00:07:35] out through the season, it's something that's determined it early in the crop planning process. And then, it's just tweaked as the season goes along, depending on what mother nature gives us.

Sally Flis: Very true. And, I think, one other thing that's really background of this year's whole acre solution planning is some of the supply chain dynamics we're working with. So we've got consultants and growers that we're talking with right now about projects for next year that are saying, they're planning on making some practice, or rate reduction, changes, but it's really because they're concerned about supply. So, there's a lot of different things feeding into those decisions. We get into conversations with some of the outside partners, or other consumers who just want to know, "Isn't it just a simple decision for a grower to decide to reduce nitrogen application rates and make a practice change?" And the reality is that nitrogen management decision at this point in time goes all the way back to the production of fertilizer.

Tom Daniel: Absolutely. And look a sign of the times right now. We've got a lot of growers, as you said a minute ago, are looking at reduced rates of nitrogen to produce a crop for next year. Not because they're specifically trying to get to a better nitrogen use efficiency, it's just the cost of nitrogen today. It's at an all time high, petroleum prices are high. And growers are going to be looking at efficiency opportunities in the field. So, a lot of the whole acre solutions that we're talking about right now are including a lot of optimization type discussions around nitrogen, phosphate, whatever it may be, trying to make sure that we're controlling those inputs that are going out there to give us the best opportunity for a profit come close at 2022.

Sally Flis: And just to tie that back in, if you're in a situation where you're thinking about, or you know you're going to be making those types of practice changes anyways, now is a great time to be talking to your crop consultant, your Nutrien Ag Solutions staff, or representatives, about how can you potentially earn a little bit of extra, or develop some of these certified credits, around practice changes that you're making that are additional, that are new practices on your farm. But, you're making because of other market factors doesn't mean we shouldn't get those recorded to be reported on this year.

Tom Daniel: Right. And one other thing around a whole life for solution too, is helping our growers reduce some risk. And we talk about risk of supply right now. A good crop plan right now with looking at all the inputs needed for that particular acre and including your cover crops for next fall, those type of planning processes help your nutrient representative be sure that they can make sure you have those products available. When you're looking for them. Worst case scenario, you don't want to be found without a product at the time you need to terminate a cover crop, for instance. You need to be sure that all of that's in some type of whole acre solution with your nutrient representative.

Dusty Weis: And as we've talked about whole acre solutions Tom and Sally, certainly I hear a few themes that keep coming up data, and science, and research, being among them. And coming up after the break here, we're going to talk to someone who has been on the cutting edge of all of these things from the academic perspective, Dr. Chuck Rice at KSU. That's in a moment here on The Future Faster. This is The Future Faster, a sustainable agriculture podcast by Nutrien Ag Solutions. I'm Dusty Weis along with Tom Daniel and Sally Flis. And we're joined now by Dr. Chuck Rice, distinguished professor, soil microbiology at Kansas State University. Dr. Rice, thank you for joining us.

Chuck Rice: Yes. It's great to join you.

Dusty Weis: So, Dr. Rice, you've had a decorated career in agriculture studies, and to get this conversation kicked off, can you describe how sustainability in agriculture has evolved throughout your career?

Chuck Rice: Yeah, that's a great question. And, I guess, I got a long history to see the evolution. So, when I first started in this business, we were looking at productivity and how to become more efficient with nutrients, avoid nitrogen loss, mostly from a productivity standpoint. Then things became more concerning when the environment, we were looking at water leaching, our nitrogen loss by denurification, or gases losses, mostly from the lens of efficiency of nitrogen fertilizer. And then, climate change become apparent. Then we were looking at carbon sequestration, nitrogen as a greenhouse gas, and now we're kind of in the era of soil health and how can we improve soils to be more resilient to climate change, how it can help with productivity, supply nitrogen. So, it's changed quite a bit over that period of time.

Sally Flis: Chuck, do you feel like this is more of the same or we're really getting into different practices, and programs, and solutions, than when you were first looking at just nutrient use efficiency and yield?

Chuck Rice: It's looking from a different lens in some aspect, nitrogen efficiency or nutrient efficiency, you could argue we're doing the same thing. But, it is through a different lens. It's looking at productivity along with ecosystem services, with sustainability, and a much bigger picture, really looking at the whole system. And that's definitely changed the way I thought, the way I conduct research. And we can talk a little bit more about that later. But, it's looking at what a farmer does day to day. He or she is looking at not just nitrogen, or just at corn variety, it's really putting the package together and how it relates to the weather, to the economics. I guess in a science research perspective, we're probably advancing to the farmer level.

Sally Flis: I like that idea. I often push back when we're having discussions or we often touch on discussions of a lot of these programs that we deal with out there are pushing single practices. Just do cover crops, just do no-till. So, it's great to hear that transition of research into more of that holistic systems level thinking, because what we've seen is as you implement single practices, you're changing all kind kinds of different parts of these biological systems. So, as you've worked in soil health, we talked to our employees, and our grower customers, a lot about soil health. How do you define soil health, and what are some measurements that you like to look at as you think about soil health?

Chuck Rice: Yeah. So, there's lots of different definitions. I won't go through the official definition, or two, or three, official definition. But, I think, of it as a way to improve the quality of the soil so that we are more resilient production system, and also sustainable, or more efficient, with the water and the nutrients. Part of my research has been on the native prairie. And so, I have the advantage in that some of the aspects of the prairie, which is very resilient, it's extremely water efficient, obviously it's nutrient efficient, and climate resilient. How can we take the elements of that native prairie and apply them to ag systems? So, what, I guess, I've been known for is what I call The Holy Trinity of soil health and there's three aspects. So carbon is the first step. And carbon's important because... Again, I'm a microbiologist. So, carbon is the food for the microbes.

So, by having more carbon in the soil, then you're going to have more micro activity and that's going to affect nutrient availability and efficiency. But then, the carbon also helps build soil structure. We use aggregation as a metric, but you could talk about water infiltration. But, the neat thing that why it's a trinity is that carbon feeds the microbes, microbes through activity, [fungal high fee 00:15:41] help build aggregates that builds the structure, allows for better water infiltration, capture that, and also stores carbon. So, they're tightly interlinked. And so, what we're trying to measure is then those three aspects. Now the chemists could say, "You should measure pH you should measure this and that." But, really from my standpoint, those three things are critical.

Tom Daniel: So Chuck, I noticed that you've had some recent papers written on the impacts of practices around nitrogen management [inaudible 00:16:10] the changes in relation to nitrous oxide emissions. Any key learnings that you picked up from some of that research?

Chuck Rice: Sure. Early on it goes back to one of the first questions, but when we first started doing work on no-till systems, we saw that no-till had increased N2O emissions. I was at this meeting that I'm at now, we've got 32 years of no-till with fertilizer and compost added, and we're seeing a change in the soil system. As you get better porosity, better aggregate distribution, we're now seeing that no-till in nitrogen management that we're seeing the same or less nitrogen emissions from no-till systems than with conventional till. So, that's been important observation and it's really that long term research. We're seeing a change in soil dynamics. The other thing is that we've done work now in, I guess, the four R's or the five R's, however you want to characterize it, but in tilled systems and early no-till placement is important, timing is important. But, no-till allows you to, I guess, maybe accentuate those four R's. Placement becomes even more important. Timing becomes even more important. So, that now if no-till is the same amount or less into emissions, we can further push the system to become even more efficient and reduce those gas losses.

Tom Daniel: Chuck, I would say too, we talked about the four R's when we're talking about no-till, but even the use of the right fertility or nutritional product is probably going to be a big thing to look at when we start looking at how we're applying some of these different fertilizers to the acre. We not only need to be concerned about the delivery system when we're looking at no-till. It does change the overall concept of everything we look at, even down to the point of what is the right source, what is the right type type of product I should be using with a no-till system.

Chuck Rice: Yeah. So, different sources are important. Some are going to have more losses, particularly volatilization as ammonia. So, urea and hydrus is really key. But, I think, the opportunity is now is if we get the price right, can we use some slow release products that would help extend the time when the plant needs that nitrogen? And that's, again, really important. It's a substitute or another way to get the timing right. And so, the important thing, it's not one single product or one single strategy, there's multiple strategy. That's the good news and bad news. So, you can't say, "Do this thing," and it's going to work everywhere. There's multiple strategies. So, that makes it more difficult to prescribe, but it also gives more opportunities for the farmer to decide what best fits their operations. Whether it's surface applied, or timing, or injection, or dribble, there's lots of different options that fits their operation.

Tom Daniel: Yeah. And it gives a lot of choices to the grower, as you said. And as we've said from the start, all of these things come down to the capabilities and the technologies that are available to a particular grower. So, one solution may work one place, but it won't work everywhere. And as we've said, from the start, everything we do is localized all the way down to the farm level. So, multiple different opportunities and multiple different sourcings allow the grower to make a decision that works for him.

Sally Flis: Chuck, you mentioned that project was a 32 year project, that makes it even harder for us to help growers make the best decision in the field when it takes that much time to really see how that system is going to develop. But, why is it so important to keep measuring a project over a long time span like that?

Chuck Rice: So, a farmer is changing their practices, changing their soil environment. We've been doing this no-till now for 30 years. And if we would've done just a three year study, like I said, we were seeing these change in the soil environment. So, what we expected to see after year three and now after year 30, the dynamics have changed. We've built up organic matter, so now that we're getting differences in nitrogen availability, and that's what a farmer would see. I'm working with a couple farmers in Kansas. One is: He's been no-tilling with cover crops, his organic matter is now 6%. Where a lot of our, I guess, conventional farmers are looking in the 1%, 2% range. He's changed his system. Different micro productivity, nitrogen availability. And so, that's the values long term experiments is, if we were to start it now, we wouldn't have that knowledge to help that farmer that's been doing these high intensity cover crops, working under the excellent soil conditions at 6% organic matter.

Sally Flis: How does a 6% organic matter in a managed system compare to some of the places you're looking at native prairie organic matter, just thinking about what we hear on the sustainability side of getting back more native prairie. Not that that's a bad thing. But, when we're really intensively managing a system and can get up to organic matters as high as 6%, how does that compare? What have you seen comparison to that native prairie?

Chuck Rice: So, that 6% is at the surface. So, it's higher than the native prairie in Kansas. Now, if you're in Illinois, it's maybe close to that. But, for Kansas local conditions, he's above that. So, his farming system is continuing to evolve. And so, now he wants to know how can he take advantage of that organic matter, that nitrogen, and adjust his end rates, but he doesn't want to mine it either. Yeah. He's in a different world. And again, that's why the research is important. The other thing though, what he's doing, and he's changing his system even now, he's now looking at perennials in the rotation. So, he's going to go to annual crops for five or six years. And now he's, actually last year, just planted a perennial mix. And he's going to graze that. Now he's integrating livestock back into that system, and he's going to let it go perennial for three or four years and then go back into annual crops.

Why that is important is that he's changed his fertility organic matter, his physical structure, in the surface, six inches, 12 inches. But, with the advantage of that perennial system, now he can rebuild nutrients deeper down to make it even more productive, which is more like the prairie. So, a lot of the changes that we've seen has been mostly in the top six, 12 inches. But, adding that perennial in that rotation is getting more like the native state that you have that whole profile. Which is really important, because as we see the weather changes, weather, variability, these drought cycles, we need a better profile for water for root distribution to help us work our ways through that drought. And then, when we have these intense rainstorm events, we have these six inch rainstorm events, then that water's going to penetrate and then can conserve in that soil profile to help support the annual crop.

Sally Flis: It is quite a system to think about from top to bottom, how all these different changes really impact things. You think about a place like Kansas where you're worried about replenishing aquifers. And as we tie all these things together, that's really what we're building in these systems is that resilience, not just for that individual field and grower, but really for, at some point, old whole type scales.

Tom Daniel: Let's talk about the fact that we're not talking about single practice changes on most farms. Some of the terminologies that I've had to become used to like life cycle analysis and all those type things. Those create me heartburn in most cases, but you guys got it figured out. I'm just a single agronomist out here in the field most of the time. But, I was taught something way back early that each and every action has a equal or opposite reaction. So, we make changes on the farm and expect to make positive success maybe in one place. But, every time we do something, we create a change somewhere else in the cycle. So, how important is it for us to understand that we need to look at changes we make on the farm more holistically around the full life cycle.

Chuck Rice: So, I'll give you a couple examples. One is that, we just finished a paper that we did analysis of long term no-till studies globally. And what we saw was that when you implement no-till, then you also conserve water. And so, what we saw globally in all these 80, 90 studies was if you're only single cropping, no-till, it's a missed opportunity, because you have the extra water, it allows you now to double crop, it allows you to add legumes in the system. You can do that with a tilled system, but because of the timing you got to till after the harvest and then replant the crop, you've lost your moisture. You've also lost 10 days or so, which can be really critical. And what we saw with the no till is that because that water savings, and the timeliness to plant, then you can double crop, and then you can make more effective use of the water and the nutrients.

And so, it's that systematic approach. That's the advantage. Again, I'm a [inaudible 00:26:00] of no-till, but it's looking at that opportunities. And can you then push the system by adding compost or doing these rotation systems. On the bad news or [inaudible 00:26:11] case is that what we've seen is that with conventional till we were worried about phosphorous sediment loss. And so, no-till captures or reduces that sediment loss. But, now it raised a issue. We got water soluble, phosphorus running off. And so, the question is, "Which is worse? Is it that sediment phosphorus loss, or that soluble phosphorus going off into the rivers and streams?" So, you fix one problem and you created another one. But however, I guess, my challenge is then we got to quit thinking at a single field. Can we manage the landscape? You're not going to have zero emission coming off that field, whether it's gas or runoff. Can you then start working on edge of the field practices to help solve the water soluble nutrients going off, create buffer strips, or other things that we can do to look at a landscape approach rather than a single field.

So, that system is not only internal on that field, but now unfortunately, or because it's more complex, then we have to go much more at the landscape, which then means we have to bring in other disciplines, engineers, ecologists, to look at those issues.

Sally Flis: Chuck, we talked about a 32 year long research project that you've been involved in. What is your favorite project that you've worked on through your career? You've had a lot of projects and a lot of interactions with individuals. What really stands out to you as a favorite from that career?

Chuck Rice: Oh gee. Yeah. I don't know if there's one favorite. The research keeps me going, excited, and passionate. I guess I would point to a couple things. One is: Working on the prairie, it's given me a different perspective and, and how I can apply those prairie principles to ag systems. The other one that's ongoing right now is really the soil health partnership where we're doing some research on these metrics that I mentioned, but the fun thing is, and the challenging thing is, that we're working on farmer's fields. So, we're working on large strips, 40 acre plots in that sense. And it's a joy to see some of the research being applied, but it's also humbling and challenging, because the farmers bring me back down to reality. And that's good, because then hopefully when I'm thinking systems, they're working at living it day to day, and it makes me think a lot harder, because it is complex and that's what they're working with. But, I love the field days. I got some great students that are very interactive with the farmers. And so, to see that application and the back and forth between the people living it and what we're trying to do to help them.

Dusty Weis: And it's always really great to see the thing that you've been studying play out in the field and really start having an impact, not just on people's lives and livelihoods, but on the environment as well. And so, Chuck, it has been just a fascinating conversation. It's obvious just from chatting with you here for 20 minutes, or however long we've had, that your expertise goes real deep. And so, we'll look forward to hopefully talking to you again real soon. Dr. Chuck Rice from Kansas State University, thank you so much for joining us on this episode of The Future Faster. That is going to conclude this edition of The Future Faster, the pursuit of sustainable success with Nutrien Ag Solutions. New episodes arrive every other week, so make sure you subscribe in your favorite app and join us again soon. Visit futurefaster.com to learn more. The Future Faster podcast is brought to you by Nutrien Ag Solutions with executive producer [Connor Irwin 00:30:05] and editing by [Larry Killgor III 00:30:07]. And it's produced by Podcamp Media, branded podcast production for businesses, podcampmedia.com. For nutrient ag solutions, thanks for listening, I'm Dusty Weis.