Ag Geek Speak
GK Technology Inc Team Members, Jodi Boe and Sarah Lovas talk about precision agriculture, agriculture mapping, agronomy and drainage.
Ag Geek Speak
15. Digging Deep into Soil Science with Professor Emeritus R. Jay Goos
Discover the secrets of soil fertility, straight from the expert himself, Dr. R. Jay Goos, Professor Emeritus at NDSU. From his humble beginnings on a farm in western Iowa to becoming a revered educator, Dr. Goos shares his unique journey. Immerse yourself in his passion for soil fertility and some helpful takeaways from Introduction to Soils. Sit back and listen as we discuss practical applications of soil science, the perfect intersection of earth science, biology, chemistry, and physics.
In this episode, Dr. Goos walks us through his extensive research work on chloride fertilization, urease and nitrification inhibitors, and phosphorus fertilizaiton in wheat. We dive into the challenges and triumphs of his research on Iron Deficiency Chlorosis (IDC) in soybeans, and the vital role of chloride as a micronutrient in North Dakota agriculture. Gain an understanding of the historical and contemporary practices of chloride application, and the significance of iron in plant health, all through the lens of a seasoned soil chemist.
In the final segment, join us for a deep dive into the advancements in soil microbiology and precision agriculture. Dr. Goos contrasts traditional soil microbiology methods with modern DNA testing, addressing the challenges of interpreting extensive data. Explore the dynamic rhizosphere affected by IDC and the innovative solutions provided by variable rate technology (VRT) in managing it. We wrap up with a discussion on the forward-thinking solutions from GK Technology, and our shared enthusiasm for putting these concepts to the test out in the field. Don't miss this stimulating conversation packed with insights about soil chemistry with the soil chemistry legend that is Dr. R. Jay Goos.
And now it's time for Ag Geek Speak, and this week we have a very special guest with us today Professor Emeritus from NDSU, Dr. Jay Goos. He actually was also my major professor when I got my Master's degree in Soils, so he put up with me the whole time and I really appreciated it. It was a great experience and so super excited to have you on yeah, so thanks for being here. Thank you, Dr. Goos. Let's talk a little bit. You retired from NDSU not so long ago, but let's talk about where you began and how you got interested in soils and led you to getting into soil.
Dr. R. Jay Goos:Well, I was a farm boy in western Iowa and in high school I loved all of my science classes earth science, biology, chemistry and physics. I liked all of them and I was also a farm boy and when I went to college, you know I thought about this. I guess I liked I came to soil science because it was one discipline that used all of those earth science, biology, chemistry and physics and so it was an intersection of all of those. And, like many who find a career in soil science, I had a very good intro soil science class in college, so I think that was one thing that directed me that direction.
Jodi:And luckily for many students at NDSU too, they also had a very good introduction to soils professor and you as the teacher of SOILS 210 for many many years.
Dr. R. Jay Goos:I enjoyed teaching that class a great deal years.
Sarah:I enjoyed teaching that class a great deal. So Dr. Goos had all of these great strengths at NDSU that I remember teaching one of his greatest attributes. I was fortunate enough that when I was an undergrad I actually got to take soil fertility from him, and then, when I came back to NDSU, also got to take intro to soils 210. And it didn't matter which subject I took, you were very good at bringing it to life, making it real, getting us into the depths of the theory of why things work, but also making it extremely practical, and so it was just one of my fondest memories. I would have never have gone into soils for a master's degree if it wouldn't have been for that soil fertility class all of those years ago. This might be a little bit out of order, but what was one of your favorite things that you remember? Teaching your students?
Dr. R. Jay Goos:Well, you know, when I was teaching soil fertility and fertilizers, I realized that you know not many soil fertility textbooks also teach fertilizer technology and so I taught not only you know the fertility in the soil, but I also had labs on fertilizer technology and I liked teaching that quite a bit. As far as intro soils, I really did like teaching the pedology part of it, the first third of the class. You know, just like the antenna is a part of an insect, you know what are the parts of the soil, the various soil horizons. You know I really enjoyed that part of the teaching it as well.
Sarah:One of the things when you were teaching the pedology portion. I can remember that you spent all of this time driving throughout North Dakota to go and get pedons from different areas of North Dakota, really to help show the differences of North Dakota soils. I'm trying to remember what were all the locations. There was Streeter.
Dr. R. Jay Goos:Yeah, so, yes, so the way the labs were set up. There were eight stations in each lab and there were eight different soils from North Dakota represented in the lab. There was a sandy sandstone soil from Dickinson. There was a clay pan soil from Hettinger. There was there from Streeter, it was outwash from Langdon, it was salty. From the Red River Valley it was high water table and then there was a normal soil from Carrington. Congratulations, Carrington, on your normal soil Normal soil from Carrington so so interesting to think about.
Sarah:Okay, what we do in precision agriculture all of the time and how these different soils all over can really affect how we see differences across the landscape, and and actually see that in your class and and have it brought to life was just that was pretty fun. It's been over 10 years since I took it's been 10 plus years since I took Dr Goos's class. See that in your class and have it brought to life was just that was pretty fun.
Jodi:It's been over 10 years since I took it's been 10 plus years since I took Dr Goose's class, but I remember that we had a Prosper soil that my lab partner and I worked on to do our final presentation on.
Dr. R. Jay Goos:Well, you know, pedology was always really important to me. When I was an undergraduate, in the summer of 1975, I went to South Dakota State University and I spent the summer in Mitchell, South Dakota, and I had the entire summer being trained in soil mapping by Warren F Johnson, who was the legend of soil survey in South Dakota. So I had about as good a training in field pedology as a person could get. And you asked me what my favorite soil series is.
Sarah:Yes.
Dr. R. Jay Goos:Well, I don't have a favorite soil series, but I do have a favorite soil horizon. And since this is Ag Geek Speak, and since this has to do a lot with precision ag, I do want to talk about my favorite soil horizon. My favorite soil horizon is whatever comes immediately after the A horizon, because if you're on fairly level ground in North Dakota, A horizons all look about the same, but it's what comes next that tells the whole story. I mean, for example, if you're on level ground and the A horizon is followed by the parent material, you're on a floodplain, you're on the floodplain of a creek or a river.
Dr. R. Jay Goos:If the A horizon is followed by a soil that fizzes a Bk horizon well, you're on a soil with a high water table, you might have IDC and you're going to need some pumps for your basement. If the A horizon is followed by what they call an E horizon, well, in eastern North Dakota, that means you're in a pothole and the government ain't going to let you drain it. If you're in southwestern North Dakota and you have an A horizon followed by probably a narrow E horizon, you're on a wicked clay pan and that's a nasty soil, and so on. If the A horizon is followed by a clay pan, you've got a clay pan and then, like we were talking about at Carrington, if the A horizon is followed by what we call a Cambic or a Bw horizon, everything is nice. So I have a favorite soil horizon and that's basically what comes after the A horizon.
Jodi:I love that. I love that so much. And, backing up a little bit, can you explain to us again, like what are the main soil horizons and what in general they mean?
Dr. R. Jay Goos:Yeah, well, in soil science as a whole there are five master horizons. The O horizon you're either in a peat bog or you're the layer on a forest soil. You got the A horizon. We know what an A horizon is the top soil. There can be an Eizon. In forest soils those are very common. That's a leached out horizon. But in prairies that generally means you're in somewhere that collects water and the b-horizon can be almost anything, and then you've got the pair of material. So those are your basic horizons, but the complexity of the soil is in the b-horizon normally.
Jodi:Did you teach us in class the way to remember the horizons? Is it only apes eat?
Dr. R. Jay Goos:bananas yes, only apes eat bananas constantly. Yes. O-a-e-b-c.
Jodi:O-A-E-B-C.
Dr. R. Jay Goos:I would have that as my license plate, but nobody would know what it meant.
Sarah:I don't remember that, but I do remember that E is the middle of the Oreo cookie.
Dr. R. Jay Goos:The E is the middle of the Oreo cookie. In a prairie soil, if you have an Oreo cookie with a black A horizon and a dark B horizon, and the E is the middle of the Oreo cookie, and you're in a pothole and the government ain't going to let you drain it.
Jodi:Are there soil series that are defined as that series because they have that E horizon?
Dr. R. Jay Goos:Oh, yeah, the Tonka soil in North Dakota and the Teetonka soil in South Dakota are the two most common in this area.
Jodi:That's really helpful to know and remember. I think thinking about like if you're coming across or looking across at a soil series map, if you see that that's most likely someplace that's constantly wet, tonka and detonka.
Dr. R. Jay Goos:Yeah, podology, you could I guess this is ag geek speak, so that we can geek out on soil horizons.
Sarah:We can geek out on anything we want.
Dr. R. Jay Goos:That's the whole point. Well, anyway but yeah, podology is important and you know I'm not being critical in the sense that I'm glad that the tech schools and the colleges are having majors in precision ag. But what varies across the field? Does the sunshine vary across the field? The rain may be a little bit, but not predictably. But it's the soil that varies across the field. There really needs to be curriculum development with regards to soil variability and with regards to precision ag. I think that needs to be developed.
Sarah:It's interesting that you bring that up, Dr Goose, because I feel like that's actually something that Jody and I talk about all of the time. Jody and I talk about all of the time. How do you look across a field and how do you think about how that field is acting? And is it topography? Well, topography is part of it, but it's not all of it. Is it soil texture? Well, yes, but it's the whole of everything.
Dr. R. Jay Goos:You know, in confirmation we learned the 10 commandments, but in soil science we got the five soil forming factors and if you dig a hole here and you go 10 steps and you dig a hole there and it's a different soil, we have a very coherent way of thinking about it. What varied? Are you on a different landscape position? Are you on a different parent material? Usually you're not under a different native vegetation, although in parts of Minnesota in the same field you can go from prairie to forest and it's all been cleared, and so that's not guaranteed either here in northern Minnesota, you know. So I mean, the five soil forming factors are our mental checklist as you go across the field and see different kinds of soils.
Sarah:Are you referring to clorped Clorp?
Dr. R. Jay Goos:yeah, okay, climate, climate relief. Yes.
Sarah:Climate living organisms Yep yep yep Relief typography.
Jodi:Time, not topography. Relief is the topography, and then T is time. Yep, yep, that's right. There it is yeah.
Dr. R. Jay Goos:I'm glad I gave you good grades in soils.
Jodi:Secret. We talked to Tom DeSutter last week about clorps, so we did have a little bit of a cheating refreshment here.
Dr. R. Jay Goos:Okay, so you mentioned that you worked with Warren Johnson. The legend of—.
Jodi:Soil mapping in South Dakota. Soil mapping in South.
Dr. R. Jay Goos:Dakota yeah.
Jodi:When you did your graduate work at South Dakota State. Was that related to your graduate work?
Dr. R. Jay Goos:No, you know, and I was offered an assistantship in podology, but no, I worked with soil fertility and I worked with soybean fertility as my master's and then my PhD. I went to Colorado State and I worked with wheat fertility, and so it was just. I don't know why I chose one or another, just the opportunities were there.
Dr. R. Jay Goos:And then, when I graduated from graduate school at Colorado State, how did I end up at NDSU? Well, I basically had three offers. This was a traditional land-grant college and it was within three or four hours of my wife's family, so it was a logical choice and NDSU was certainly very good to me for 40, 42 years. So, yeah, it was a good career and a good place to work. We have very good experiment farms and I think that was another big strength of the NDSU system.
Sarah:You've done a lot of different soils research throughout the entire state of North Dakota in your time. What were some of your most memorable research projects that you've done over your career?
Dr. R. Jay Goos:Well, it kind of evolved. You have to remember, in 1980, when I walked on the NDSU campus, a peanut farmer was the president of the United States and the number two crop of North Dakota. It wasn't barley and it wasn't sunflowers, it was cultivated summer fallow. We had three million acres of cultivated summer fallow. Almost the western half of the state was almost entirely wheat and summer fallow, with horrible effects on the soil health and saline seeps, and so my first charge was just to develop nitrogen recommendations for the western part of the state, and things evolved from there.
Dr. R. Jay Goos:I worked with chloride fertilization and plant diseases. I worked with urease and nitrification inhibitors, and then I worked with phosphorus on wheat nitrification inhibitors and then I worked with phosphorus on wheat and then later in my last half of my career, I worked with iron deficiency chlorosis Ted Helms I thank Ted a lot. Our wheat, our soybean breeder. You know the soybeans were coming in in the late 90s and the chlorosis was a problem, and so I started working on that. Fortunately, my professor of soil chemistry at Colorado State was Willard Lindsey, who came up with the DTPA soil test that everyone uses, and we just had phenomenal education with regards to micronutrient chemistry as well. So that fit pretty well.
Dr. R. Jay Goos:So I ended up with IDC and I should say that my research career isn't over. I do have a small lab with a couple growth chambers and I'm still evaluating iron fertilizers for companies. Companies come up with iron fertilizers. They know how to get a hold of me. I've done some variety screening for the food grade industry and so on, so I'm still involved with iron chlorosis research. I know how to screen things either fertilizers or varieties under controlled conditions and people are still asking me to do it.
Sarah:It's important to note that, especially when it comes to iron chlorosis research, inducing a controlled, consistent IDC in a greenhouse iron chlorotics plant to a point where you can actually do some good demonstration that's not easy to do.
Dr. R. Jay Goos:It took a lot of work to get the procedures down. That's true. The problem with iron is there is so much of it in the soil. You know a soil is what? 4%, 40,000 parts per million of iron. You know, the root zone of a soybean plant probably has hundreds of thousands of pounds of iron and a little plant will die because of the lack of a few grams per acre of it. There is so much iron in the soil and the plant needs so little that it's easy to get it wrong, you know, and the plant either is totally green or totally dead. But it took a while to figure that out. I'm just glad to help the fertilizer and the seed industry in that regard, because I really don't know of many people in the United States that can actually do that. A lot of people work with iron, get frustrated and move on.
Jodi:I mean we've talked about this before. I mean any sort of long-term research or like sustained in one single area, specifically in production, agriculture, I think is something you don't see very often because the funding sources, it's just the nature of research.
Dr. R. Jay Goos:It's very hard to do long-term anything Well maybe I was lucky because I had such a heavy teaching load that you know, I wasn't expected to have a laboratory with six graduate students and things like that. I wasn't expected to get a multi-million dollar NSF grant. The five-digit figure I got from every year from the Soybean Council was plenty. And you know and I thank them a lot too they still see the value in that work. I mean, there's two kinds of problems on the farm, right, there's the problem the farmer knows about and there's the problem the neighbors know about too. And when your whole field turns yellow, the neighbors know about it too.
Jodi:So yeah, and before we talk, because I think we can spend a lot of time talking about IDC and some things that we can do to address that.
Jodi:On the precision ag world or precision ag level, I'm curious. You mentioned chloride before and I think most places outside of the Northern Great Plains when they think of chloride they think of it as being a problem if there's too much of it. Right, like in the South, they breed soybeans to have chloride exclusion right to make sure that they're not getting chloride toxicity, soybeans to have chloride exclusion right to make sure that they're not getting chloride toxicity. But here in North Dakota we do test our soils for chloride because we need to know for small grains. Can we talk about your research? I mean, was that due to the research that you did?
Dr. R. Jay Goos:Chloride comes from the rainfall, from ocean aerosols and North Dakota and eastern Montana. When you think about it I can't know in round numbers we're 1,500 miles from the Pacific Ocean. We're 1,500 miles from the Gulf of Mexico. We're 1,500 miles from the Atlantic Ocean. We're 1,500 miles from Hudson Bay. You know we're a long ways from saltwater, about as far as you can get, and we have essentially no chloride in our rainfall. And so if you have a soil that's leached out, that where the salts have been leached, you know back in the 80s you could find soils with almost no detectable chloride in them, and chloride is a true micronutrient.
Dr. R. Jay Goos:And there was all this work in the 50s and 60s at NDSU. They would put 15 pounds of K2O as potash, potassium chloride with barley and they almost always got plumper kernels, 5% or 10% more yield. And there's no reason for that based on potassium, because there's no starter effect on potassium. Potassium plants have no trouble getting potassium, and so you know about that time I started on that in the early 80s they were showing chloride responses in the Pacific Northwest Tom Jackson at Washington so it was just a logical thing to try it here. But you know it's much less of a problem now because they're throwing a little bit of potash pretty much into everything now and it doesn't take much. But back then these farmers were planting wheat on summer fallow using 50 pounds of starter and a spray of 2,4-D amine and calling it good. You know that was farming right. So to come out and say, yeah, we need some chloride, it was a radical idea at the time.
Sarah:To a certain extent it is still a little bit radical today, but yet at the same time, it's one of those things on a soil test, especially for small grains I pull all the time for my growers and I'll watch that test. And there are certain situations, especially in the last couple of years, we've had some barley markets that were pretty, pretty valuable, and so making sure that we had that chloride dialed in on that valuable barley at the time was really important, and so I would make that recommendation for those growers.
Dr. R. Jay Goos:These were never full-blown deficiencies but they did have full-blown chloride deficiencies in eastern Montana. Rick Engel showed that, that you actually got the true textbook chloride deficiency symptoms in eastern Montana and so on. But again, I think it's less of a problem now because the farmers, you know the dealers, are putting in some potash in with their starter mixtures or whatever.
Jodi:Thinking about eastern Montana, right, I mean, out of all the areas of North Dakota, minnesota, south Dakota, eastern Montana probably has the highest, I think, still like residual amount of potash or potassium right, so like off the charts there's really not a whole lot of reason to be putting out that potash when you've got 600 ppm of potassium.
Dr. R. Jay Goos:Yeah, and Earl Scogley, my counterpart in eastern Montana back in the 80s, I mean he was showing he called them potash responses, but they were to potassium chloride, you know. I mean. So the history was there, it was just figuring out what it was from, you know. But in a way it's a distinction without a difference, because if you need chloride you're going to use potash, right? So potassium chloride.
Jodi:Yeah, that's really cool and it's such an important piece of North Dakota fertility.
Dr. R. Jay Goos:Do you know of anybody else that's really worked on chloride to that level where we really Well, the three people who worked on it the most were Rick Engel in Montana, me in North Dakota and Paul Fixen in South Dakota, before he went with the Phosphate and Potash Institute. Yeah, I think the three of us pretty much nailed down that we needed it Rick on wheat mostly, me mostly on barley and Paul on wheat as well.
Jodi:Can we geek out for a second on the mechanism of what is going on when we don't have that chloride there?
Dr. R. Jay Goos:Well, ok, I mean it is a true micronutrient. It is a nutrient you can actually get deficiency symptoms of it, and they had those in Montana. I wasn't so sure what was going on in North Dakota. I mean the chloride is. With regards to water relations, I mean they don't give you salty popcorn in a bar because they're worried about your corn deficiency right.
Dr. R. Jay Goos:You know they want you to retain more water and the chloride helps plants retain water. We saw earlier heading maybe a day longer of grain fill and we also saw we also could measure a reduction in a root disease quite routinely. Now those aren't the things that give you huge yield increases. You know a plumper grain, maybe a reduction of a low-level disease. You know you're talking 5%, 10% yield response. Now, rick Engel, in Montana they had full-blown chloride deficiencies. They were able to get, you know, 10, 20 bushels of wheat difference. For us maybe it was more about water relations and disease resistance and a little earlier heading a little longer, maybe a day and a half longer of grain fill.
Jodi:So, like if you're someone that's really trying to push small grain yields and you don't have that critical level of 40 pounds of chloride in your two-foot profile, chloride is definitely something that you want to add to maximize those yields.
Dr. R. Jay Goos:Yeah, and of your fertilizer elements, it's probably one of the cheapest ones to add to.
Jodi:Oh, that's a great point. It's an economic micronutrient.
Sarah:You mentioned this earlier, but when you talked about going to school where you could find that intersection of all of the sciences, and we haven't talked a lot about this, but I know that you've thought about the biology in the soil quite a bit and I can remember you developing some labs for soils 210 around mycorrhizae and things like that and so I'm going to lob up a really open and very general question for you to just have fun with. When you think about soil microbiology, just what do you think about, or what are your favorite parts of soil microbiology?
Dr. R. Jay Goos:Oh boy, yeah, I mean, I know that that whole. That's probably the one aspect of soil science that's probably going to change the most, just because the tools are so, so advanced. I had as good a training in soil microbiology as could have been had. I had it from Dr Pengra at South Dakota State, one of the most beloved professors that ever was on that campus. And you know, we plated, we did all of these chemical tests to try and identify various things.
Dr. R. Jay Goos:Well, now they send the sample away and they can test because of DNA. They can test for thousands of different types of organisms in the soil. For example, right now I'm on the graduate committee of a student in microbiology and we're studying IDC and she's studying the rhizosphere of susceptible varieties, resistant varieties, with and without soy green. She's looking at the components of. You know what organisms are the soil, are the plants favoring and promoting, and how is the IDC making the plants change the microbiology of the rhizosphere? We couldn't do any of that back in the day. Yeah, we couldn't do any of it to that degree, and right now it's such an information overload. It's such an information overload. And the eternal Lutheran question is what does this?
Jodi:mean I think it's kind of the same struggle that parts of precision agriculture also face too, right when we think about doing these big DNA screens and all of a sudden it's like, okay, we've got these thousands of microbiology or microorganisms that are living here. It then becomes a question of okay, we know it's here, but what does that mean? I mean, we're also missing the disease triangle or like these aren't necessarily causing disease, but do we know if its presence actually means that it's doing something? And same thing with, like precision ag and big data. Right, we're collecting a lot of information, but sometimes it can be hard to condense it and turn it into something that we can use and make meaningful.
Dr. R. Jay Goos:Yes, I know we're able to collect information about these organisms in the soil. And again, yeah, what does it mean and how do we harness it? How do we exploit it? Okay, so the plant undergoes IDC. The plant favors a new population of organisms. Which one of those do we isolate and use as an inoculant to help alleviate the IDC?
Sarah:Just going back to the day of thinking about iron chlorosis in the rhizosphere, I can remember reading some of Lindsay's research where he had shown that the rhizosphere I can remember reading some of Lindsay's research where he had shown that the rhizosphere of a soybean plant has the ability to lower the soil pH by one whole pH unit. That's huge. That's something that humans can't figure out how to do. But yet that's only the chemistry portion of it. We're not even scratching the surface at the biology within there, and so my questions in my mind when we start thinking about soil biology and the rhizosphere immediately go to okay, so we've got iron chlorosis going on in this area. Not only what sorts of organisms are going on, but if you've got that acidification going on in that rhizosphere, what is that doing to the soil biology and how is that complementing or making things more challenging for the soil biology? It seems like it's such a place where we are just learning so much about what's there and it's going to be just so fun to see what's going to happen.
Dr. R. Jay Goos:And there will be false starts. Right, There'll be false starts where we'll think that something's happening but we can't prove it out. And also, the soybean root not only can acidify but also can release reducing agents. There's only three ways to make soil iron more available there's acidification, there's reduction and there's chelation. Those are the three ways, and the chelation can go both ways. I mean, we talk a lot about the siderophores that plants can give off or microbes can put out. Well, sometimes, when a microbe produces an iron siderophore, it's not to make iron more available, it's to starve their neighbor of iron you know, what is a siderophore?
Dr. R. Jay Goos:It's basically a type of chelate or something that binds up iron, and it's often thought that, well, siderophores are good, they take up iron and then when those are decomposed, they can make iron available. But they're basically, they're like, I guess they're a form of chelation. It's a form of tying up iron into an organic compound.
Jodi:So is it kind of like when you're playing Mario Kart and you don't want your like competitor to beat you, you like throw a turtle shell at it and like it binds to their like tire and they can't move.
Dr. R. Jay Goos:I don't know, but I have a game to try.
Jodi:But it's like a competitive, a competitive chelation, where you're.
Dr. R. Jay Goos:It's a competitive thing, yeah, and sometimes it's to make iron more available. But sometimes the siderophores make iron less available, at least in the short term.
Jodi:Oh my gosh, that's so cool.
Dr. R. Jay Goos:Yeah, you have to think of the soil microbiome as a war.
Sarah:That's really fun.
Dr. R. Jay Goos:It is a war. I mean, those organisms are competing for everything and there's a lot of them.
Jodi:I love that and this is a good place, I think, to stop the first part of our discussion here with Dr Goose, and I think what we'll probably pick up on next week is continuing discussion of what this oil looks like at the soil level, but also more of the science of IDC too, and what are the things that we do. For sure know that we can do a better job of applying some of these precision agriculture concepts, vrt, et cetera to better manage IDC, but it has been an awesome conversation geeking out about soil science with Dr Yusuf the last half hour.
Sarah:I can't wait to geek out again?
Jodi:Yes, please join us in our next episode to do more of the same. But with that, thank you guys. So much for listening and remember, with GK Technology, we have a map and an app for that.
Dr. R. Jay Goos:And I can't wait to get in the fields again? No, I can't wait to get in the fields again.