A Tour of the K-State Soil Testing Lab

(Jim Shroyer) Good morning, folks, welcome to That’s My Farm. I’m Jim Shroyer, your host. We’re in luck because we’re on campus, Kansas State University. We’re in Throckmorton Hall. But more importantly, we’re at the Kansas State University Soil Testing Lab in the Department of Agronomy, talking with Dr. Dorivar Ruiz-Diaz, our Extension Soil Fertility Specialist and Director of the Soil Testing Lab. I think you’re going to be interested in how the Soil Testing Lab works. We’ll be right back after these words from our sponsors.

Closed Captioning Brought to you by Ag Promo Source. Together we grow. Learn more at agpromosource.com.

(Jim) Welcome back to That’s My Farm, I’m Jim Shroyer. With us, we have Dorivar Ruiz-Diaz our Soil Fertility Extension Specialist and Director of the Soil Testing Lab. If you haven’t figured out by now, we’re in the Soil Testing Lab. Dorivar, kindly explain to us the mission of the Soil Testing Lab. (Dr. Dorivar Ruiz-Diaz) Yes, Jim. The Soil Testing Lab has a couple of main missions. One of them, of course, is to provide analytical service to farmers, Extension, and homeowners. Basically the test results for soils, tissue, and water samples. But the other aspect of the lab is also providing recommendations for producers in terms of what to do with those numbers; what kind of fertility program they should be doing based on those results. I think, perhaps that’s one of the most important aspects also that we do here in the lab and we provide that information. (Jim) The Soil Testing Lab is just doing an actual analysis, half of the issue it’s the recommendations on what the producers or homeowners do. (Dorivar) Absolutely and like I said that’s a very important part of the mission that we have. Because providing accurate information in terms of specific information for soils in an environment that we have here in Kansas is a key component. For that, we required to have extensive research to do correlation, calibration; make sure that soil tests that we are using in Kansas are the appropriate ones for the soils that we have here in the State. (Jim) I want you to define that correlation, calibration aspect you just mentioned there. If someone from Texas sent you a soil sample, what do you do? (Dorivar) Yes, again, all recommendation is specific for Kansas. The way we develop that is, like I say, with research and research has been going on for many years at Kansas State University. That correlation-calibration basically means that we are evaluating the soil test in terms of what kind of response we are seeing in the crops, both nutrient uptake and yield response. When we have a number, say, a soil test of phosphorous of 20, we know what that means for all crops for all conditions here. For that, we basically need to develop field research to provide that kind of information. That value can be different from state to state. Again, depending on the soil, different types of soil, different types of conditions, different types of crops. Again all of that has an effect in terms of that recommendation that we are providing. (Jim) I wonder, you just don’t put one location out there. You have to do this at many different parts of the state, different soil types. We’re talking about 0, 20, 40, 60, 80 rates, right? (Dorivar) Absolutely, absolutely. (Jim) Explain that a little bit. (Dorivar) Yes, that’s very important, Jim, because in our case in Kansas, we do have a lot of multiple environments and soils as we go from East to West. Actually, all recommendations reflect that. Recommendations can change slightly when you are in Eastern, for example, Southeast Kansas or if you are in Northwest Kansas, because of the soils, because of the conditions. What you’re saying, in terms of being able to develop, establish research in multiple locations is going to be a key to be able to capture that difference that we have in environment and soils across the State. (Jim) We got to take a break right now, so hang on I want to talk a little bit about that. Folks, we’ll be right back after these words from our sponsors.

(Jim) Welcome back to That’s My Farm. With us, we have Dorivar Ruiz-Diaz our Soil Extension Specialist and Director of the Soil Testing Lab. We were talking just before the break about the calibration studies you do around the state. Many of them over many, many years, tell me how you do the increment, how do you know where you get that response. (Dorivar) Yes, a typical study will obviously evaluate, like I mentioned multiple rates of nutrients. We’re talking about phosphorous, potassium, and so on. Basically again we want to be able to correlate the value of the soil test that we have with the response that we have seeing to fertilizer applications. For that, we not only need multiple locations, but we also need multiple rates of fertilizer to make that evaluation basically in terms of the response. (Jim) Where do you get the- I’m thinking about optimal curve, that point of no return or – (Dorivar) Absolutely, and that optimally is one of the key things that we want to develop, but again it’s important to keep in mind that there’s a lot of work behind developing that kind of information like you say. Multiple locations across the state, a state like Kansas that has multiple environments and soils is very important. Again many years, it’s not just me, many years, and many people here at Kansas State University contribute to develop that kind of information. (Jim) Well, the K-State lab is not a big lab by any stretch of imagination, and there’s a lot of labs around the region that are much bigger, but talk a little bit about the volume and how it works. (Dorivar) Yes, again our lab is probably a small lab compared to like you say to other labs. In terms of volume of samples, we’re probably analyzing about 30 to 40,000 soil samples per year, about 15 to 20,000 tissues samples, and 5 to 10,000 water samples. Those are maybe the main things that we focus on. Of course, we do get other type of samples, but soils, tissue, and water samples are the main things that we look at. Our main clientele would be our Extension System in the state, so Extension Agents they would be sending samples to us from producers as well again as homeowners. But we also work obviously directly with producer samples, they will send their samples to us, and we will provide recommendations directly to them, again based on our research. The other aspect again like I mentioned is water, and again that’s a- (Jim) Goes hand in hand with the fertility issues. (Dorivar) Yes, it does, and especially when we’re talking about the environmental side of things because there’s an economic aspect to being able to put the right amount of fertilizer which is very important, but also we don’t want to have too much nutrients out there in terms of potential risk of water quality concerns, run off, and so on. Again, we do have some significant amount of samples for water, as well as the environmental side of things for soil testing. (Jim) You mentioned you do homeowners and farmers and researchers as well, break that down. Is it half or better that are farmers and County Agents and Extension Systems? What is it? I don’t know. (Dorivar) Yes, more than half probably of all what we do is coming from Extension and farmers, and then a smaller amount of what we’re doing is research, and again these are providing service to researchers, not just here at Kansas State. But actually all the universities in Kansas, and even out of state researchers that send their samples to us. (Jim) We got to take a break. Folks, we’ll be right back after these words from our sponsors.

(Jim) Welcome back to That’s My Farm, I’m Jim Shroyer, and Dorivar Ruiz-Diaz didn’t run off during that break, and I’m glad that you didn’t too. Dorivar, let’s say I’m a producer out there, and I know what the wheat prices are, and I know what the corn prices are, they are not really good at this particular point, so I’m in the mindset that, “I don’t want to spend a whole lot of money on this crop that’s coming up, or next year.” Is that a good thought process that I have or should I be thinking in otherwise? (Dorivar) That’s a very good point Jim, and actually we have that comment pretty often obviously. Producers are looking at ways to cut costs as much as possible. But research actually from colleagues at the Department of Ag Econ here at Kansas State University shows that soil testing perhaps is the one thing that is even more important to be soil-testing under these conditions of low grain prices and tough economic situations. (Jim) That’s almost counter-intuitive, but it’s not really. (Dorivar) It is, but if you think about it Jim, basically when you have again tight budgets, you want to be able to make the right decision. To make the right decision you need to have good information, and soil testing that’s basically what it is giving you; it’s giving you the accurate information in terms of what you have there already in terms of nutrients, and obviously you don’t want to put more fertilizer than you have to. On the other hand, if you are sure of some nutrients, you want to make sure you are putting that nutrient, so you’re not losing yields, because at the same– (Jim) That may be the limiting factor. (Dorivar) That may be the limiting factor. At the same time obviously, you don’t want to be leaving bushels out there that you can capture with proper nutrient management. Again, that’s the key there, like I said, there’s been some study evaluating that. Again, the value of soil testing, if anything, has a lot more value in times where we, the importance of the information is critical like now. (Jim) Also, you think about, obviously we did have a drought this year, we did for a while, but then that cleared up. In drought years, you can have a lot of carry over in nutrients. If you’re just used to putting on X amount of nitrogen, or phosphorus, or potassium, you could be running into some problems. (Dorivar) Absolutely, and that’s actually, one part of the mission that we have here in the Soil Testing Lab, is to look at that kind of things. A few years ago, during severe drought, we looked at little bit of a survey of how much residual nitrogen we have in some fields in the state. It’s very impressive Jim. You can find things anywhere from 100 pounds to 150, 200 pounds of nitrogen in the field. Obviously in that kind of situation, you- (Jim) Your wheat wouldn’t need anything. Your milo probably wouldn’t need anything. Maybe corn just a little, maybe. (Dorivar) Maybe a little. Again, you want to know that. You want to know that and be able to save money on that fertilizer. Obviously, soil test can give you that information. You mentioned, this year we have good yields. It’s also happening, it’s also important to look at soil test. Why? Because we probably going to have very little nutrients. (Jim) Carry over. (Dorivar) Carry over. That’s also important to know. That means maybe we need to make a little bit more adjustment next year as well. It’s basically not just when you have drought conditions, but also when you have good yields. Remember, we are removing more nutrients as well when you have good yields. Again, soil test is going to be able to, it is going to give you that information to make those adjustments. (Jim) Dorivar, we got to take a break. Folks, we’ll be right back after these words from our sponsors.

(Jim) Welcome back to That’s My Farm. I’m Jim Shroyer. With us, we have Dorivar Ruiz-Diaz, the Director of the Soil Testing Lab. Dorivar, in a lab situation, you have various technicians, various machines, how do you know you’re accurate? (Dorivar) Absolutely, and that’s a very important question Jim. Actually, we get that question very often from producers. Is that lab, is the number I’m getting, is it good to make that decision? The decision we’re making is going to have significant implications; economical implication. There’s two components to that Jim. One of them is what happens in the field. How we are collecting those samples. That’s going to be a key first step. (Jim) You don’t give your hired man, or woman the bucket and say, Go take a soil sample, and just walk into the gate and dig right there. One sample for 160 acres, right? (Dorivar) [Laughs] Yes, absolutely. We always emphasize that, but it still happens sometimes. Like you mentioned, it’s very important to collect samples that are going to be representative of the field. That means we want to take multiple sub-samples in area that we are treating. We want to pay attention to a few other things as well. The number of sub-samples that we are collecting, the instruments that we are using. We want to make sure we use plastic buckets, and buckets that are clean, that are not going to contaminating all our soil samples. We want to make sure we are collecting samples at the right depth. Again, our recommendations are going to be based on certain sampling there. For Kansas, we use six inches for the immobile nutrients, 24 inches for the mobile nutrients. (Jim) Like nitrogen. (Dorivar) Like nitrogen. Again, that’s going to be also another key aspect. Then of course, once we collect the samples, we want to make sure we are not leaving it sitting in the pickup for several days and that sort of thing. We treat that sample well until it gets to the lab. Once the sample gets here in the lab, we do have a very strict protocol, steps that we follow. Actually, our lab is certified with the National Program, which is the North American Proficiency Test program. This is one example, Jim, that, they sent us some samples that we test several times a year, and they basically provide us feedback in terms of how we are doing in terms of the accuracy. Again, that variability in terms of values here in the lab, chances are very low that we’re going to have issues. Most of the time it’s usually anything that happens in the field and to the point that the sample gets here. (Jim) Okay, thanks, Dorivar. We’ve got to take a break. Folks, we’ll be right back after these words from our sponsors.

(Jim) Welcome back to That’s My Farm. I’m Jim Shroyer. With us, we have Dorivar Ruiz-Diaz, our Extension Soil Fertility Specialist, and Director of the Soil Testing Lab. Dorivar, we’ve talked a lot about the lab, the mission, and that sort of thing. How does the sample get here? (Dorivar) Yes, that’s a very good question, Jim. There are many options for a producer or homeowner to send their samples. One of them that is very common is through the County Agent at the- (Jim) Extension office? (Dorivar) The Extension office. Basically, the producer can work with the County Agent and Extension office at the county level, and they can send the samples to us. Another approach is also for the producer to send the samples directly to us. Actually, in our website, we give information for shipping instructions, as well as provide shipping labels actually that you can print at home, put it to the box, and that will get to us pretty much overnight. (Jim) From the time you receive a sample, how long does it take before the producer or the homeowner gets the results? (Dorivar) Yes, once a sample gets here, we usually have a turnaround time of about two days. Within two days, you should get back your results. Right now, there’s a few ways the results are getting to the customer. One of them is again through the website. Actually, the customer can setup an account, and we are giving all the results, all the status of the process in that website. Also, we are sending an electronic report via email. As soon as the results are ready, we provide the recommendations. We review the recommendations, make sure they are accurate, and then immediately we send that via email. That way that’s available to the producer immediately basically. Again, we can also provide the reports via regular mail. But more and more, we don’t have many people requesting that. (Jim) You keep the sample on hand for two to three months? (Dorivar) That’s right. That’s one of the main reasons why we do that, is because again we want to give some time to the customer to look at those results, make sure they don’t have any additional questions. Because if they do have more questions like you say we keep actually the sample here for about three months. If they have any questions about, they may want to look at other nutrients. For example, we can go back and re-test, and provide additional information on that same sample. That way the producer doesn’t have to go back and collect samples from the field. (Jim) One question I used to get all the time, and I’m sure you do too is, how often should I soil test? (Dorivar) Yes, that’s another very important question. Typically, we will recommend for pH, organic matter, P and K. At least– (Jim) The basics, that’s the basic- (Dorivar) That’s the basic analysis. That would be at least every three to four years. Again, depending on how things are, and how much information we have, we may even need to do that more often. Again, if you are a farmer that you are just trying to work on that specific field, you may not have much information on that. In that kind of situation, you may want to be looking at soil testing maybe every two years, until you have a better feeling about what kind of values we have there. (Jim) A baseline? (Dorivar) A baseline, yes. (Jim) Dorivar, I appreciate you taking time to tell us a little bit about the K-State soil testing lab. I appreciate it. I’m sure producers enjoyed that. Folks, thank you for being with us and don’t forget next week about this same time, we’re going to have another show of That’s My Farm. See you then.

Closed Captioning Brought to you by Ag Promo Source. Together we grow. Learn more at agpromosource.com.

No Comments Yet.

Leave a reply

You must be logged in to post a comment.