Dr. DeAnn Presley

(Jim) Good morning folks, welcome to That’s My Farm. I’m Jim Shroyer, your host. And today we’re in Riley County. We’re at Ashland Bottoms at the Agronomy Farm just south of Manhattan. And we’re gonna be talking with Dr. DeAnn Presley, our Soil Management Specialist here at K-State and she’s gonna be telling us about things that we should be thinking about-cover crops. Cover crops have really taken off this past decade and there’s lots of interest. So, come on back after these words from our sponsors and we’ll talk to DeAnn about cover crops.

Closed Captioning Brought to you by the Kansas Soybean Commission. The Soybean Checkoff, Progress Powered by Kansas Farmers.

(Jim) Good morning folks, welcome to That’s My Farm. I’m Jim Shroyer, your host and we’re in luck today because we’re in Riley County. We’re at the Agronomy Farm at Ashland Bottoms. And with us we have Dr. DeAnn Presley, our soil management specialist and we’re gonna be talking about cover crops today. And DeAnn, so the first question is, why cover crops? What’s the deal with cover crops? (DeAnn) Sure, so I get that question alot. Is it a new thing? And the answer is no, not at all. People have been doing cover crops for probably thousands of years. But in the U.S. we’ve been doing cover crops since we’ve been farming. Thomas Jefferson, George Washington, they were fans of cover crops. So a cover crop is simply a soil… a crop that is planted to improve the soil usually. So, planted commonly to either stop erosion, or put nutrients or organic matter back into the soil. So, the easiest way to explain it, is a crop that’s planted that we’re not gonna use for anything. A cash crop is one we harvest for grain, a forage crop is eaten by an animal. But a cover crop is normally referred to as crop that’s just used to improve soil or keep soil from leaving. (Jim) OK. So, one of the things I always thought about cover crops, not so much the nutrient gain from it, but just having that ground covered so there wouldn’t be erosion. But if you have a legume in the cover crop mix, then you’ve got some added nitrogen there as well. (DeAnn) But also that organic matter, building organic matter up. On average on most of our cropland, over half the organic matter is gone from where it started. So if you compare any crop in the field… (Jim) You’re talking historically, since we started agriculture tillage that’s what… (DeAnn) Yes, so if you would compare a pasture that’s never been tilled with cropland, usually there’s only about half as much organic matter. And so some of that’s because…. (Jim) The oxidation with tillage, the oxidation of the organic matter. (DeAnn) That and erosion to the best soil down at the bottom of the hill or into our creeks and streams. And so organic matter is what gives soils its nutrient holding capacity, really enhances it and the water holding capacity and also improves the soils physical properties so it’s easier to plant into a soil with better organic matter and soils with more organic matter take water a little better. So, not just the nitrogen, but also building up organic matter, that’s one of the purposes of cover crops. (Jim) Well, now, you know with the advent of strip tillage or no till, I see cover crops being an advantage, but if you work the ground then we’re back to almost where we started from of losing organic matter and that sort of thing. I see you don’t agree… I don’t see you agree totally but I’m saying with no till I see cover crops working well. (DeAnn) Well, I just say with no till we build back soil organic matter too. So, if a farmer is doing a diverse crop rotation and no tilling, they’re putting organic matter back into the soil, just that way. And if they take cover crops and add it, that takes it even more, faster. But back to the whole thing with tillage and cover crops, so truly if a cover crop is… if a crop is grown, like a legume cover crop is grown and then turned into the soil, so here behind us you can see we’re in a no till situation, but if the soil were to be turned then, you can see some tillage in the background, that’s referred to as more of a green manure. Still, that’s good for soils if a farmer’s gonna choose to do tillage, I’d rather see them do that, than not do that. (Jim) Right, right. (DeAnn) So, building soil. Giving back. (Jim) OK. DeAnn stay with us. We’ve gotta take a break right here. You folks at home, now’s your chance to get a cup of coffee and we’ll be back after these words from our sponsors.

(Jim) Welcome back to That’s My Farm. I’m Jim Shroyer, your host and we have DeAnn Presley with us, our soil management specialist. And DeAnn we talked a little bit… the introduction of cover crops there in the first segment. Now, let’s talk about some of the types of cover crops. (DeAnn) Sure, so when people ask me about cover crops, I kind of in my mind, I have to categorize them a little bit. So, there’s cover crops you can grow that are more in the summer, right after wheat. (Jim) Summer cover crops. (DeAnn) Or you can grow ’em over the winter, so try to plant them after corn or soybeans, which is tricky but can be done. So, there’s that- winter versus summer. And then there’s legume versus non legume. (Jim) Within each of those groups I suppose. (DeAnn) Yea. So there’s legumes we can grow in the summer such as sunn hemp or cowpeas, those work great. And then there’s legumes we can grow in the fall, like a vetch or a winter pea or something like that. So, whenever somebody says, “Hey, let’s talk about what I can plant.” I say, “Nope, let’s first start talking about two things, when do you want to plant ’em, between what crop and what other crop? And also, what are you gonna do with it? What’s your goal? Is something going to eat this?” So I said, in the first little part there I said, “A cover crop is something that’s not eaten.” But the fact of the matter is in practicality, most Kansas farmers are pretty practical and they’re thinking, well, what could I grow that a cow could eat? Usually cattle. So what could I grow that a cow could eat? So, I don’t actually draw that distinction say, I’m not gonna talk about forages. We have meetings all the time, we do research in which we evaluate how much biomass is produced and the quality of that biomass. So, even though I say strictly as a cover, really I don’t mean it. I’m not serious. We will evaluate forage too. So think about it all. (Jim) Yea, you’re right. Farmers when they see you know a foot and a half of forage out there of some type, whether it’s a legume or a non legume, they’re thinking OK, my cows or goats or sheep or whatever, could eat that. (DeAnn) Right and so that effects really their selection that they make from the beginning. So if something’s gonna eat it, they’re probably going to look at that and say, “What things could I select that are high biomass producing in a short window of time?” But then of course there’s the quality issues, like well, do those accumulate nitrogen? And thinking about it that way. So, there’s just a ton of extension work and research work that we’re doing right now to really gauge that, so that we can do some of the experimentation before farmers have to on their own farms. Although the on-farm experimentation that’s happening is critical too. So, we didn’t really mention brassicas earlier, but plants in the brassicasia family, those are of course non legumes, but that’s one of the types of plants that we have alot growing. (Jim) We’re talking about the brassicas, we’re talking about canola or rape seed or radishes and turnips, basically. (DeAnn) Yea, those are some of that and then there’s actually these hybrid crosses that have been made, so forage, forage radishes for example. (Jim) Right. (DeAnn) So, some of those, what’s nice about them is that if an animal were to swipe off that top, many of them the growing…it will still grow, regrow from that growing point. Some plants won’t. But the forage ones that have been bred for that, will regrow and so then they produce more biomass. Kinda like salad greens, they regrow. So again, whether somebody picks a tillage radish or they pick a forage radish, it depends on what their intended use is. (Jim) Right, exactly. Stay with us. We’ll take a break. Folks, stay with us. We’ll be right back after these words.

(Jim) Welcome back to That’s My Farm. I’m Jim Shroyer and with us we have DeAnn Presley, our soil management specialist and we’re on the agronomy farm at Ashland Bottoms south of Manhattan. And DeAnn you alluded to research a while ago about cover crops and kind of tell us where we’re standing right now. (DeAnn) First this experiment, this is a project initiated by Craig Rosenboom back in 2007. It’s been going on ever since and so what we have here, if it’s in this line kind of north to south, but there’s a wheat, sorghum and soybean rotation. But after the wheat is when the cover crop is in the experiment. It’s not after the sorghum or the soybean, just after the wheat. And so half of those crops, so half of the different treatments are summer crops. So, for example this dead residue right here is sorghum sudan grass, and this one that I’m standing in right now, if you can see kind of this darker grey, this was a beautiful standing of crimson clover, just gorgeous, red flowers, pinkish, red flowers that were growing here. (Jim) After the wheat stubble. See a little volunteer wheat here. (DeAnn) Yep. That’s gonna be dead here soon and then we’ll be planting sorghum here in probably, what a month or so, right? But anyway, so different purpose, they have a legume here. This one was a forage type experiment. And so then there’s measurements of all kinds being taken out here. So Craig has different nitrogen rates to examine the benefits, so the benefits here of a legume. (Jim) Right. (DeAnn) I think the nitrogen contribution of this crimson clover will probably be somewhere between 30, 40, 50 pounds… (Jim) Right. (DeAnn)…the subsequent crop, so it’s an excellent crop for that. (Jim) Obviously the longer it goes before it’s terminated, the more nitrogen it’s gonna fix. (DeAnn) And this year we planted it and did everything right. We were living right. We got plenty of growth off it this time, so this you might think, oh this doesn’t look like much, but crimson clover it is. Crimson clover is about the roots. So, beautiful. As a soil scientist, beautiful root system. But the sorghum sudan grass, the purpose of that was to grow above ground biomass for an animal to consume. And so that’s what the kind of research is, is not only the performance of the cover crops, but the performance of the subsequent cash crops. We have to figure out a way to monitor and pay for these cover crops. Finally if you see that trailer in the background, that’s a reasearcher named Peter Tomlinson who’s doing work with greenhouse gases. So, how does having a cover living and growing change what greenhouses gases are given off from the soil, versus a soil that has no cover crop. So, if they’re consuming… (Jim) More exposed are you saying? (DeAnn) Yea, the different exposure of soils. So, we have a bare soil over there, what’s happening? First of all what’s happening to the carbon? But what’s happening to any of the nitrogen left over in that system from the previous crop? Well denitrification, leaching if the soil type is right versus here where something is green and growing, it’ll utilize it. Sorghum sudan grass would do an excellent job utilizing that. And then perhaps releasing it back through the soil, to the next subsequent crop and maybe ending up with less greenhouse gas emission. So, and that’s his work that he’s doing there. (Jim) So, you’ve gotta couple three studies here. (DeAnn) And don’t forget about the soil quality, that’s where I come in. We measure how well the soils, if they’re changing. (Jim) OK. Hang on. I want to continue the research aspect here in a second, but we have to take a break. Folks, stay with us, we’ll be right back after these words from our sponsors.

(Jim) Welcome back folks to That’s My Farm. I’m Jim Shroyer. DeAnn Presley is still with us. She didn’t run off during the break. So, DeAnn we talked a little bit about the research a while ago and let’s continue research from other parts of the state. (DeAnn) Sure, so, we have a huge rainfall change across our state, right? So, let’s start dry first. So, John Holman is a researcher who has been doing cover crop work since 2006 at Garden City. He’s got an experiment involving two different experiments actually, one that involves putting a cover crop in a wheat rotation. So, wheat, cover crop, wheat. Or wheat, fallow wheat, or continuous wheat. That’s the kind of thing he does. And looking at effects of the cover crop on the subsequent wheat crop, but also on the value of that cover crop as a forage. And so, just to summarize his work, depends if it’s a good rainfall year or a bad rainfall. If it’s a bad rainfall year, those cover crops, they use up moisture. (Jim) And they don’t produce much either. (DeAnn) True. They don’t produce a ton… literally a ton, but it depends on the crop, cause he’s got 15 different covers that he’s evaluating, so some are you know, low biomass producers like lentils, they don’t produce much. And he’s got others like triticale that produce alot, so in those years it really depends what you grow. And then in the high rainfall years, they really don’t affect the subsequent yields very much. And when you grow a whole bunch of triticale, and feed that to something, that’s actually quite positive for income. So, you have to look at that work and think about what’s your objective? What do you want to do to make a conclusion? And then if we move… what’s Garden City, about 16, 18, 20 inches of rain? (Jim) Yea, 18- 16 to 18. (DeAnn) Depending, highly variable. And then if you move… Craig Rosenboom I said he also has another experiment in central Kansas, so Belleville and I’m not sure of the rainfall of that- 22ish, 24ish, maybe something like that. So he’s got an experiment, also after wheat, with cover crops and there’s a grad student, her name is Mattie Kirkendoll and she’s measuring the water use by those cover crops. So, very detailed work. It’s fascinating. They’re finding after wheat, plant a cover crop, you’ll get water extraction down eight or nine feet from a radish by the time that radish dies. We’ve got some radishes behind us. But by the time those radishes, because they’re not winter hardy at all, by the time they die, they use water down eight or nine feet. Fascinating. And that difference in that water, they’ve been seeing that through the subsequent crop, which I think they’ve been growing corn. And so again, is that positive? Is that negative? Well again, if it’s just truly a cover, you might… you’d have to look at those results with your intended purpose in mind. Now, let’s shift entirely somewhere different, Parsons, Kansas. (Jim) Southeast. (DeAnn) Yea, Columbus, Kansas, is where we’ve got Gretchen Sassenrath and Jamie Lynn Farney are the researchers there. And they’re measuring what happens if we plant a cover crop, actually using it for forage cause Jamie Lynn’s an animal scientist. But there they’re doing mixtures work. So, this idea, what if you mix three things together, maybe you get some synergy. So they always have a grass, so cereal, so barley and oats and maybe wheat is one of the others. They always have a brassicaceae, so that ones a radish or a turnip. And then they have a legume. So, that one… berseem clover, that has not grown at all, but then there’s some other one, I think peas. And then my grad student helps in clips. So, she’ll clip out a known area, quantifying the biomass at 30, 60 and 90 days. So, 30 days we were sticking that in gallon Ziplocs. By 60 days we had trash bags, big trash bags. (Jim) OK. (DeAnn) Sixty days was a good amount of time for some forage growth there. (Jim) OK, we’ve gotta take another break, so hang on. Don’t run away. Folks, don’t run away either. We’ll be right back after these words.

(Jim) Welcome back to That’s My Farm, I’m Jim Shroyer and in this last segment with DeAnn, we’re gonna talk a little bit about mixed crops and some other things. But let’s talk a little bit about let’s…go ahead and continue the thought process of one, two or three or half a dozen or a dozen cover crop mixtures. (DeAnn) Sure. Farmers are very interested in mixtures and there’s some good reasons for that. We have mixtures in a few of our experiments. John has one. Craign has one. So, we have mixtures. People are combining all sorts of things. And the reason they’re doing that is to gain some multiple benefits. So, if you think about a crop that’s got some short fibrous roots and think about big, old tap roots on something like a radish, which like I said they’re extracting water down to eight or nine feet. So, they’re getting good stuff down from eight or nine feet and bringing it up, such as maybe some nitrate that’s moved down, or maybe other nutrients that have become a little more depleted on the surface. (Jim) So, you’re recycling basically. (DeAnn) Recyling of nutrients. But what else? Big roots, little fine roots, they enhance soil alot. And so this equipment behind me, this is some of the stuff I do to quantify soil health. So, when we talk about soil health we’re talking about the physical and the chemical and biological properties. Now, I like to measure the physical, so we pound these rims into the ground about three inches, fill it up with water and measure how fast the water moves into the soil. And we’ve been out for the past couple of weeks. So we measure it dry and then we measure it wet again. And so, those are just some of the things that… maybe it’s hard to moditize, quantify the benefit to an individual farmer from getting water in the soil faster. But boy if they can get in there and plant a day or two earlier, than if they hadn’t, that’s getting planting done in a timely fashion. Or if water goes in rather than running off from an environmental standpoint that’s a good thing. Prevents some regulatory agencies from you know, stopping what we want to do I guess. (Jim) I’m going to go back to the mixtures again. (DeAnn) Yes. I don’t want you to think that you have… (DeAnn) What do I think the optimum mixtures, species in a mixture is? I think a person has to be thoughtful about what it is that they put in there. So, there’s people mixing winter and summer. Well, maybe I think if the summer comes up, something grazes it off. And then the winter comes on so it’s sort of like an ecological succession. (Jim) Right, exactly. (DeAnn) It’s not the real term, but you know what I mean. (Jim) Take advantage of the season. (DeAnn) Succession, yea. So things, opportunistically doing whatever. But sometimes you can design a mix really poorly and put in two things or… (Jim) That compete against each other. (DeAnn) That compete. But if you can come up with different nitches. So, I was talking about the roots and the different nitches sort of below ground, but different nitches above ground. So if you have, let’s say you have sunflowers and you put in cow peas and you put in buckwheat, well they’ve all got sort of different sort of life cycles and they use different… their leaves are different, their roots are different. Lots of great mixtures to put together. And somebody might say, “What about grass, let’s put in a grass.” But be thoughtful. What is it you’re trying to do with that? If it’s just soil health, I don’t know if you’d want to spend as much money on seed as if something was…if you’re gonna gain pounds and pounds of beef, then you can afford to spend a little more on seed, so again… (Jim) Exactly, that’s a good thought. (DeAnn) This all comes into it. So, there’s just so many questions to be answered yet. (Jim) Where can people get information about cover crops? (DeAnn) Sure, I want to show a pub that this is from K-State, and in here, there’s a chapter in here on cover crops and it’s got a table that talks about all the different uses of cover crops and then several different cover crops. This is available from any extension office in the state. (Jim) What about this one? (DeAnn) This one is called,”Managing Cover Crops Profitably, Third Edition.” And if you want to know anything about an individual cover crop it’s probably in here. So, there’s something on annual rye grass. Trying to figure out what’s the difference between annual rye grass and cereal rye, that’s in there and it will tell you… (Jim) Big difference. (DeAnn) …when to seed it. Exactly. When to seed it, how to seed it, seeding rates. When to use one and not the other. So, that’s a great reference and that’s actually online for free from an organization called SARE, Sustainable Ag Research and Education. (Jim) OK. (DeAnn) But Googling ‘managing cover crops profitably’ is a quick and dirty way to find it and like I said it’s for free as a PDF online. (Jim) OK. DeAnn I really appreciate you taking time to talk to us about cover crops. I think it’d be kind of fun to come back when they’re… some of ’em are growing and take a look at it then and some of the actual data that we’ve come up with. (DeAnn) Well, I have to say that I’m glad we did this here in 2015 because you know, 2015 is the International Year of Soils. International. UN proclaimed it so, the United Nations. So as a soil scientist we are pretty excited about that. It brings some recognition to soils. (Jim) There you go. And it’s importance around the world. Thank you. Folks, thank you for being with us on this issue of That’s My Farm and don’t forget next week at this same time we’ll have another session of That’s My Farm, so see you then.

Closed Captioning Brought to you by the Kansas Soybean Commission. The Soybean Checkoff, Progress Powered by Kansas Farmers.

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