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Utilizing Crop Rotation and Sequencing in Cropping Systems


(Music) I told him, I’m the old experienced guy said the only thing worse than being between you guys and ice cream is to be between you guys and happy hour, so. And I’ve done both of those or all those. I got some things here. We’re not going to be able to cover everything we do at Dakota Lakes in very short period of time but it’s really all about water. If you think of a farmer, what he’s trying to do is take sunlight, water, and carbon dioxide and turn them into products you can sell period. And how efficiently we use the water and for you know there’s a lot of young people here, but 30 years ago this area was winter wheat summer fallow. And we didn’t have the grain bins, and we didn’t have the didn’t have the wealth that we have right now in central South Dakota and the difference between then and now is we’re doing a better job of using water. That’s and so we’re gonna focus a lot on that today. This first handout and there’s more than what you need because some of you guys are sneaking out leaving us but that first handout really deals with plant water relations. And it’s quite complex, and we spent a lot of time listening to the meteorologists say well boy is it gonna rain? We need to have rain. But if the water doesn’t go in the ground when it does rain doesn’t do you a dang bit of good. We used to get the same amount of rain as we get now but we’re just using it better because in the old days that ran off and the old days we thought we need to have irrigation to make central, South Dakota productive. In fact they used to think they had to take water from Oahe reservoir over to Redfield to irrigate the Jim River Valley, so they could grow corn. And a lot of you young guys don’t know that but there’s a canal located not very far north of here where they were gonna actually do that and take, cover up the city of Blunt and take water over to the Jim River Valley, so they could irrigate that. And I almost didn’t get my PhD because in my thesis defense or in my final orals I made the statement that I thought we could very successfully grow corn and soybeans in Jim River Valley’s long if we when doing tillage. And we didn’t need the irrigation project and one of the guys on my committee of course had spent his career working on that irrigation project so I wasn’t very smart of me to say that. But so you have some physical characteristics of the soil and you heard Jason Miller talk about that. Jason’s done a lot of work here. Soil compaction, soil texture. Soil texture, you can’t do anything about but soil structure you can. We’re going to show you that today and one of the problems we have like in the Corn Belt, or we had here when we did summer fallow and things as we took soils that held eight or ten inches of water and then with tillage and time and compaction and the wrong rotation we turned them into soils that held six. So now what happens is when you get a big rainfall you become overly wet too soon, and you get lots of runoff and flooding and that kind of stuff because water just that soil doesn’t hold as much water as it did in the old days. And you can you can look at any gauging station you want to and that’s true. And then the on reverse side is once it turns dry, you don’t have as big a bucket when you start it, and you get drier sooner and so what we’re trying to do here is to build our capacity to hold water, get the water go in the soil, keep the water from evaporating once it’s in the soil. All these little things we’re doing and then by having the macro pores and things we’re going to show you, to allow that plant to explore that soil and get all the water out of it, but it can’t do that if it has a diseased root. Because it has bad rotation, or it can’t do that if it gets plant diseases because it has a bad rotation, and they can’t do that if you do something stupid, right. So that’s all that’s really what this talks about. Not a not a major thing. I’m getting rid of last year’s, last year’s rotational thing. This has all the records up through 2011 at the Dakota Lakes Research Farm on a dry land, on our dryland fields. We’ve done the same or similar rotations on the dry land portion of this farm and we’ve had lots of rotations studies other places and whatever, but the dry land portion of this particular site, we’ve had very similar rotations that have gone on for 20-some years. And you can look at what’s happened to those up through 2011. The reason I’m getting rid of those because we had them left over. See in 2012 you heard Nathan talked about the good wheat yields and we had excellent wheat yields and we had excellent pea yields and flax and those kind of things in the corn pretty well was a zero. Not not quite, but almost and the sorghum was pretty good. So the drought-tolerant corn was was quite a bit better, and he talked about that as well, and then the big thing is this thing we’re not going to read necessarily, but it’s an emphasis on rotation that talks why we use crop rotations. And it talks about different types of crop rotations. You know I’ll just summarize those real briefly, but you crop rotations much more important when you quit doing tillage. It’s the diversity that controls, and you you all got to watch Ada and you got to listen to Emmanual and Bob and they all talked about these things and it’s you didn’t see a lot of weeds out there. And we don’t spend lots of money on herbicides. You know we might spend on just under a 1000 acres we might spend somewhere between six and eight thousand dollars a year on all of our pesticides. It’s not a major part of what we do. We spend a lot of money in fertilizer because we sell a lot of product, but we try to control what we see technology and technology is a great thing but technology is something we want to use to help us manage our ecosystem better. Not something that we will use to try to keep the eco system from doing what it wants to. We want to augment those natural cycles, okay and what you’re trying to do in any farming system, anywhere in the world, is you’re trying to match if you’re going to be long-term sustainable, you have to match the natural vegetation in terms of how it cycles water, how it cycles nutrients, how it captures sunlight and carbon dioxide from the air and if you don’t do that, if you allow your system to leak, nutrients for instance out the bottom because you haven’t gone down and kept that nutrient from going deep or you let it go into a drain tile into the river. The Raccoon River at Des Moines by the way around 22 parts per million nitrate nitrogen this spring. Legal drinking water is ten parts per million. Okay. That just really not acceptable. We can do better than that with cover crops and all these things that that we’re trying to use, but it’s all part of a big picture. If if you don’t cycle those nutrients properly you turn into a desert. The soils degrade to the point where you become a desert. Think of think of Israel for instance when they came there, there’s land of milk and honey. Have you ever been to Israel? Its rocks and sand. Okay, because they turned it into that because of poor management, and so there’s all these civilizations that we’ve only been here. The United States and right in this area here probably homesteaded slightly over a 100 years ago and we’ve degraded the ecosystem appreciably in the last 100 years. Okay, so one of the things we’re trying to do is look at how can we better cycle things. I’m not so sure that we can do crop rotations without perennials and In cycle because you don’t ever have a deep root system to suck things up, so we’re going to go out look at some of those things. We talked here about different kinds of rotations, or simple rotations corn-soybean being one. Wheat-fallow being one. These are simple because they’re predictable in both sequence and interval. They’re always so many years, wheat- corn- soybeans would be one. They’re same sequence, same interval for that crop every time, so we’d always follow this piece. For instance okay, so that gets to be that’s one of them, then you can get more complex and one we used to talk about it Redfield was to do something like Wheat- corn- bean- corn- bean. So you’re getting a more complex. Now half of your corns into wheat stubble half your corns into bean stubble. I sometimes call these my mother-in-law rotations. If your mother-in-law comes to visit you this time of year and you go through these fields out here the the corn planted into the bean stubble or pea stubble was nice and big and looks great right and the stuff in the wheat stubble is kind of tall. She comes in June, I show her those. If she comes in late August. most of the time we’re gonna go to the one that was planted in the wheat stubble because it’s gonna have had the moisture. But what that does is it spreads your risk of wet and dry years. You got half your corn in in a situation where it’s gonna do good in the wet year and all of its going to do okay most years, but when you get these dry cycles. And then you can get, start getting more, more complex than that by adding like Nathan said sorghum instead of corn. In some of those things you’ll see some of that out there, where we’ll have sorghum- corn stacked one behind the other because you break a lot of disease cycles there but you still have kind of that look of corn in terms of high residue and how it uses water and what it’s used for and what the market is. And then the one that everybody maybe attributes to us is a thing called a stacked rotation and the stacked rotations are actually very similar what Mother Nature does because she’ll have a new. If you go look at any spot on the Prairie you’ll have a plant starts growing here, it’ll stay here a few years and then it’ll go away and some other species that come into that position and you’ll stay there a few years And it’ll go away. And it really comes down do what happens with diseases and insects especially, in that it takes them a while if they if the inoculum goes to very low levels. If we ask Emmanuel about the disease triangle he’s gonna say well you need to have inoculum, a host, and the right weather right? Disease triangle, so if you’ve had a very long break without a crop there, particular crop, it gets a certain disease then the first year kind of independent of the weather you’re going to pretty well have low disease because you don’t have the inoculum. Second year you may have disease if you had the right weather the first year. Let’s say wet weather. Well the probability having two wet years in a row appears pretty low so tt’s it’s not a bad trick to do that to do two wheats, but the secrets have in the low-low inoculant. If you do every other year Emmanuel would tell you you’ll have a lot of inoculum hanging around because it’ll last more than a year. The secrets having these really long breaks. It’s not the stacking that’s important, it’s a long break that’s important. So we’ll do, we started this with wheat- wheat-corn- broadleaf which you’ll see on the dry land because very very few people in room remember this but the old farm bill used to talk about base acres a farmer would have a 50% wheat base. That means he was allowed to grow wheat on half of his acres. You couldn’t grow any more wheat than that and so when we came here,we knew that we needed to knock down the inoculum without doing tillage so we needed a long break but they weren’t going to give up on 50% wheat so we’re better off with wheat-wheat, two years out of wheat and going wheat something wheat something. So corn, soybean, or wheat something or the worst rotation. And so we did spring wheat-winter wheat- corn- sunflower or soybean because again the farm program would allow guys to grow flax or sunflower and call it wheat. See and the old days the farm program just as stupid as it is now. And you can quote me on that. But anyway, that’s how we started in that that principle still applies and in just a couple things on stacked rotations, and we’ll go to the field but the other things it does and we got one on the irrigation. You’ll see which is is wheat- wheat- corn- corn -soybean- soybean. Well we get problems with insects for instance if we’re consistent in in sequence or interval. If you take corn rootworm as an example and Adais gone so you can’t correct me, but she won’t. If you take corn rootworm, their normal habit is to for the beetle to feed on the silks of the corn, lay its eggs at the base of plant. If you grow corn again the next year you get problems and that’s why we have BT rootworm corn which everybody grows and now we’re getting resistance to that. What happened in the Western Corn Belt including the eastern, South Dakota, they did corn-bean- corn- bean- and said we’re going to take care of the corn root worm by having corn-bean and we developed extended diapause corn rootworm beetle and now and what that means is that egg didn’t hatch for two years. It waited an extra year for the corn to come back okay because we were consistent in interval always two years out. In reality that female always laid eggs which mother nature will do. It’s like weed seeds some of them will hatch first year, some would hatch second year, maybe some hatched third year, and so they just got in synchrony with what we were allowing or doing, to do. In the Eastern Corn Belt they they developed the soybean variant. Where the the gravid or the pregnant female would fly to the soybean fields to lay her eggs because corn always followed soybeans so if you’re consistent in sequence or interval. If the guys here always planted corn behind wheat. We will develop a corn rootworm that will lay her eggs in wheat stubble. So one of the things we’re trying to do with something like a a wheat-wheat- corn- corn- bean- bean is to be inconsistent in both sequence and interval. The other thing is stack allows us to do is to utilize long residual herbicide programs. Like right now a lot of guys are just totally dependent on post emerge program. If you study ecology 101 the hardest time to control in unwanted species in the ecosystem is once it’s established. It’s at least vulnerable once that weed has started to grow and it’s there is when it’s least vulnerable to control. Its most vulnerable period as before the seed is produced, so that’s where we talked about sanitation, taking care of not let weeds go to seed and not digging up with high disturbance old weed seeds. And then with residual herbicides, you’re taken care of before it germinates. So with something like the first year corn in a corn on corn we can use products like Atrazine that we normally couldn’t use in a lot of our soils or low organic matter situations because you fear carry over to some susceptible crop to next year. By putting two corns or a sorghum before corn and that’s when we use it a lot you use a higher rate of Atrazine, that’s your weed control that year and the second year go ahead and use your Roundup Ready. That takes a lot of pressure off the Roundup Ready in that or the Roundup in terms of resistance because they’re not spraying the same product, on the same weeds, at the same time year after year after year. That’s really where you get resistance, okay. 1994 I predicted that Roundup was at a big Monsanto conference while I was a closing speaker, I I predicted Roundup resistance before Monsanto said it was going to happen. Simply because Mother Nature will do that to you if you get predictable. Now it also said, it’s not Monsanto’s responsibility to protect it, it’s the farmers responsibility to a better job of managing that technology, and that’s really what we need to do is manage our technology so we keep it. These companies aren’t going to keep developing new stuff all the time for us. There to say ah we’re gonna make more money someplace else. So anyway, that’s and I talked about all that stuff in here. That’s the Reader’s Digest condensed version of this. Let’s go to the field if you have no questions. We’ll just go to the field. (Music)

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