 I'm Dave Fransen, Professor of Soil Science and NDSU Extension Specialist at North Dakota State University, and this presentation is on our movement away from yield-based formulas and the logic and science behind it. The presentation is End of Yield-Based Fertilizer Recommendations and the end calculators. So the question on some people's mind is that the former nitrogen recommendations were yield-based and the formulas were pretty straightforward. The wheat one was 2.5 times yield goal, less credits like nitrate to two feet and previous crop credits. Then corn was for ages, decades, was 1.2 times yield goal, less the credits, and for sunflowers for 30, 40 years it's been 0.05 times yield goal and pounds per acre, and that was the formula. So why in the world would we want to get rid of that? Another thing that is really hard about this movement is that there's a psyche within farmers that's been taught since the earlier days that nitrogen recommendations are based on yield goals and I think maybe sometimes as I'm talking to growers that maybe the first or second story that their parents told them when they were very small went something like this. Once upon a time there were three little pigs and one day they were out in the field thinking about yield goals and then the story goes on from there. So that's how deeply embedded these formulas are in some people's mind. These are some concerns that I had even before we established these new recommendations and had the data set to support it is that having a formula like that of a some number times the yield goal makes farmers think that they can push the yield higher by using a higher end rate. That two and a half pounds of nitrogen equals one more bushela week. That 1.2 pounds more N equals one more bushela corn and that a twentieth of a pound of nitrogen equals one more pound of sunflower seed and that zero N equals zero yield and really that's not true. So what the formulas show is a linear relationship a 2.5 to 1 relationship or 1.2 to 1 relationship. So it kind of looks like this that the yield goes through zero zero on the left hand side there and then at some point your magic yield goal your Christmas wish your hope for the future that's when the plateaus out and no nitrogen apparently doesn't make any more yield and this is really just a fantasy. So this is what real data looks like this is all the data we accumulated the data that went into the wheat set well over a hundred site years of data modern data and data that had yields that are pretty comparable to the yields we had today that's what's in the set and over on the left we have the wheat yield and on the bottom we'll have the available land that's a total available land that includes the soil test nitrate two feet per previous crop credits if we know what they are. So the real relationship is that curve black line that goes through the middle of the quadratic curve the kind of relationship that we always see with soil fertility research and the yellow line which goes through zero zero and then up toward the top is the wheat line the two point five times yield goal and it it's not really related to the data at all doesn't doesn't explain anything about what's going on. Protein also which we is an economic portence to farmers of spring wheat Durham is also a quadratic curve and not a straight line. One of the things we do with all of our work with the wheat and the corn and the sunflower the three crops that we worked with the last what eight nine ten years something like that to modernize our recommendations to make them compatible with site specific agriculture is is take a look at the data without consideration for the soil test and there's a few sites in there also that have maybe soybeans or field peas or something as a previous crop and that's not considered in this data too so so this is what that data looks like there's a little bit of a relationship there but I want to call your attention to the very left side where no nitrogen is applied and yields go from around six bushels an acre to eighty three and if you can explain how that's possible with no and I would love to visit with you because it does make any sense at all. It only makes sense if you put the soil test in with it. So let's go back to the end of yield based formulas. The first research group that looked at data and decided that there really wasn't any relationship between nitrogen and something like expected yield that nitrogen was independent between sites but dependent within site was the group at Oklahoma State Bill Ron, Brian Arnell and they started tweaking this out somewhere around the late nineteen nineties two thousand when they were working on the green seeker there were the developers of the green seeker and they were the agronomy portion of the development of the green seeker and they found that if they tried to use the same algorithms with something like an expected yield it just didn't work that yield and nitrogen rate were independent between fields and so that's the reason that in our algorithms that we have the nitrogen rich strip always in the field is because you have to have an infield reference for adequate nitrogen that some formula describing everything doesn't really work. Starting around 2005 the Midwest Corn Belt States started working and recommending nitrogen rates for corn based on a return to nitrogen economic production function and we have used that now since 2010 and all of our modern recommendations for nitrogen are not only responsive yield and maybe quality in the case of spring wheat Durham to nitrogen rate but also the economic cost of that and those recommendations don't have yield in them at all either and so it's implied by Wisconsin and Illinois and Indiana and all the other states that use that return to nitrogen model is that they recognize that yield and nitrogen rate are independent between fields and the recommendations are not yield goal based. So the first people that came out with that idea that returned to nitrogen model were John Sawyer from Iowa State and Emerson Nafziger at Illinois are my counterparts in those states and that model integrates yield response to end with economics and the recommendations aren't yield goal. It assumes a grower is going for as much yield as economically practical. I have no idea why a grower would want to shoot for a hundred bushel an acre of corn in the eastern North Dakota that is making sense to me and so why not make recommendations that assume that they're going for as much as they can get. In certain states there are areas within the states that where the yield response is different than in other parts of the state and in those states they separate those areas out and we do the same thing with ours as you'll see as we go forward. So what does all this mean? So this is the background of all of our return to nitrogen recommendations and the ones from Iowa and Illinois. So the factor that affects the rate of nitrogen the most is the price that the growers will get for the commodity, in this case corn but the same principle also is used in our wheat recommendations and sunflower recommendations. So we have down here at the bottom an array of end rate curves with $3 corn and the middle one is $4 corn and the top one is $5 corn. So that array is made up of the cost of nitrogen within those data sets. And the peak of the curve here we have $5 corn and the top curve is always the low end rate in this end cost and in this suite of choices this is 20 cent end, 30 cent, 40 cent, 50 cent up to a dollar a pound for nitrogen and all of these nitrogen costs are costs that I've seen in the last 25 years. So these are all real costs. So the rate that's recommended at a cost of corn depends on the price of the nitrogen and it's the very peak of this curve which you can determine with a couple of rulers but most easily since we had a formula for this we just figured out mathematically what the maximum is here. You can do it with calculus. It's one of the reasons why I took it. So all of these numbers here that would equate to a nitrogen number down here at the bottom. So it's all the poor. And you can hope you appreciate that when you get down here to $3 corn when you start talking about nitrogen costs that are 70 cents, 80, 90 cents, a dollar a pound that the best choice is not to put any nitrogen on at all which makes people gas. But economically, farmers need to understand that the reason they put on fertilizer is to increase the profit and if they're not profitable doing it then why in the world are they doing it? It's not an exercise. It's an economic decision. We came out with nitrogen calculators web-based for wheat first and then for corn. And then in January 2015 we're about ready to really start getting down the field work had been done on our sunflower work. And my graduate student, Eric Schultz was given a presentation at the 2016 Soil on Soil Water Workshop which I put on at the dome. And then one of the front rows was an old colleague of mine a good friend and esteemed person who was the head agricultureist, American crystal sugar Al Katna and Al is looking through Eric's presentation and there were a lot of graphs that kind of looked like this that there was a relationship between the data and the curve but the relationship was pretty weak. This number here is going to come up a lot, this R squared. This R squared is the statistical relationship between the scatterer points and the curve or the line that describes it. In R squared of 1.0 which we never see in ag work is a perfect correlation perfect relationship. If we had a R squared of 1.0 all we would see would be that line because all of the points that were generated from that research would fall directly on that line. And then in R squared of 0 there would be no relationship at all we wouldn't be able to place a line there at all and this is pretty close to it isn't it? And it looks better when we start dividing it out by soil but this is what it looks like and so Dr. Katnault raised his hand and he said he'd just be really reluctant to make a recommendation for nitrogen based on data within R squared that low. And I started thinking about his comment and it bothered me because I knew that in almost every site that we had the data for each individual site the R squared, the relationship between the data and yield was very strong. I mean R squares of 0.5, 0.8 something like that sometimes. It was really strong but when you graft it all on one graph it just looked like this cloud and so there was a disconnect there and a failure of what we were doing at that time to describe what was actually going on between sites. And so I started thinking about why in the world that relationship of available nitrogen to yield was so diffuse relationships within the sites were so highly related. And so I started thinking about it like this and I'd like for you to think about it as well as we go through here and I'm going to try to convince you that this line of thinking is correct. So when we combine all the sites it kind of looks like that where we have this diffuse cloud and you can force a curve through it but the R squared is going to be very low the statistical relationship of the raw data with nitrogen is going to be very low. But really what we're looking at is something like that where we have a series of almost parallel quadratic curves stacked on top of each other from low yielding environments to the highest yielding environments. In each individual site the relationship is high but graph in the raw yield makes it look really poor. This idea came to mind because of something we use in site-specific agriculture. I strongly discourage farmers and their consultants from using a one-year yield map to help make zones for management site-specific nutrient management specifically of the field. What I rather see them do is to take multiple years of yield maps and then combine them together. But some years the yields even if you're using the same crop let's say that you're irrigating down at Oaks and you have corn every year but one year at the corn the top yield is 250 and the next year it's 200 and maybe you have a really poor year and it's 180 and then you have things in the middle so how in the world do you put those things together and have it make sense? And then a lot of people of course just don't grow one crop at least they shouldn't most of the time and so there'll be maybe 3 or 4 crops in a rotation and some like say sunflowers are going to be in pounds and acre and others are going to be in bushels and acre and even if you translated the corn into pounds and acre it's certainly going to be much higher than something like a canola crop or a soybean crop and they all have different pounds and acres that you take out of the soil and so how do you do that? Well you do it by normalization and this is what I mean here's an example from our sunflower data so we had a site that had a high yield within the data set of really it was over 4,000 but we'll just put 4,000 here for example and so what we do to normalize the data the same range of values as all the other fields is divide all of the yields in the data set by the highest yield here 4,000 pounds and when we get done we have values between 0 and 1 and then we have a site that for whatever reason it had a high yield within the plot of 1,800 pounds so we divide all the yields by 1,800 and again we end up with values between 0 and 1 and we have a sunflower site with those yields in the middle 2,500 pounds and we divide all the yields by 2,500 so again we end up with values between 0 and 1 so it doesn't matter what the high yield was within one of the data sets that's being put together at the end they all have values between 0 and 1 so that's what we do when we normalize so if nitrogen rate is independent of site and independent of expected yield then normalizing the yields at all of our sites is going to end up looking like that with the data collapsing upon the response curve and so it will look like that instead of the huge cloud we looked at before if I'm wrong and sites are important and the expected yield is important then the data is going to look like this like here's the low yielding site and when you increase down it's going to go up like this and here's the highest yielding site and so it's going to still look like a cloud when we get done it's not going to help it so that's what would happen after it was normalized if what I said is not true so let's take a look at our data for all our crops and see whether the sites are independent of yield or independent of nitrogen rate or not so here are western North Dakota the west river fields mostly conventional till wheat sites and the raw yield up in the upper left hand corner and we can scribe a quadratic curve and the r squared is low but it's still significant but the cloud is pretty diffuse isn't it so what happens when we normalize the data the right hand graph shows that when we normalize the data the r squared the relationship more than triples up to 0.53 the data is collapsing around the curve and is much more strongly related so western North Dakota no till wheat sites the raw yields again pretty low r squared 0.19 and again when we normalize them in the right hand figure the r squared again more than triples up to 0.62 it's collapsing around the curve how about eastern North Dakota wheat sites conventional till r squared a little bit better 0.31 still pretty diffuse but when we normalize them they almost double up to 0.58 so again they're collapsing around the curve and the no till wheat sites in the eastern North Dakota we start out with 0.26 in the raw yields and when we normalize them again the r squared increases not quite double but certainly it's a lot better relationship than what we had before so let's look at corn here's the eastern North Dakota high clay conventional till sites in the upper left the raw yields and the r squared is 0.22 which is fairly low and then when we normalize those sites the r squared goes up to 0.47 more than doubles and if we look at the eastern no till sites with corn raw yields r squared to 0.2 and when we normalize that data the r squared goes up to 0.68 more than triples and how about sunflowers western North Dakota no till sunflower sites raw yields 0.27 pretty diffuse and when we normalize the data they collapse around the curve and r squared goes up to 0.47 and how about the conventional sites in eastern North Dakota the raw yields are really low r squared to 0.14 and when we normalize those same sites the r squared about triples up to 0.41 so the only reason that can happen is that normalizing and the increase in the r squared telling us that the data is really what I thought it was a series of reasonably parallel quadratic curves they lay right on top of each other depending on the productivity of the site so these data that you just saw they indicate that the use of yield based nitrogen rate formulas should end and people should recognize that a profitable end rate in a low yielding environment is similar to the end rate that should be used in a higher yielding environment so this is hard for people to wrap their heads around how can this be possible how can the same end rate that's going to give you the highest yield slash profit in a low yielding environment be the same end rate that's going to give you high yield and profit in a high yielding environment so let me try to explain what I think is happening that makes this happen in a low yielding environment in North Dakota it's usually low yielding because of water either it's too dry or it's excessively wet we have these situations in the state almost every year someplace sometimes we oftentimes we have both so in a dry yielding environment a dry low yielding environment let me try to explain what's happening there nitrogen rate is not the only source of nitrogen that a crop sees generally the nitrogen use efficiency of any nitrogen we apply as a fertilizer is especially pre-plant or at planting is around 30% I know it's a shock because people think it all goes into the crop but it really doesn't in a conventional till system about 30% goes into the crop and the rest comes from someplace else well what's someplace else one of the sources of nitrogen for the crop is the mineralization the decomposition of organic matter and residues and the release of nitrogen that organic material rots when you're in a dry environment the microbes that make that work aren't very active they're largely dormant and so in a dry year the amount of nitrogen we get from mineralization is very low also the main mechanism for nitrogen to move to a plant root is through what we call mass flow nitrate is soluble and when there is soil water that soil water moves toward the plant because the plant is a pump and it's pumping water starting at the roots and then up through the leaves through the evaporation we call it transpiration through the leaves and so it's pumping out and so there's a potential difference between the roots and the soil and that vacuum if you want to think about it like that near the roots draws the water that's in the soil toward the plant root including the nitrate that's dissolved within it that's mass flow well if the soils are all dry much mass flow do you get like none and so that means that the nitrogen use efficiency of anything that you applied is much lower in a dry year than it is in something we would consider normal so let's take a look at what happens when it's wet when it's wet and the soil pores of the surface and near the surface are pretty well filled with water those microbes don't work that well in that situation also in addition we experience nitrogen losses if it's a loamy, sandy or soil and we get leaching losses below the rooting zone and if it's high clay soils especially in the eastern North Dakota but in rare occasions out west we get a process called denitrification where when the soil pores are full of water which is easy to do in a clay soil because the pores are so small that there are microbes that take nitrate and transform them to nitrogen gas and nitrous oxide happens they're completely gone for any kind of use by the plant so we have nitrogen losses we have low mineralization from the soil when the soil is really wet like that certainly there is mass flow but the problem with the roots is that usually in a real wet year which the wetness normally happens somewhere in the made through mid-June area sometimes longer than that is that the root systems are pretty shallow a lot of farmers have seen that consultants have taken the time to dig out plants and so even if it dries up the amount of root volume that those roots explore is greatly reduced compared to what they can do during what we might consider a normal year so the end result of a dry environment or an excessively wet environment is that it takes more nitrogen per unit yield bushels or pounds than it would in what we would consider a normal water year well this is the winter of 2017 and this is a great time to talk about high yielding environment except for the poor people up in northeast North Dakota that experienced deluge this past year the rest of the state the moisture was near ideal it wasn't too wet, it wasn't too dry we had outstanding yields in many places in the state I had nitrogen studies on wheat where the check plots went 70 bushels and the protein wasn't that bad I had check plots with low residual end on corn studies that went 180 bushels with no application of end I've never seen mineralization and release of nitrogen from the soil at that higher rate ever in my entire career here and anywhere else so when the moisture is near ideal not too wet, not too dry not extreme in temperature and certainly we didn't have the extremes this year that we do some years the mineralization is at its peak my guess is that in a lot of the state outside of northeast North Dakota the rates of end mineralization were 100-150 pounds of end per acre just unbelievable so that happens and it certainly supports higher yield, doesn't it? the other thing that happens is that there's enough moisture in the soil to support that mass flow that when the roots take up water and it's lost through the leaves that potential difference between the low water potential near the roots and the higher water content in the soil that there's a movement of water toward the roots with the nitrate and so the efficiency of any nitrogen that's in the soil is very high in addition there's no water logging or dryness in the soil that's going to restrict the root ball so the roots explore the maximum volume of soil possible so release of end from the soil is very high the efficiency of any nitrogen that's available is very high so the net result is it takes far less nitrogen per bushel or pound or unit of yield to grow a crop than it does in what we consider a normal year the net result of that apparently, based on our data is that the same rate of nitrogen to produce economic maximum yields in a low yielding environment is the same rate that's necessary to produce economic maximum yields in an ideal high yielding environment so all of our new fertilizer recommendations are not going to be yield based formulas the recommendations are going to be relative yield based and whenever possible there's going to be regional and soil differences that result in different relationships between nutrient and yield and these are going to be incorporated and have been incorporated into our recommendations all of our modern recommendations so we're moving on to the nitrogen calculators and we've divided the state up into these three zones so far and the biggest divide is between eastern North Dakota and western North Dakota the differences between these two areas I hope is intuitive that it tends to be more moist in the east and it tends to be a drier environment most years in the west also the soils in the east are sediments that are 10,000 years old or less and the sediments in western North Dakota are what we call residuals there are sediments from the rocks in place and a lot of those sediments are 65 million years old so there's differences between those two environments I get questions from time to time for people that are in say Ammons County, Burleigh County Minot and Minot especially because that line kind of goes right through the middle of Minot so how in the world if you're in that fuzzy area how do you decide if you're in the east and the west and I would suggest that you take a look at your county soil survey and where your fields are and there are two different soils that occur in eastern North Dakota and western North Dakota on the same landscape and in a hilltop and a slope environment in the eastern North Dakota the hilltops often are characterized or named abuse soil, B-U-S-E and the side slopes a lot of them are barns soils, B-A-R-N-E-S just like the county and those same landscapes hilltop slopes in western North Dakota they have different soil series that describe them on the hilltops you'll have a Zall Z-A-H-L and on the side slopes you'll have Williams like the county and so if you look in your say word county soil survey and you look at those soils on your soil survey and you see a lot of abuse barns then you're in eastern North Dakota because what's happening is that soil survey is telling you what the environment what the predominant environment has been climate-wise for about the past 1,000 years and if you see in your word soil survey that your soils now there you're dominated by Zall Williams then that soil survey is telling you that for the past 1,000 years you've been in more of a western North Dakota environment so that's how I'd handle it is look at the soil survey so then we have that unusual Langdon area up there and the reason why it's unusual is number one because from the very beginning the data from the Langdon area told us it was different and the second reason the reason that's different and the reason the data is different is that there's a lot of ground up shale in those soils it's almost impossible to take a soil probe out there put it into the ground and take it out and not see these little slivers of of gray flat stratified rock in it that's shale that soil is shallow to shale in that area it's mixed up in the soil and that shale contains high amounts of mineralizable ammonium within the shale so the reason that the inner rates are lower up there is that that soil acts like a slow release fertilizer just naturally so we have three regions so going to the North Dakota wheat nitrogen calculator again first thing we see when we pull up the web base calculator is the three areas and then if you're maybe in steel county you put eastern North Dakota and automatically it goes low productivity is defined as historic yields below 40 bushels medium from 41 to 60 and high productivity over 60 so I've just told you that these aren't yield base but the first thing we're doing is taking a look at historic yields why am I doing that well wheat's a little bit different than corn and sunflowers corn and sunflowers are usually going to be especially corn is going to be on the best soil within a farm it's not going to be on the poorer stuff and so wheat is kind of a crop that gets placed when you fit the rest of the puzzle together and say well what are we going to do about Hanna's farm I mean it's always kind of a tough farm I don't really want to put corn or soybeans there what do I do oh we'll just put wheat on it so there are some fields in the state that farmers are really happy when it hits 30-35 bushels because some ears it doesn't hit anything close to that and I think wheat is really our only crop we have that great range of historical yields because you'll put wheat anywhere where you'll be more selective where you put some other crops so the productivity is in there for economic reasons not because of the response of the crop to nitrogen so you choose the productivity and then you can choose the previous crop that you plant and if it's an annual legume or if it's a sugar beet with different color leaves or if you're taking out alfalfa and putting it down so you click on those so those are important then over here on the left we select the wheat price toggle up and down select the nearest nitrogen cost you toggle up and down gives you kind of a preview you put in the soil test nitrate to two feet and then up here you put in whether the field is conventionally tilled or if you've been in no-till from one to five years or if the field is long-term continuous no-till then you could click that one put in the organic matter but that really doesn't change anything until you get to six percent the organic matter is going into the general productivity of the soil and being swallowed up on that probably part of the reason why we see that high yielding in sites don't need any more nitrogen because the organic matter is putting that in it's unusual to have a field or part of a field that has an organic matter one percent being a really high yielding field but it's more common for a high part of a field to be higher organic matter doesn't it so that's probably another part of the reason why we don't have yield differences nitrogen rate differences between differences and yield within fields between fields so we get to the end we have the nitrogen recommendation and we have a plus and minus 30 pounds there because I don't know everything about Grover's Farm these come from over 100 sites of data for the corn and the wheat 30-some sites with the sunflowers so there are many fields I don't know anything about so we rely on the growers and their consultants to have some common sense and this is the point where we exercise it and if they need it they have our professional license to increase it or decrease it based on with wheat especially say protein there are some varieties that will give you 14% protein almost every time and then there are some varieties usually the really high yielding varieties but not necessarily that struggle to hit that 14% and they may need an extra n so that's why that plus or minus so I kind of skipped over that that no-till, why did we put that in there? that comes from a conversation I had with the original long-term no-till people in the state back in, it was either the winter of 1995 pretty sure it was at the Manitoba North Dakota Zero-Till Conference and all the original no-tillers the Beach Boys you know people from South Central North Dakota and Northwest North Dakota people have been no-tilling at that time for well over 20 years and they told me that they were happy to see me but then they also told me that they didn't follow NDSU nitrogen recommendations anymore and I asked them why and they said that after they'd been in no-till for a series of years they found they could start cutting their nitrogen rates and they now had cut them to the point where the NDSU recommendations are 2.5 times yield goal that didn't make any sense for them anymore so in 2009 2010 when I was sitting down with that data set of over 100 sites I thought about that conversation and I had sites West River and East River that were long-term no-till and some of them were conventional till and so I thought well I wonder so I divided them up and they were right for example here the conventional till to hit 50 bushels around 150 pounds of N they had 150 bushels here in the to hit 50 bushels in the in the no-till wheat it takes 150 pounds of N or less and the same with the protein took 50 pounds of N less N to produce equal or better usually better protein than conventional till so we've looked at that in corn we've deliberately put out sites in long-term no-till fields in corn and when we went to sunflowers and the same principle applies to each in the wheat we have a no-till credit that comes off the calculator with the corn and the sunflowers just a different recommendation curve but the end point is is that the long-term no-till is way more efficient in nitrogen use than conventional till so why do I think this happens there's some background evidence of what I'm saying here and it just makes sense to me first thing people think of as well than the long-term no-till has more organic matter but that's not necessarily so there's five and a half percent organic matter soils in the valley for example than in a year only released maybe 30-40 pounds of N per year so it's not it's not the organic matter that's pouring out nitrogen what I think is happening is this in both conventional till and in long-term no-till there are microbes that are in the soil the microbes that are in conventional till have been selected for those organisms that when residue is incorporated they burn up the residue very fast they decompose it very fast and then they're just kind of gone they're dormant until the next flush of the residue comes nitrogen is as limiting to micro growth and reproduction as it is to crops so when we apply nitrogen to soil some of it's being absorbed, taken up if you will by microorganisms and some lingers in the soil and hopefully is there when the crops need it so if you put nitrogen in conventional till there is some biology there that's going to take up some nitrogen but most of the nitrogen is going to change the nitrate within a couple three weeks after application is just going to sit there as inorganic and any bad thing that comes along excessive water usually is either going to release out in leaching and loss below the root zone or in the higher clay soils it's going to result in the denitrification gaseous loss of nitrogen but in no till there are there are more organisms there's a greater variety of organisms from little things to big things and there are also many more of them and so when we put on nitrogen in a long term no till system there may be a little bit of free nitrate there but a lot of that nitrogen I think is taken up by microorganisms and that's important because microorganisms the life cycle often is measured in days and weeks and so there are organisms that continually die they decay, they release the nitrates taken up by more microorganisms or later on in the season after about 30 days or so then the crop has taken up significant amounts and so it's able to utilize that and that's one of the reasons I think why in the long term no till it's a lot easier to achieve a 14% protein and wheat than it is conventional till because the microorganisms seem to act like a slow release fertilizer so it's not that we don't get some leaching loss or some denitrification from long term no till but the amount that we lose is far less in the same environment than a conventional till so I think our nitrogen credit comes from just a higher efficiency of nitrogen use in conventional till we have say 30% nitrogen use efficiency and we're able to bump it up to say 50% which I think is likely in a long term no till environment that's certainly enough in order to to create that or produce that nitrogen credit that we give long term no till because our data tells us that we need to do so so this is our core nitrogen calculator we don't have something carved out for laying because there's not that much corn up there and we have no data but I would suggest that people to do try to grow corn up there as are useful corn varieties, corn hybrids become what, lower day and lower day which tends to be happening that consider a nitrogen credit for being up in the Langdon area too so we click either west river or east river the conventional till irrigated corn, no till corn they're separate databases that support all of those we're in conventional till in the east then we have no till for one to five years but we also have high clay soils with historic yields above 160 or less than 160 and then we have medium texture what does that mean 35% clay or higher anything from say a bearden soil onward, most of these soils are going to be fargos or vikings or hagg knees or something like that but anything from a bearden upward 35% clay or more and then the medium clay soils is kind of a catch-all so anything that's not medium or high clay is a medium textured soil a silt loam, a loam sandy loam, loamy sands textured soil basket we divide it out in the yields and the reason for that is that there are some soils that have internal drainage that's good enough to support those really high yields without doing anything special as with application of in but then we have fields that struggle because of their internal drainage particularly during wet years and the the yield struggle to get much above 120 bushels an acre in the same with the medium textured soils there's enough leaching in some of these wet years that it's a real struggle to hit 100 bushels an acre so that's a cue for people that have those kind of soils to not just think about rate but think about timing those are the soils that would probably benefit from a split application of nitrogen, a side dress or a hydrogen application so then it's an economic production function so we put in the nearest corn price nearest nitrogen cost the soil test the two feet the organic matter in the soil previous crop credit over here and the nitrogen recommendation plus or minus 30 pounds an acre again to take advantage of a grower common sense then the sunflower nitrogen calculator that's the one that is the newest came out just about a year and a half ago we have a Langdon area up here because there are sunflowers growing up there mostly convections so it has a different data set sunflower pricing nitrogen cost percent and an organic matter in the soil then I trade to two feet and then the tillage conventional till and then the oil seed and conventional till or convention there are different response curves long term no till again and then the short term no till so this is one nitrogen rate this is substantially lower and this is a little bit higher rate than the conventional till because some of that nitrogen has been tied up into decomposition of residues until you hit that magic five, six years, seven year time period when the biology is in full swing previous crop credits and then the nitrogen recommendations so those are all available as a web based nitrogen calculator to get there just search for Dave Frans and NDSU a source of all soil fertility information that you really need to know in this region and in the upper right hand corner there's three calculators the corn, the wheat and the sunflowers so you can click on those just like I explained to you but in this world of everybody doing everything on phones I was able to have my wonderful technician Honggang Bu program these phone apps so we have a phone app for Android and we also have one for iPhones so you can just go to the app store for each of those phones and look up North Dakota crop nitrogen calculator click on that and follow the instructions it's free, download and ready to go so yield goal rest in peace there is no reason to have yield goal recommendations anymore and use the nitrogen calculators and I thank you for your attention