Shrinking Grid Size To Diagnose A Soil Problem
26 Oct 2224 min 17 sec

In the past decade or two, soil sampling evolved from pulling a few plugs of dirt from each field to doing so on a grid. Grid sampling — if you’re unfamiliar — means gridding your field into blocks of 5 acre or even 2.5 acres. The more samples from each field, the better to more accurately prescribe your crop inputs. But sometimes dividing your field into 2.5 acre chunks isn’t small enough to straighten out a stubborn problem. Agronomist Robb Dedman and Layne Miles of Miles Farms explain why they sometimes shrink their soil samples to 1 acre blocks in order to diagnose yield problems for which they can’t seem to find the culprit.

Presented by Advanced Drainage Systems with support from Agricen.

00:00 Today we're talking to Rob Deadman and Lane miles down and McGee Arkansas about how to shrink your grid size 00:06 for more accurate and more importantly to diagnose soil problems. Welcome to extreme AGS cutting the 00:14 curved podcast where you get a guaranteed return on investment of your time as we cut your learning curve with the information. You can apply to your farming 00:23 operation immediately extreme AG, we've already made the mistakes so you don't have to managing. Your Farm's Water Resources is 00:32 a critical component to a successful and sustainable farming operation Advanced Drainage Systems helps Farmers, just like you increase 00:41 their yields up to 30% with their technologically advanced Water Management products visit ads to see 00:50 how they can keep your business flowing. Now, here's your host Damien Mason. Hey there welcome to extremex cutting the curve here 00:59 about soil sampling. You probably do it on your farm. You know, we've been doing it since the 1950s. The thing is starting a few years ago. 01:05 We started getting better at it and we started getting more concise and precise Rob's gonna explain to us how they 01:12 go about soil sampling in Miles farms and even with the companies in the Farms that he serves with ultimate AG Consulting and also how to then 01:21 shrink that grid size down to make it to where you really are dialing in and with a rifle approach to fix a problem. That's on 01:30 your farm. All right, Rob and Lane. Thanks for being here in the old days. We started slow sampling 50 60 80 years ago, whatever. It was go out there on the 01:39 soil probe throw some stuff in a bag send it off to a lab and say that field looks like this and then we said wait a minute that feels 01:45 80 acres and we just went out and pulled one soil sample. That's not adequate. When did we start doing a grid sampling? 01:53 last 20 years Yeah, so I'm gonna say in the last 20 years, you know, that's probably the the very early days of it 02:01 and here on the farm. We actually started in 2013 grid sampling. Because when we started here, okay, and that's 02:10 probably pretty normal. I mean that's there's probably some Farms are still don't do it. So tell me what a grid sampling looks like to somebody 02:16 that maybe doesn't quite practice it yet digging dirt including the Box. so 02:25 So a Funny Story start that with us in 2013 Lane was a senior in school and his dad made him go work with me during spring break. 02:35 And and we were pulling grid soil samples and we were pulling them in rice fields. So in Arkansas and March and rice field, you can only imagine 02:44 that those glycles are pretty sticky and kind of nasty muddy. And Line work with me a couple of days and he 02:52 went home and his dad said well, what'd you learn? And he said nothing. So all I do is dig dark stick it 02:58 in a box. so that was lines first impression of getting a grid sample, but 03:04 you know grid sampling is basically we we take the computer. We have a an aerial image of the field. We overlay 03:14 a a grid on top of it to the specified size of what we want to be. and and on this Farm we we've gone from you 03:25 know big to little and even smaller And you know, so we started out at two and a half. I didn't like what we were getting on Two and a Half didn't still 03:37 like we were getting enough. if definition in our in the maps of where the real problems lied at We Shrunk them down to two acre grids 03:49 and we started picking up the definition because we were getting 20% more data points, here's how 03:55 I kind of like to look at it and I know that I'm going back and probably dating myself to the younger generation but 04:01 You went to like shop class and they did drafting and they maybe gave you what they called graph paper. Right? And so I mean to the person that says what the 04:10 heck you even talking about on this so I always imagine taking that graph paper and which is just a bunch of squares and 04:16 then laying it over a map of your field and that's to me how you look at grid sampling and this is a matter of 04:22 this one's got bigger squares and wait a minute. We need to get a little more refined on this we make smaller squares because then we 04:31 start off with five acres was, you know, five acre grids. We're kind of the first thing weren't they? Oh, yeah, five and 10. I agree. It's what let out, you know, and they're 04:40 still a lot of people that do that and you think about it. We think about Rob that still is way better than just going out and grabbing one piece of sample from oh, you know 160 04:49 acre field. So if you start saying, okay now imagine we got 10 every 10 acres. We're gonna do this. 04:57 I guess it didn't have as much application until we got variable rate technology. Isn't that kind of what drove it because in the old days it wouldn't have mattered. Okay 05:06 over there lays wet over there. It's got really good organic matter and down. There's a clean knob but it don't matter. We can't 05:12 we can't vary what we do with our treatments. Anyhow. You did really good job when you weren't so judging didn't you? 05:19 Anyway, go ahead. I know you like to rub it in that you're the guy that's the grounding guy and I'm just the one to be. 05:26 so, you know that you're right when this thing started people were looking at this and be grids and and because in the beginning this was 05:35 expensive, it was an expensive process to work with so people were trying to minimize the cost break or 05:42 But in science in order to make good good scientific decisions in Grain Marketing in order to make good marketing decisions. 05:51 You need data points to reference. And and that's where the grid sampling in order to make good decisions on what fertility to do on a field. 06:00 We need more data points more data points better decisions. And and that's why we are today, you know 06:07 as technology and application called up grid sampling got more popular right probably started. 06:16 With being able to variable rate apply line we were with that caught on probably first. Where we used to say, well that field needs two times a 06:27 line. Yeah, and now we go out there and say well that that two acres needs two tons and everything else needs a 06:33 ton. You know, we we just saved the farmer a lot of money. I don't like Farmers to think that grid sampling 06:40 is definitely a a money saving Adventure because a lot of times it's gonna be equal to sometimes it's going to be more expensive than than 06:49 just going out there and put something out there. So Elaine answered me this we said we're going to do shrinking grid size to diagnosis soil problem. You 06:58 just heard the history from people like Rob and I our age that in the old days you didn't even do this. You came out you what 07:04 time you were out of high school grid sampling was the norm at least at Miles farms and 07:09 tell me about a problem that you discovered that or Rob and you all when he was giving you your internship out there picking up dirt and putting in a 07:18 box. What did you learn or what problem did you think do you think that you solved by by diagnosing it 07:24 on a smaller grid size. Oh the the story that he gave actually it's it's pretty funny. You know, we use that as a as kind of comic 07:33 all the time. But you know as far as far as what I what I learned the end didn't realize that I was learning was just just a study of souls. I mean now looking 07:42 back sometimes sometimes those two and a half agree that we were pulling. Like Rob said, it's not enough. It's not enough data. I mean, we we 07:51 have diagnosed he's gonna pull one up here shortly. But but that's one of many and we've diagnosed several problems that were like, all right. We've got a problem. 08:00 We may go in and Sample it again on those smaller grids just to see exactly how bad the problem is how far you know, if it just say 08:09 you have a 20 acre spot. That's that you've done on Two and a Half agrees or used to for round numbers. You know, you got it samples in there. Well, it 08:19 may show two thirds of the field that That's got to have this problem diagnosed. Well we go and do it on a on an acre grid and you're pulling 20 samples 08:27 out of it really and truly. It's there's a it's a lot smaller spot. And a lot more defined of well, there's 08:34 more fertilizing it goes here or too much or whatever. So from the time or when I was sampling didn't realize I was even learning anything. 08:43 I mean I I can't tell you what I've learned just as far as those as getting the data back pulling 08:51 it up all of us going over and over that big screen TV. You know, what what's wrong with this field? What what are we doing to it? And what do we need to do to improve 09:00 it? Oh, I mean in really and truly it it may cost a little bit more to get it on a more condensed. 09:09 more data points map but but the money you save and like Rob said in the in the set Line application where you were going to do 20 09:18 acres. Well now you're only done 10. Well you paid for your soul samples just in savings of line not including your savings in time diesel labor. Yeah work 09:27 and tear the whole nine yards. So the thing is like the person that says hey, I'm doing good sampling. I'm doing on fives and then you'd say we'll go to two and a half and they say that's gonna cost me twice as 09:38 much and then you'd say Rob. but you know it it didn't and you know, because what happened is 09:47 is the people that were doing the sampling realized that what they were giving back for what they were charging. 09:57 Was not what what the farmer needed and and did it go up a little bit. Yeah sure. It went up a little bit but it didn't really double in price and but I 10:06 think I think the the the more data you can get. You're getting a bigger value for your dollar. So you can also you're using less product because there's lots of times we were over 10:17 applying and when we just went through this last year we're fertilizer was doubled. Did you back off in some areas? Because your grid 10:23 told you you didn't have to Oh, absolutely. I'll let Lane talk about that a little bit because yeah, we did a whole different approach on this Farm. Well and 10:31 on that, I mean Damien we We feel like we do we've done a pretty good job on keeping our souls where they're supposed to be. Yeah, it put back what you took all 10:42 In that put back of what we took off their there's always been a build. Okay, so when we take off and we apply our 10:50 litter which is a blanket application because liters of real variable fertilizer. Oh. 10:57 You know our put back was mostly the build. I mean for the majority it was mostly the deal. So say say a hundred pounds was going across a 80 acre 11:07 field and you were going over. 48ers of it, you know half of it well now we only may go over 10 or 20 acres 11:15 of it because those are the 10 or 20 acre spots that needed the putback not the build so you can hold 11:21 your build back put back what you had keep what you had from last year and eliminate the building in a in a in a year that building is expensive. 11:30 It's kind of build a house. You didn't build your house because Lumber went up you waited a couple years Lumbers coming back down song. So 11:36 you start building houses again. Yeah. So the point is there's times to to use more on times 11:42 use less. I want to get into a problem that you fixed and I want to talk about where you shrunk a shrunk it down to an acre grid size 11:48 to fix a problem for do that. We're here quick word from our friends at agerson. Farmers you can't afford to waste your fertilizer investment. 11:57 But if your crops aren't utilizing the fertility that you've applied you're doing just that Innovative biocatalyst products from agerson that are available exclusively from 12:07 nutrient AG Solutions can help you get more bang for your fertility Buck by making nutrients more available to your crop. They help you get more out of 12:16 your fertility investment contact your local nutrient AG Solutions crop Consultants to learn more. All right. We're back talking to Rob Deadman Almanac 12:26 Consulting and Lane miles Farms McGee Arkansas. I'm holding a map and now dear listener if you want if you're listening to the audio you want 12:35 to see this. We're putting up the graphics on the video. So you can see this if you happen to me just listening to the audio because I think it's pretty illustrative to see 12:44 this. They got a 47 acre field. It's across the street from the Chickasaw church. I think is Chickasaw about this church. And and you 12:54 guys shrunk it down to doing one acres and I'm holding up the image. And again if you're watching you can see it, but it's pretty interesting. It's a narrow. 13:03 It's a narrow 47 acre field, right and they went and and did every acre. So you stronger for five to two and a half acres 13:13 down to one Acres you did that because of why So so the purpose on that was is we see and I you've got the the yield map. I don't know if you can show 13:23 it or not, but when we harvested that field. We had a I'm holding up a copy of it. But again, we're putting the graphic up right now, right we 13:33 have it's pretty telling it looks like in the North about the North. 13:40 Central to Northwest area you got a problem. He got a problem. Yeah. And we saw that we saw it in the 13:49 crop. We saw it throughout the the season. We saw it on the yellow map. And immediately we went back in there 13:55 and we said we've got identify the problem and we we looked at it on, you know, we went to the previous soil samples and two 14:04 and a half and and we did not find it. So we immediately went to one's and is as the the map show. 14:13 We defined the area perfectly on the nutrient deficiency that was going on in the crop that gave us the ability to to correct 14:22 it that that particular field is interesting because I was probably one of the first ones we did that was in 2018 that we 14:31 are probably one of the first fields that we actually shrink down to a one acre grid to help Define problems. Okay. So 14:37 here's what here's what's interesting to me. I just circled and I mean Grand this is rudimentary, but I just circled the 14:43 area based on your what Your combine yield map showed where the problem is and even on One Acres. I just circled if you it's about 14:53 Plot points. Okay. So seven to eight plot points that are where that problem is. If you were not doing grids you would have never known your lazy. You're 15:02 lazy guy from the co-op would have gone out there and stepped out of his truck and pull a sample up here by the road. Right? So we you know the old days so now 15:11 we go to now we're doing grits, but if you were doing five acre grids You would have not been able to dial that in. Like I said, I've got 15:19 seven plot points within where the problem is and I'm seven plot points. Now you really know what you're dealing with. So 15:25 that's I think a great illustration right there you and I mean on that picture, I mean if you just say you're doing it on on a five eight degrees 15:34 and that's a seven acre spot. Well, if you haven't hit it on a corner of that spot where where it might have been pretty good, but you never figured 15:43 that out, right? Yeah, in other words on a five acre grid sample. You're still doing better than than not grid sampling at all. But yeah with seven acres of 15:52 problem. You could be one of your sample points could be in a corner and you're not even getting it now. Here's the thing. The farmers gonna say I remember when we did here on my farm. 16:03 I think I paid six dollars per per polls. That sound right? I'm just thinking here what I paid for. So if we went from you know, 16:12 if you go to where you're doing twice as many, you know, six bucks you start putting that over even this this field 16:18 right here, you know, that's six bucks on what 50 acres, you know, three hundred dollars right there. 16:24 But Seven Acres, that's a real real problem. You can probably make that 300 bucks back with one good Bush one good acre of corn. 16:33 Right? Well you make it back with one good acre of corn. You can make it back with let you know one fourth 16:39 of a ton of fertilizer. I mean we're talking about You know 500 pounds of fertilizer in today's market. It's really easy to make that money 16:49 back. And and to to see that return on that investment, okay, so then the person's gonna say maybe we should do acre grids across all of our 16:59 Acres your response would be Lane. I mean if you want to Great does it necessarily necessary? Probably 17:08 not right? I mean we do we do half of our farm every other year on two and a half acre grits and that right two two. So 17:17 who's onto any if you see the problem? Then go back and and get your acre grids. I mean if you say okay, I've got a problem. I could tell 17:27 there's a little bit of a problem. Let's see what let's see. If it's worse. Then you might only go do less than a hundred acres or 17:33 three or four field or something like that. Yeah. So the cool thing I just heard there is it's every other year. It's two acre grids to the point is is you're 17:42 never more than two years away from an accurate soil sample, and then you transpose that against that yield map 17:48 like that picture you you had here which we're putting up of the yield map. You say wait a minute. We got a problem. The combine showed 17:57 us here. We're in the red on that spot and then you can start diagnosing. How many times have you shrunk it down to one acre Rob? Oh gosh 18:03 a bunch. You know a bunch, but I mean not Bunch really because like just like this year. I mean, I'm doing a bunch. 18:14 And I say a bunch I'm doing we've done over a thousand acres this year so far what we pulled on acre and a half. Okay, really 18:20 see didn't need to really see and that's what I tell customers. When I go to a customer and I 18:28 start sole sampling. You know, I'm gonna tell them okay, we're gonna sell you, you know, and it's a service that you sell I'm selling 18:36 you to acre grids and but I'm gonna reserve the right to go down to whatever I choose. 18:44 You know some of that's on me some of that's gonna be on you depending on what we're looking for and the 18:50 make a lot of those determinations after kind of talking to the customer, you know, well feel about 18:56 field one over there in the northwest corner. It only yielded 20 bushel, but everywhere else that yielded, you know 200 and so 19:05 what I start trying to do is and you can look at these fields even after harvest you can look at Crop residue and stuff like that where you don't 19:15 have crop residue you had a problem we get it. And you can look at a field and said man. I need to really do that one on one and then you shrink it 19:24 down. So there's a real good example. You said we're doing a ton and then Lane says no you didn't well, okay on 11,000 19:30 Acres you did it on a thousand. So that's still about you know, what nine percent of your Acres, but that's not that many. It's just that you did it 19:39 that way because you you're in and I had asked the question and outline I sent you how did you know you even needing to do this again it goes back to yield map 19:48 from the combine, right? It does our good. Well. Well, I mean a lot of times, you know, say Rob's gonna run a two agreeable 19:57 we cut a field and we know what Charles bullet called me on the phone. Hey, man, the west side of this field looks pretty tough. 20:06 Of send me the yield map. Well, you know, I'm at the green beans run the dryer stop pull the yield back up but yield map up send it to him now. Stop 20:15 my looking like. All right, man, did this is but that's I'll send it to Rob and you know, there were we make the decision on whether or not 20:23 we need that acre. Grid right there at the time. It was gonna get two acre but we now we changed it the one yeah, so you can you make 20:29 the decision when it's fresh in other words. Let's not let's not wait and we get through and all this initial like hey what we decide we're 20:35 going to do you basically do it when you see yield results you make the decision right then. 20:39 Yeah, we're calling on Audible on the go. What about and if you don't need to call the audible, can you make the audible and say we know we got a problem based on our yield map, 20:48 but we also know this field was underwater. I mean there's some times it's not about grips. Yeah, that's right. You asked me to print this off and then we're gonna put 20:59 up the graphic P for corn 200. What am I looking at? Is that same field? So the key to that is is if you look at the the map you see that big blue spot. Yeah, 21:08 don't take that and you don't know. Yeah right there. Hey, you found that back to the to the yield map. It shows you that 21:17 there was our problem. We had a foster to Patient see in that field. Okay when we corrected that. It went away now to tie into 21:26 one of our other companies where you talked about agrotech where it wasn't a phosphorus deficiency as a phosphorus uptake issue ability was 21:32 it was it availability or was it would not even there? Uh that particular field it was too low. Okay, we see you fix it like that. All right. So Lane and 21:43 Rob big question here. The person that says, okay. When should I shrink my grid down? I'm already sold on doing grid soil sampling and I'm starting 21:52 with five acres. Just what I can afford. I'm going to twos like you guys whatever your recommendation is. 21:58 Do it every other year you do it on two acres and then they say, okay. I think I got a problem over here in the in the the Smith Farm. 22:07 So, you know the farmer knows what he's got a field he knows the field didn't grow right he knows it didn't something happened out there. He's got 22:16 to be the one to tell me if I'm not the one that's scouting the field tell me that hey, I've got a bigger problem out here. I don't think we can define it. 22:26 Let's then let's move it down to the one acre grids. Let's get it real to find soil sample map 22:32 with results and and see if we can make it match up to the yield map. Lane the person that says yeah, 22:39 I think maybe I should be doing smaller grid size. You say don't do it. I don't go crazy. Don't need to do it on one Acres all the time. You do it when the yield 22:48 map tells you to and then your recommendation from there is what oh, you know, if you definitely look 22:54 at your Maps your own fives and you absolutely know that you don't want to go down to to ones. You 23:00 don't want to spend the little that extra money come in half go to two and a half just get a few more day to points. Yeah, and 23:06 then if you ever had a mistake or anything you did wrong like you had too much information say it. Oh man, you know 23:15 what this was more than we needed you ever regretted shrinking your grid size to fix a problem. I guess is the question. There's 23:21 no such thing as too much information. Or I like it. Alright, his name is Lane miles. He's sitting next to Alderman act Consulting and Miles Farm 23:30 apart business partner Rob Deadman, I'm Damian Mason. Thank you for being here for Extreme Ice cutting the curve till next time share this with somebody, you know that can 23:39 benefit on from fixing a problem. And then way to do so is by sometimes shrinking your grid size and your soil sandwiches till next time that's a wrap for this episode of 23:48 cutting the curve, but there's plenty more check out where you can find past episodes instructional videos and articles to 23:57 help you squeeze more profit out of your farm cutting. The curve is brought to you by Advanced Drainage Systems the leader in agriculture 24:06 Water Management Solutions.