Soil Fertility and Testing

February 17, 2021

Video Transcript

- All right, well, the time is 12 Eastern Standard, so let's go ahead and get started. Good afternoon, everybody. Please note this session is gonna be recorded. But welcome to the "Michigan Ag Ideas to Grow With" virtual conference. Should you choose to leave your video on, be aware it may appear in the recording. Recordings for this session will be posted a few weeks after the conference, and we ask that you please remain muted throughout the presentation. We'll have some time at the end where Mike can address your questions, okay? My name is Christopher Imler. I'm a Horticulture Educator for Southwest Michigan. I'm based in Kalamazoo. It's my pleasure to welcome you to this session, "The Soil Fertility and Testing" session. Today, we're gonna hear from Mike Staton, a Field Crop Educator with MSU Extension. This session is eligible for RUP credits and CCA credits. I'm gonna put some information up on the screen now, okay? If you're interested in receiving credits, please ensure that your name in Zoom includes your first or last name. You can also message me privately if you don't wanna include that. This is how we verify who has attended the sessions, and this is how we verify who can receive credit for RUP at the end. Please note that you need to be on for the entire session to receive RUP credits. Because at the end of the session, I'm gonna share a link for evaluation that is required for your RUP credits, okay? Please note that if you have any youth audience in attendance, or if you are, yourself, are a young learner, we do have scholarship opportunities that are available. I'll include this link in the chat at the end of the session as well. We also just want to thank our sponsors who made this conference possible through their generous donations, found here. Okay, now, as part of this conference, MSU Extension has put together some short videos that are related to food safety, which is a particularly relevant topic at the time that we'd like to share with you. So I'm gonna get this popped open, and we can play that now before we start the formal presentation. - [Narrator] Most everybody that grows or handles apples knows that apples float. You know what else floats? Deer poop. Believe it or not, deer poop can get near apples like this. If you're an apple grower, you've likely staged your apple bins in the field to fill with apples. Conscientious apple growers have someone walk the rows where the bins are staged to mark areas where there are piles of deer poop. The person who stages the boxes usually avoids these marked areas to put boxes on. If you're an apple handler and processor, you likely submerge the bin and float the apples through your line. A poopy bin bottom would be the first thing to hit your dunk tank. That poop would likely float to the top and move through the line with the apples. Once poop enters the dunk tank and touches fruit, no amount of sanitizer can clean it off. Scout rows where bins will be staged for deer poop. Keep poop off food. - Okay, so some succinct messaging from our MSU Extension Food Safety colleagues. Hope you enjoyed that. Okay, so let's jump into today's presentation. If you have any questions during Mike's presentation, please type them into the chat. I'll bring them up at a relevant opportunity. That way, we can move at an even clip, and we can hear everything that Mike has to say about soil testing. Whoops, here we go. Okay, Mike, I'm gonna go ahead and let you grab the screen. If you're just now joining us, I just wanna reiterate, we are recording the session. So if you choose to leave your video on, you may be included in the recording. - [Mike] I really appreciate the opportunity to be here. I am Mike Staton. I am a Soybean Educator with MSU Extension and have been doing that for, oh, probably the last 12 years. And I used to teach Master Gardeners Soil section, but it's been a good 12 years since I've done that. And basic soil fertility and soil testing, we have some really good information from the University on this subject, and I'm basically gonna use the Master Gardener Soil chapter as my basis for this. But before I do that, I wanna talk about this slide. This is really important. It basically, all these beautiful words say that everything that the University does is available to everyone. And that's, of course, the way we would all like it to be. So I wanna start with some basics here of soil chemistry, because it kinda builds on each other. It's hard to understand fertilizers and fertility unless we understand these basics. But one of the most important things is just that atom is the very smallest property, very smallest substance that contains all the properties of that substance. There's usually no net charge, and behaves kind of like our solar system. If you look at this diagram to the right, it kind of, the electron is rotating around the nucleus, which contains the proton and the neutron. Why is that important? Well, atoms build molecules, and molecules are very important to soil fertility. So what happens is a molecule is basically a group of atoms, like water, that's just bound together by some bonds. Typically, a molecule doesn't have any net electric charge. And that electric charge is important, and we'll talk about that. Now, an ion is an atom or a molecule that has an electric charge. It's either gained an electron or lost an electron. And that gives it either a plus or a negative charge. And that becomes increasingly important to soil fertility. Here's the reason. We have some cations and anions. Cations are positively-charged ions, anions are negatively-charged ions. And both are taken up by our plants. We have nutrients that are cations, we have nutrients that are anions, and they're both taken up by our plants. Where it gets to be important is, the next slide will show you why whether we have a positive charge or a negative charge on our nutrients is important. We have, basic concepts is that like charges repel each other, and unlike charges will attract each other. And that gets to be really important. And this is why. Clay, an organic matter, all have negative charges. They both have negative charges. The soil has negative charges. Now, sand and silt are neutral. They have no charge. But clay and organic matter do. And you can see that as represented here. The dark-colored humus has these negative charges. Why is that important? Well, the negative attracts the positive nutrient, in this case, calcium; in this case, potassium, ammonium, magnesium, and holds it so that it can be available to your plants and keeps it out of solution. Well, clay is actually the bigger component of negative charges in the soil, and it also has negative charges. So it's able to bind those cations to its surface and exchange them with other cations in the soil solution. That process is called cation exchange. And it's measured in the soil test by the cation exchange capacity. And it's basically the degree to which your soil can adsorb to the surface of the soil, adsorb, and exchange cations. And it's a measurement of the chemical activity of your soil. So this magnet, we all played with magnets in grade school, and some of us still do, but we all played with 'em in grade school, and we could see that we had unlike poles attracted and like poles repelled. Well, it's the exact same thing with the ions. So cation exchange capacity is, basically it's a measurement of how much clay or organic matter there is in your soil. And I would argue it's more the clay than it is the organic matter. I think more of our negative charges have come from clay than they do from organic matter. So it's almost a measure of texture. If you've got a very low CEC, that tells me that you have a very coarse textured soil, not much clay. So if you get to start to get down here in six to 10, which is what we would see in much of our soils in the state of Michigan, that means you're gettin' into that kind of a loamy texture, a sandy loam, almost a loam type texture. Then you get down into here, 10 plus, which would be our finer textured soils, much more clay. If you get up into soils that are above 20, we're basically talking about muck soils or organic soils, maybe black sands, but soils that have a lot of organic matter to get up that high. Next thing that we need, so that's cation exchange capacity. Very important, because it helps us hold nutrients in our soil. So pH is really another important characteristic of soil fertility, and it's basically just the measurement of the concentration of hydrogen ions in that soil solution and attached to the soil. So it's very important, but it's a measurement of the hydrogen ions in the soil. Why is it important? It affects two different things. It affects microbial activity and it also affects nutrient availability. So both are affected. And in soybean production, microbial activity is incredibly important to us because we have a symbiotic relationship with some bacteria that live on our roots, and they will actually fix nitrogen out of the air, out of the atmosphere, and make it available to the soybean plant. And the soybean plant in return, it provides nutrients to the bacteria living on the roots. So it's a really good relationship. So if we get low pH, we get our acidity, we get less microbial activity. And now, nutrient availability is affected also by pH. And typically, if you're thinking about, or the way I think about it, the nutrients that I work with, the more acidic the soil, the more excessive nutrients you're gonna have, the more toxic or excessive they're gonna be. And the higher the pH, the more likely you're gonna see deficiencies. It's not always the case, but that's kinda what I see with soybeans. This chart is really cool. It's a colored chart. I've never seen this. Usually it's black and white, but I like the colored version because it gives you two opportunities to see the availability of the nutrients. So what we have down here is the pH scale on the bottom and on the X axis, and then the width of the bar that we see for these nutrients shows you how relatively available it is. But this chart goes a little bit further, 'cause it also adds the colors. So you have the width of the bar, plus you have the color. So you're gonna have, the thickness is gonna be green. As it gets thinner, the bars are gonna get red. So red is tied up; green is available. Well, if we manage our soil pH right in this range here, they're saying 6.2 to 7.3, I really have typically seen 6.5 to seven, kind of a narrower margin. But regardless, if you look up through there, you're gonna see no red, and that the nutrients are very available for the most part if we manage our pH in that realm. And that's for mineral soil. It is a little bit different if you farm a muck soil, but this is for typical mineral soils. So what causes our soils to become acidic? That's because a lot of it is self-induced. Nitrogen fertilizer is number one. Ammonium sulfate is our number one culprit. It's the most, it's like four times more acidifying than any other fertilizer source. But that's the number one cause. Leaching of cations from rainfall is another one, a natural one that we can't control. Plant uptake and crop removal of cations is another one. We get some activity from microorganisms and roots, and then organic matter decomposition also contributes to it. But then acid rain is another one. So those are some reasons why our soils become acid. We can lower the pH, but that's not very common. The time that people really wanna lower pH is, I would say, home gardeners are the ones that wanna do this. Like, let's say for example, you wanna grow a couple blueberry bushes. Well, you might try to acidify the soil to be able to grow those blueberry bushes. Or if you wanna change the color on some of your blossoms and things like that on some of the ornamental plants, you might need to lower the soil pH. But typically, in a field crop setting or a normal gardening setting, it's not something we really have to do. It's not economical in a large scale. This is what we typically have to do. We have to raise the soil pH. We usually have acidic soils, and we have to raise the pH. And the way we do that is we apply lime, whether that's dolomitic lime or calcitic lime. The difference between those two is dolomitic lime has magnesium in addition to the calcium, whereas the calcitic lime only has calcium. And they're both beneficial. It just depends on what you need, what your soil needs. And your soil test will tell you that. So hydrated lime is just a faster product. It just breaks down faster. What really determines how fast your lime breaks down and neutralizes your soil is the particle size and the mesh size on it. Very fine particles will dissolve in a matter of months. Very coarser particles will dissolve in the course of years. So that's what really determines it. And the homeowner has several choices. You have pelletized lime, which is easy for you to spread in your spinner spreader and things like that. It's easy to use. It's like a granulated product. The problem with it is it really needs to come in contact with the soil to break down. It's really probably not as effective in a top dress application like that as powdered lime would be. Trouble with powdered lime is it doesn't go through the spinner spreader very well. You do need to use more of a drop spreader for that. But you can use either source. Wood ashes are an effective liming material, but you don't wanna go crazy with 'em. A quarter-inch layer is recommended at the max. But it is also a good source of potassium, which is an under-regulized nutrient in many of our soils. This is kind of an important thing. There's 16 essential nutrients. And an easy way to remember these is pretending that you're sitting at a restaurant and this is the place mat in front of you, and there's four lines on the place mat. It basically reads, that first line basically just reads Hopkins Cafe; second line is CB Manager; third line is Closed Monday Morning; and the fourth line is See You Soon. So that's an easy way to remember the 16 essential plant nutrients. Plant nutrients are broken into three broad categories. They're either macronutrients, secondary nutrients, or micronutrients. And what makes the difference is not the relative importance. It's how they're needed, the volume that they're needed in the crop. So macronutrients are needed in much larger quantities than micronutrients. Again, they're equally important. It's just the relative amount that's needed by the plants. So nitrogen is one of the big three. The three macronutrients are nitrogen, phosphorus and potassium. And nitrogen is really important because it promotes cell growth. It's really important for vegetative growth. And a matter of fact, if you put too much on, you're gonna get too much top growth, too much dark green leaves, and you won't get the flower and fruit set that you really want. And I think tomatoes is probably the easiest one to do that. You can get some really showy plants, but really reduced fruit set. Deficiency is shown by chlorosis or yellowing. Chlorosis is just a fancy word for leaf yellowing. It shows up in the older leaves. And the reason it shows up in the older leaves is it's a mobile nutrient in the plant. It moves from the older leaves to the newer growth where it's needed. Immobile nutrients, typically, the deficiency will show up on the newer growth, and that's because they do not have the capability of translocating through the plant as well from the older leaves to the newer leaves. But nitrogen is a mobile nutrient. The other thing about nitrogen is it can become a groundwater contaminant, and we do need to be careful in using it. So this is just a slide that shows this excessive nitrogen, just basically a jungle over here. And then here, we're seeing the deficiency. Nitrogen deficiency typically will show up as an overall yellowing, reduced growth, kind of an overall yellowing of the tissue. This is the nitrogen cycle. And the reason we show this is because we don't do a soil test for nitrogen, typically. And the reason we don't do that is because it is such a dynamic nutrient in the soil. It's always moving from one form to another. And so what form do you measure, is kinda the game that you'd have to be playing. So I just wanna talk about this, because I wanna show over here these four bolded terms. And because that's the way that nitrogen is lost from your soil. And, as a gardener, you're gonna wanna manage those losses. Otherwise, you think you've got your nitrogen needs fulfilled, when, in fact, you may not have them fulfilled. So we wanna prevent those losses. - [Christopher] Hey, Mike, sorry to interrupt you. We had a question in the chat. Someone was hoping, could you please repeat, you mentioned a place mat meaning? And then somebody- - [Mike] Yes, yes, let's go back to that. So let's say that there's 16 nutrients right here. So the way I remember that is, let's assume I'm sitting at a restaurant and this is my place mat that's sitting there. I've got my fork on the right. I've got my knife and my spoon there, and the place mat is sitting there, and I'm just looking down at it. And this place mat is from the Hopkins Cafe. So basically, what this tells you is that each one of those letters stands for a chemical element. So H stands for hydrogen, O stands for oxygen, P stands for phosphorus, K stands for potassium, and so on. So it's basically a listing of the essential elements that we need for plant production. And there's 16 of 'em. So it's just an easy way to remember it. Hopkins Cafe, CB Manager, Closed Monday Morning, See You Soon. So that's what it is. So it was each one of these is a different essential element. Does that answer the question? - [Christopher] I think so. - [Mike] Okay. - [Christopher] Thank you, Mike. - [Mike] No problem. So these are the four losses, ways that you can lose nitrogen. First one, let's look at denitrification over here. That happens when the nitrogen is in the nitrate form in the soil, and what happens is in a waterlogged condition, many of our bacteria and soil organisms have to have oxygen to survive. So due to their will to survive, they are gonna extract this oxygen atom from this molecule and use that to survive. When they do that, this nitrogen is free to combine with another nitrogen atom, and leave right up into the atmospheres as N2 gas. So that's denitrification. Under waterlogged conditions is when that occurs. Ammonia volatilization occurs when we apply any fertilizer that contains ammonia. And we apply that to the surface, and we don't incorporate it, and we don't water it in. If we get some hot summer days, it can volatilize as ammonia gas, and we apply it but we no longer have it. So that's volatilization. So the way to prevent that is to incorporate your fertilizers, it doesn't have to be deep, just an inch or two and, or water them in. So about 1/2 inch of water would be enough to water it in. And mobilization happens when, again, it's to this nitrate molecule. What happens there is our carbon to nitrogen ratio in the soil gets out of whack. And carbon is a really essential food source for microbes in the soil. So they have all the food they need, so their populations explode, but they need to have nitrogen to build their cells. And if there's not enough nitrogen around, they will pull it out of the soil. They'll pull it out of, take it and preferentially pull it away from your plants. So you'll see some nitrogen deficiency in your plants. You haven't lost it, technically. You've just lost it in that year's availability. It's tied up in these microbodies, and they will break down and release the nitrogen eventually. Probably the most common way that I've ever seen that is if you have a tree trunk where the stump has been ground, what you will see there is that sawdust. You'll have a yellow spot in your lawn almost forever. It just breaks down so slowly and it ties up the nitrogen so much that you just can't put enough fertilizer on there. So if you ever do grind a stump down, get rid of the sawdust. Get rid of the sawdust and that'll keep that from happening. Leaching is the last one, and that's the environmental one that's really negative. It happens only to this nitrate molecule, because it's got this negative charge. And remember what happens to negative charges? The soil has a negative charge, so it's repelled. It's not held to the soil. So it's free to leach out through the soil with any excessive rainfall or irrigation. So that's the ways that we lose our nitrogen in a garden setting. The next macronutrient I wanna talk about is phosphorus. Very, very important. It's associated with root growth, flowers. Gardeners, flower gardeners, really wanna pay attention to phosphorus and many other functions. We use it typically if we try to put some transplants in and we wanna get our roots to grow and make them adapt, we'll use some higher phosphorous fertilizers. And it is readily bound up and insoluble, and tied to soil minerals very tightly. It is a potential pollutant, not so much that it's toxic, but that it does degrade surface water bodies. And I'm an avid fisher, not fisherman, but swimmer, and I really don't want to have a lot of algae or seaweed in the bodies of water that I'm swimming in. So it is an important topic to me. But the good news is many of our soils do have plenty of phosphorus and we don't need it. So much so, because of these previous two issues, there was a law, I think, passed in 2012 in Michigan, where we really can't apply phosphorous fertilizers to our lawns unless the soil test specifically says we're deficient. So for our normal maintenance applications, a triple 12, a triple 19, a triple 10 is not an option for lawn, even in a commercial setting or homeowner settings. So that's something that we need to be aware of. We do see deficiencies from time to time, and it'll show up as purpling, typically, or reduced flowering. So here's the purpling that you will see, and it's very characteristic across plant species. Last one, macronutrient, is potassium. It's a commonly overlooked nutrient, but it's incredibly important. And the reason it's important is because it provides overall vigor and disease resistance to your plants, stress resistance. It helps them stand. And sometimes our soybean crop will lodge and be difficult to harvest. Lodging is just a fancy word for tipping over, laying down. And then it's hard to harvest. Well, one of the things we ask is, what's the potassium level in the soil? If it's not high enough, we will see that. And then improper fruit development will be another thing. It's not a pollutant, but it can be. It's very salty, so you have to be careful. If we apply it too close to the plant at too high rates or something, it can burn some things. Signs of a deficiency are reduced growth or vigor. We'll see marginal necrosis, or actually it starts with chlorosis. Necrosis is death, and chlorosis is yellowing, but it starts as yellowing, and then it'll turn to death around the margins of the leaves. You'll get wilt or poor fruit set. This is the yellowing that we'll see. And then you start to see the death around there, but it's always on the margins of the leaves. The center of the leaf will remain green. And that's true on the species that I've seen, grasses or broadleaves. Micronutrients, these are not any less important, but they're needed in such small quantities that we call them micronutrients. Zinc, manganese, copper, boron, chlorine, iron and molybdenum. Probably the most common ones that we would see are zinc and manganese in Michigan, would be the ones that would typically be deficient in a field crop setting or even in a landscape setting. Small amounts are required. The question is, do we really need to add them in? And I don't think in our mineral soils that we really do. If you're seeing deficiency symptoms to micronutrients, it's more likely the pH is out of whack. And I would say, if they're tied up, you probably have too high of a pH, is what's happening. So look at that situation if you do see the deficiency symptoms. This is just a slide that shows that the least nutrient is gonna be the one that limits ya. In this case, it's potassium, and that's gonna limit your yield. If one of 'em is limiting, it's gonna create a problem. We should have sufficiency levels of all of our nutrients. So now, so we've talked about the nutrients and let's talk about fertilizers now. This is how we get our nutrients. And first concept I wanna talk about is complete versus incomplete fertilizers. A complete fertilizer would have nitrogen, phosphorus and potassium in it, NPNK. An incomplete fertilizer is gonna have one or two of those, but not all three. A complete fertilizer might be lower in analysis of all three, or an incomplete fertilizer will have much higher analysis of that single nutrient. All of our fertilizers or commercial fertilizers are gonna have some inert material in addition to the actual nutrients. You're always gonna see three bags. If a product is sold as a fertilizer in the state of Michigan, it's gonna have three numbers on the bag. First number is gonna be the percent nitrogen by weight. The second number is gonna be the percent phosphate by weight. And the third number is gonna be the percent potash by weight. So if this is a 50-pound bag, we're gonna have three pounds of nitrogen, 12 pounds of phosphate, and 12 pounds of potash in this 50-pound bag. So that's the way to use those numbers. This is a really good fertilizer for Michigan because it's a lawn food and because it has zero phosphorus in there, the middle number being phosphate, so it has no phosphorus in it. This is legal to use in Michigan on all of our turf grass applications. We have organic fertilizers. They're typically lower in analysis. Look at how low those numbers are, but they are an organic form. Basically, it doesn't mean that they have carbon. It just means that they're derived organically, either from leftovers from the livestock industry or fishing industry or actual manures. So that would be our organic materials. Foliar fertilization is really not something that's really recommended for nitrogen, phosphorus and potassium because those nutrients are needed in such large quantities that you're just not going to get enough of them through the leaves. It's better to apply them to the soil and let the roots do their job of absorbing those nutrients, yep, adsorbing those nutrients. So you can use 'em for rescue treatments, but typically, we're just not needed in our mineral soils. Whether you're a gardener or whether you're a field crop producer, it's just really not needed in many of our mineral soils. There are some cases in field crops. Zinc and manganese are two that show up, that we do need zinc typically for corn; manganese more so for soybeans. There are some liquid sources. We use these in commercial agriculture, typically in band applications on our planting equipment, but we will also apply some of our nitrogen as a liquid source. But to the homeowner there's, a good example would be Miracle-Gro. Typically, they're complete fertilizers, but in some case, they are single nutrient fertilizers. But they're more expensive, but they're more convenient. And that's why we're movin' to those. So here's that definition of organic. A chemist definition would say that it contains carbon, and oops, I'm going the wrong direction, would say it contains carbon. To us as growers, we really just mean it's naturally-derived. And that's kind of the definition that we'll use. So this is kind of a neat slide. I apologize for the small print, but it is a good slide because it shows the three categories of fertilizers. We have conventional fertilizers, we have slow-release fertilizers, and then we have organic in these three columns. And then each column is divided in half by advantages being in the top and disadvantages in the bottom. And our conventional fertilizers have a lot of pluses. They're low cost, they're fast-acting. There's a lot of 'em out there, a lot of variety out there, and they're commonly available. They do have some downsides. Because they're so available, they can burn. So they can solidify. And if they're not used properly and be hard to put through the spreader, I've experienced that myself. You do have some high potential for leaching and denitrification of nitrogen, and they are acid-forming. On the opposite end, we've got the organics. They've got some benefits of having low burn potential, slow-release, they contain many nutrients. Some of 'em can improve soil structure. If they're the really bulky ones, like the manures or the compost, things like that, they can improve soil structure. But they have to be more of the bulky ones to do that. The downside is you're gonna have odor problems. You might have extra bulk and handling issues. They're gonna vary in their analysis so you're not gonna get consistency of your application. And then you will probably pick up weed seeds unless they've been composted effectively. This is that carbon to nitrogen ratio that I talked about. And the reason it's important is that for nitrogen management. You wanna avoid that immobilization, and you wanna shoot for a carbon to nitrogen ratio of 20:1. And if you've got that, that's just perfect. Where this can come into play is when we're adding compost or manure or green manures or cover crops, we can throw things out of whack a little bit. And I'll show you a chart. So here's some cover crops. Here's a Clover crop, has a 2:1 carbon to nitrogen ratio. Grass clippings have just about ideal, 12 to 25:1, and leaves are not bad. So, really, if you're gonna do some composting, they say an equal mix of grass clippings and leaves makes a really nice combination, and it'll get you close to that 20:1. Where I have seen this is in this sawdust. Like I say, where a stump has been ground down in a turf setting, you can't put enough nitrogen fertilizer on there to keep that spot yellow. That sawdust, just that carbon is just eatin' up all of the nitrogen. So that's where I've really seen it. I wanna talk about the rest of this session now on soil sampling and testing. And soil sampling is just incredibly important. It makes sure that our plants have what they need but not more than they need. And it just helps us know what to apply, and it helps us protect the environment. We can test for some extra things if you wanna do that. You can test for texture, particle size; how much sand, silt and clay is there in your soil. Or you can test for organic matter. That's kind of an extra test that you would have to pay for. It might be in the Homeowner Test, but I know for those of us in commercial agriculture would have to pay for the organic matter test in addition. Compost analysis is a separate test, you can have that done. Soluble salts, and then your irrigation water testing can all be done by our MSU Soil Testing Lab. When we soil sample, we want to focus on this down here. We want our soil sample to be representative. We want it to be actually representative of what's in that lawn setting or that garden setting or shrub root area. We want it to be representative. So keep that in mind. The way we accomplish that is we try to shoot for randomness and we try to shoot for many sub-samples, and typically 10 sub-samples. I'll go into a little bit more detail about that. But we wanna avoid odd spots, and areas around walkways and foundations. When we're taking our soil samples, we want to use a tool. And there's several choices up here on the left-hand side. This is my favorite, it's just the typical standard probe. This is a cutaway tube with a sharpened tip on it, and it just is really a handy tool. It's small enough to carry around very easily and takes a very uniform sample with each plug. I'm kind of biased towards this one. A garden trowel will work really well. It's a little bit thick there, usually an inch and 1/2 wide is what we would recommend for a garden trowel. This, again, is just a modified version of this, and then we could use a shovel. But so this shows how to do it. If you're using the probe, you just go down to the depth that you wanna achieve. If you're using a garden trowel, you dig a trench and then you shave off a slice off the edge of that. So various ways of getting the job done. We have a really good home soil test service offered by the University. And the lab has made this available as well as the Home Hort team. The smart team at MSU Extension is just really nice package. So what I'm gonna do is I'm just gonna jump right into this website, and sort of show you around it a little bit. It is really a handy website. Okay, so this talks about why we test and all the things that are available in a standard test. And yes, the Homeowner Test does include organic matter in the fee, so that is a nice, nice kit. But what you do is you obtain one of these Homeowner kits. So you purchase the kit, is the first step, and it's gonna cost 25 bucks. But in that 25 bucks, you get all of the analysis that was just covered there, but then you also get the free postage to send your soil test sample back to the lab; where those of us in commercial agriculture, we have to cover the shipping on it. We have a little bit smaller cost, we don't get organic matter for free, and we have to pay the shipping, which can add up when you're thinking about shipping soil. So that's that. How do you get started? Well, I think I mentioned you wanna purchase, well, the first step is to take your soil sample and then purchase the kit. But when you're taking your soil samples, in a homeowner setting, one of the biggest questions is, how deep do you sample? And in a turf setting, you only wanna go three inches deep because that's where the roots are. In a normal other-garden setting, anything else, for shrubs or a vegetable garden, flower garden, you probably wanna go six or seven inches deep when you're taking your sample. And you wanna sample, I would say, typically before you wanna put your fertilizer on, at least two weeks. It's gonna take 10 days for the results to get back. So I would sample probably two weeks anyways before I wanted to fertilize. And you want to get at least 10 random samples, and you wanna mix them up really thoroughly. A number of people make a mistake there and don't do a good mix. But you want that little one-cup sample to represent that whole garden area. And the best way to do that is randomized representative samples and then mix them all up. Let them dry a little bit, not with any heat on 'em, but just a fan, or just let 'em dry overnight on a newspaper or paper plate, whatever you wanna do. And then put 'em in the mailer and get 'em off in the mail. So that's how the Homeowner Tests would work, and it is a really slick system. So that's that. Let's go back to the top of the page and let's talk about your results now. So you've sent it in and now what happens? You will get your results back in about 10 days and you'll get an email. - [Christopher] Mike, I'm gonna stop you real quick. We're still seeing your PowerPoint slide here. Are you- - [Mike] Oh, you are. So you didn't see any of those other sites like this right here? - [Christopher] Yeah, could you just go back a few slides and just briefly go back over some of the, which ones you were talking about? - [Mike] Yeah, I sure can. Gosh, I'm sorry, because I'm supposed to be showing, I should have tested this with you, Chris, but I'm supposed to be showing the MSU Soil Testing site. That's not what you're seeing right now? - [Webinar Assistant] You may have to stop sharing and re-share, and select just the desktop or the browser window that you're looking at. - [Mike] Ah, boy, shoot. - [Christopher] We still have a decent amount of time. - [Mike] Well, this is gonna test my technical skills. I may need some help doin' that, because- - [Christopher] All right, so Mike, you're gonna go ahead and stop sharing. - [Mike] Stop sharing, okay. - [Christopher] Okay, and then you're gonna hit share screen again, but this time you're going to use, you're gonna select the window that you wanna share. - [Mike] Is that showing? - [Christopher] Here we go. Okay, was this the first website that you- - [Mike] Yeah, let me go back. Good, I'm glad you guys caught that, thank you, 'cause that was meaningless unless we're looking at this. Okay, so we're on the home site, yes. Basically what this is, is this is the MSU Home Soil Testing site. And it is just a really valuable resource. You wanna get to this site, and the URL will be listed in my presentation. But it just has so many tools here across the top that are so important to you. So getting started is one of the big ones. It talks about how to take a soil sample. It talks about how to submit that soil sample, and also how to buy the kit is on there. So it's really important. This is one of your main sites if you're a gardener. So then we'll go into the results. And so what you'll typically get is you'll get your results back from the lab. And what they'll send you as an email or a text with a code that you type into this site. You type it into here and it'll give you your actual results. It's really slick. Or another option is, let's say that you had your soil tested by a private lab and not MSU. Then what you could do is you could put in your crop, you can fill out all of this information here from your Soil Test Report, plug it into these cells, and then it'll generate a report for you. So I'm not gonna do that. I will show you an example of some other ones, though, where I have the codes. So the simplest way, though, is to just plug your code in. Another reason why you might wanna do this alternative method down here is, let's say, for example, you had a soil test run and you changed your crop. You wanna know, okay, this is no longer a flower garden, it's gonna be a vegetable garden. And I wanna use those same soil test numbers to generate a vegetable garden report instead of a flower garden report. It gives you the ability to just change the crop in there and do that. So it's pretty slick. But let's just go through and pretend that we're a grower that has a code. So these are just some samples. This would be a, I think it's a turf grass code. So we'll type that in. And it'll take us right to the report, our actual Soil Test Report, okay? So yes, this is run on a lawn setting. So they sampled three inches deep. And so here you have all of the nutrient levels that were measured in that soil test and the pH. So you can see those in parts per million. And you see the CEC that we talked about. This has got a pretty significant texture. It's probably a nice lone soil. - [Christopher] Mike, can you talk briefly about why people shouldn't be concerned about this very high part-per-million calcium? - [Mike] Why they should be? - [Christopher] Why they shouldn't be. - [Mike] Shouldn't be. Well, for one thing, it really doesn't have any negative problems. There's some people that think we need to balance our calcium and magnesium ratios, kind of a ratio balancing theory. That's a really old, old theory, and it's just not, the University doesn't subscribe to that. We feel that as long as you have sufficient magnesium and calcium, that you're good to go. The ratio is less important. So calcium just doesn't really have any detrimental effects that I know of. And in field crops, it never is limiting. And if it is limiting, all we have to do is apply lime. But the surplus, I don't think it ever has a problem, Chris, that I can think of. If it's short, it can lead to blossom in-crowd, I believe, in tomatoes. But again, if you're managing the pH properly in your soil, you should not have that problem. - [Christopher] Yeah, I just wanted to plug that, because that was a question I received at one point. It's more than 10 times the amount of phosphorus and potassium. So should they be concerned? Short answer, no. - [Mike] Nope, nope, I really wouldn't be concerned. And so that's the actual numerical values of what's found. And then over here we have just a graphical representation. You know, is it below optimum? Is it optimum? Is it above optimum? And that's only provided for the macronutrients or, I'm sorry, these three nutrients, phosphorus, potassium and magnesium. So that's what we've got. So we're scrolling down. So the first part is, what did we find in the soil? That's what the top part is gonna be. This is what the soil test measured. And we do need probably some lime. We've got some acidity here. We're at 5.8; six and 1/2 would probably be ideal. Organic matter's really good, though, 6.4%. This person's doin' a nice job. Probably mulching leaves back in or something to attain that. So we scroll on down, and then here's our actual recommendations. So this is what was found. This is what we need to apply. So our soil indicates that we need, on a per 1,000 square foot, we need to have three to four pounds of actual nitrogen and three pounds of potassium. If I first looked at this and I see what's in the garden stores, my first impulse is to apply a complete fertilizer, like a triple 10, a triple 13, a triple 19. But again, please refrain from that, because of that restriction we have, because of our Great Lakes and because of our inland lakes, we really wanna protect those surface bodies of water. And the way to do that is to not apply phosphorous when we don't need it. So avoid that impulse on turf. Don't buy it. Even though it's available in the stores, it's more for other garden applications than it is for turf. So kinda keep that in mind. So what you can do is, so it goes on down and it tells you some different options. You can use a winterizer type of fertilizer, something that's a little bit higher in potassium, so it's a little bit more balanced. Winter fertilizers typically just have a little bit higher potassium number than what a normal lawn fertilizer would have. So another option would be to apply the individual nutrients, like maybe some urea, just strictly nitrogen, and then some Muriate of Potash to get the potassium. So that's another option. Or you can use the common lawn fertilizers, like here. The troubles with those they don't have much potassium. So if you do this, if you go this route, you got lots of nitrogen, but you don't have much potassium. You're gonna have to come back with probably more potash. So everything else looks really good on that Soil Test. This is an important chart for turf, is that it shows you, it gives you your choice. Do you wanna have a low maintenance lawn, a medium maintenance lawn, or a high maintenance lawn? High maintenance means more fertility, more irrigation. Medium means very little irrigation but you still want a nice-looking competitive lawn. And then low is just basically just minimal management. So it's when you put the nitrogen on that makes a difference and how much you put on. And holidays is a good way to think about it. So May, this could be like a Memorial Day application, this could be a July 4th application, and this could be a Labor Day application would be a good way to kind of think of this one here. And the intense one is more. So you can see the Four Step, the Scotts Four Step program or something is more like this down here. And actually I think they even have an early application in April or something, which we don't recommend at the University. We just believe that promotes top growth and not root growth. So you'll be mowing a lot but you're not really building your turf. So that's just a turf recommendation. The other thing that's really nice about this site, and I don't know if you can see it or if our pictures are in the way, but on the right-hand side, right here, these Must Read Tip Sheets. These are really helpful. And some of them are not available at this site right here. I clicked on some of 'em as I was preparing, and they're not available there, the links are broken or something. But it's very easy, the best place to find all of the Tip Sheets is under Tools. So you go to this Tools area, you go to links, and then under there, there's just a lot of information, a lot of information on everything that you can think of. All the types of plants that you'd wanna grow, whether it be vegetables or turf or annual flowers, perennial flowers, shrubs, it's all there. - [Christopher] Mike, I just wanna give you a update on time. We have about nine minutes left. - [Mike] Okay. - [Christopher] So we can maybe get some questions in. - [Mike] That sounds good. I will just stop there. The only other thing I was going to do, Chris, is just maybe show one other example on the results. Let me do that, I guess, and then we'll start. - [Christopher] Yeah. - [Mike] So let's go back to your results and let's scroll down. It gives you a chance at the bottom of the page to put in another number. So I can't remember which is which. Oh, we'll just put one in and see what we come up with. It'll tell us at the top of the report. Okay, this is gonna be a perennial flower garden, which really don't need much fertility at all. The damage here is more likely of over-fertilizing perennials. So just be really careful when you're fertilizing your perennial flower garden. You wanna try to fertilize 'em when they're first emerging, and then maybe just leave 'em alone. No more than one pound of actual nitrogen per 100 square feet. And maybe it's 1,000 square feet. I think it's, nope, it's 100 per square feet for these. So again, same drill. This is what was found. And in the soil, the pH is really high. Look at that, calcium level's really high. Everything else looks pretty good. Organic matter is really good. And then they come down and they talk about what we need and various ways of applying it. So really helpful. There are some other tools that are available here. There's an area calculator that you can go to for calculating the area that you're trying to fertilize. And then there's also a fertilizer calculator. So there's some really nice tools at that site. I would become very familiar with that site if I was an avid gardener. All right, well, Chris, that's basically all I have. If I can try to answer any questions at this time. - [Christopher] Great, no, thank you. So we're gonna wrap up this session. But before we do, we get to questions real quick. If you need to head out, I'm gonna go ahead and put the evaluation link in the chat, okay? You're gonna select that link if you're trying to get RUP or CCA credits. And once you've done that, that's all you need to do for us to follow up with you to make sure that you get those credits. Let's go ahead and look at some of the questions that we had. The first one was, Mike, what's the difference between soil pH and buffer pH on a soil test? And what's that significance? - [Mike] Yeah, soil pH is extracted using just a 1:1 water solution, just distilled water and soil in a 1:1 ratio. And all that does is extract the hydrogen ions that are easily available, that are in the soil solution. So that tells you basically whether or not you need lime. That tells you what your actual pH is and if you need lime. What the buffer pH does is tells you how much lime to apply. And it measures residual acidity by plucking those hydrogen ions off of the soil, the organic matter, and the clay, the exchange sites, those negative-charged sites. And that's using a SMP buffer solution that extracts those. So that's the difference. One measures just your soil pH, so it tells you if you need lime or not. And then the second one, the buffer pH, tells you how much lime to apply. - [Christopher] And then we had a follow-up question on that. Regarding pH, where does one get wood ash as a pH raiser and potassium amendment? - [Mike] Oh, boy, that I do not know other than I've got a buddy that has a world's largest burn pile in his backyard. I mean this is a 20 by 20 circle, probably five feet high of wood ash. (laughs) And it's just phenomenal. And that's the only place I really know. I don't know that it's commercially available. I think it's more for like the homeowner that, you know- - [Christopher] Yeah. - [Mike] Has a fire pit. - [Christopher] I've heard that you don't wanna use ash from everything. I think walnut ash is one of those things you wanna avoid. But for the most part, yeah. If it's green and it burns, it could be wood ash. We have another question here regarding carbon to nitrogen ratio. So if sawdust can rob nutrients, so to speak, can fresh or not-so-fresh tree chips do the same? That was from Kate Tuttle. - [Mike] Yes, but I think it has to do more with the fineness of the material. The reasons- - [Christopher] You mean that surface area? - [Mike] Yes, the surface area. It's gonna break down so much faster in the soil. The microbes can have access to that carbon source. Think about the way the mechanism involved. It's the microbes that are feeding on the carbon source. They're multiplying like crazy, and they need to have nitrogen to build those new cells. So they're just not gonna be able to munch on those larger particles, those larger wood chips like they would the sawdust. - [Christopher] Yeah. And I'm just gonna answer a real quick question here from Lynn Stevens. If so many nutrients are bound by low pH, do you have to fertilize the daylights out of blueberries and azaleas? I actually happened to have worked with blueberries frequently. And as far as I'm aware, the recommended corrective action is actually to amend the pH instead. And, Mike, you can weigh in on that as well. - [Mike] Yeah, I guess I'm not sure about that, but in a commercial blueberry field, can you really, I just don't think you wanna raise the pH, because they need that acidity to- - [Christopher] Well, no, yeah, you wanna lower the pH. You wanna amend it- - [Mike] Lower the pH. I'm sorry, okay. - [Christopher] With like a pine bark chip is a really common one. - [Mike] Okay. - [Christopher] Yeah. - [Mike] Yeah, that I have no experience with, but that would be one of the rare instances when we're really trying to lower pH. Usually in most settings, we're trying to raise it. - [Christopher] Yeah. Florida is a big consumer of pine bark chips for their Southern Lowbush, sorry, their Southern Highbush varieties. Okay, we have one more question here from Kathy Krugel. I've seen ads for a liquid calcium/lime. Can you speak to the advantages or disadvantages of the liquid formulation versus the powder? - [Mike] It would be very easy to apply. I'm not familiar with the product, I'm sorry, but I think ease of application would be one, and then rapidity, the availability of what it's gonna correct the problem. So those would be the two that I would think. But if you're using powdered lime, it is truly the powdered lime and not the pell lime, you're gonna get very fast results from the powdered lime. 'Cause a very high percentage of that or certain percentage of it is in a very available form. - [Christopher] Excellent, okay. And I think that might be all the time that we have left. I just wanna everybody again for participating today. If you are a master gardener and you're seeking to use this as educational credits, please make a note in your personal records so when VMS opens up again for continuing education hours, you can log that in, you can log the full amount of time starting at 1/2 an hour. If you attended the whole session, you can log up to an hour. Thank you so much, and please join me in thanking Mike for his fantastic presentation. - [Mike] Thank you, thanks for having me.

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