Cut Input Costs with Cover Crops and Biology

0:00 Yeah yeah you live in parts of Kansas. Right, yeah, didn't believe it. It's like wow, who just torches a wheat field like that? We starve is the grain, then torture, just insulting.

0:23 It's 5:30 so we're gonna get. Hey, why don't you go ahead and start sharing your screen? I'll kind of go over the rules again. I know this is kind of monotonous—we go over them every week, but for those who are attending and this is your first time: you are all on mute. And if you have questions throughout the webinar, feel free to ask those either in the Q&A portion or in the chat bar on the side.

0:46 And then we're gonna let Dale go again here. This is gonna be similar to our perennial pastures webinar that we did two weeks ago. If you've missed any webinars and would like to watch those, they are on our YouTube page, or you can go to our website and just search webinars and they are all listed there. He did an excellent webinar on establishing and diversifying perennial pastures two weeks ago that you can go see. This is gonna be a similar format—we're gonna let him go for about 45 minutes and then open it up to your guys's questions. As you are listening and paying attention, if you've got questions, feel free to either type them up or hold them to the end.

1:27 So with that, I'm gonna let Dale go. He has been an agronomist and sales rep for us at Green Cover Seed for the last four—did we decide if it's four or five years, Dale? I believe it's four. Okay, we're going with four. We just seems like five. Dale, everybody else, we're very blessed to have him on our team—just the amount of wealth of knowledge that he brings and wants to share with you guys. So with that, Dale, why don't you go ahead and talk about why biology is so important for cutting your input costs?

2:01 Well, okay, well I guess I'll start with a dream that I know a lot of us share, and that is someday passing our farms on down to our children and their grandchildren, so that our farms will be a source of wealth and prosperity and happiness for generations to come within our family. And sadly, there are some forces at work that are interfering with that. And obviously we're faced with some very low prices, and has put some people in some bad situations.

2:44 Now we don't have a lot of control over what commodity prices are. Some of us are selling direct, and that's been helpful. And we don't have a lot of power over what the prices of our input costs are, but we do have a lot of control. This powerlessness has led to a lot of depression, hopelessness, and in some cases has become very serious. And so I think if we can—a lot of the depression, the hopelessness is obviously financial stress, you know, the almighty dollar. But it's not so much that the dollars as it is the feeling of hopelessness and powerlessness because we can't control the price of what we sell, we can't control the price of what we're buying. But what we can control is how much of those inputs we have to buy.

3:50 Is there a way of farming in a manner where we spend less money on inputs and still maintain the same or similar yield levels? So let's take a look at some things that maybe we can do. I think one of the—showing a picture here of a nitrogen-deficient corn plant. And if you look at, do an enterprise analysis of your growing corn—obviously nitrogen fertilizer is a very big expense. Are there ways we can make around it? Well, I mean everybody's aware that you can provide nitrogen with legumes. We know that for roughly 2,000 years Roman authors talked about rotating with legume crops and their observations on that before they understood what was going on. Because nitrogen fertilizer became so cheap after World War Two, we altered our crop rotations and our cropping patterns where we really don't fully utilize legumes as a nitrogen source like we used to. And so can we utilize legumes?

5:14 More effectively to reduce our nitrogen fertilizer costs. I think the first thing we need to discuss is just how much nitrogen can you expect from a legume cover crop? What's realistic and what are some possibilities? Well, first thing, how much nitrogen do you get from a legume cover crop? Your legume is entirely dependent on biomass. Legume, most of the nitrogen that a legume crop is going to fix is going to be in the biomass of the legume. Some of it will be out in the root exudates, but most of it, almost all of it in an annual legume, will be in biomass in the plant in the form of protein, and they're about 18, 19 percent protein on a dry matter basis. And because protein is 1/6 nitrogen, that equates to about 3 percent nitrogen on legume biomass. So if you have, let's just say, 3 tons per acre of legume biomass out there in the form of a cover crop, that's going to have about 6,000 pounds times 3 percent, 180 pounds of nitrogen. You think, wow, that's quite a little bit. That's as much as I put on a dryland corn crop. I've got it made. Well, but here's a caveat with that. When that nitrogen and when that legume biomass is degraded, first of all, when you kill it, it's not immediately available to your next crop. That's both good and bad as we'll discuss later. But microbes have to work that over, chew it up, spit it out, and microbes are going to retain about half of that nitrogen within the first growing season. Half of it will be available to your crop. So of that, in our example, three tonnes of legume biomass per acre, 180 pounds total, about half of that is going to be available to our crop, or 90 pounds. Well, that's helpful. That's good. But it may not meet our complete needs of our crop.

7:42 Now, that doesn't mean necessarily that this is not going to be very, very useful, because what happens to the remaining nitrogen? What about the half that's not available? And it's still there. It didn't go away. It didn't disappear. About half of that half will be available in year two, and half of the remainder. So, you know, this year you get a half, next year you get a quarter, the following year you get an eighth, following year you get a 16th. If you do this cover cropping thing every year, then you start adding quarters and halves and eighths and a quarter from the previous year and an eighth from two years ago and a 16th from three years. You can see you start stacking, you start building this pool of available nitrogen in carbon-based forms every year. And the longer you're in this, the bigger that pool is going to become and the less dependent on fertilizer nitrogen you're going to become. So this is something that gets better and better every time you do it. But the first year out, have realistic expectations of how much nitrogen you can get. And you can go out there and measure the biomass and get a pretty good estimate of about how much is going to be available. If you figure that that legume biomass is about 3 percent nitrogen, and if your next crop is corn, a corn crop whole plant, this is going to be maybe somewhere around one to one-and-a-half percent nitrogen, it's pretty easy to realize that it takes about three pounds of each pound of legume biomass is going to be enough to grow about one pound of corn biomass. When you figure the half availability and the rest of the nitrogen might have to be supplemented in another form, but it's still a significant contribution.

9:50 And so what are some crops that we can use to grow some nitrogen and how do we fit them into their rotation? Well, this is crimson clover. It's one of our winter annuals. So the winter annual legumes be things like crimson clover, balanza clover, hairy vetch, some of the a little less winter hardy ones like common batch or spring peas. Winter peas can all fit into crop rotations in other ways, but these are ones that can be grown in between row crops. You know, these are.

10:30 Ones that can occupy the ground during the winter because growing conditions are not as conducive to plant growth in the winter obviously as they are in the summer. The nitrogen fixation per day of growth is not as great but the window is usually very long and you're not taking out of summer row crops if you're in a summer row crop area like most of the Midwest is. People are very unwilling to give up that summer period in order to grow nitrogen, so that's where winter cover crops can come in.

11:07 The value you get out of a winter cover crop depends mostly on how long you let it grow in the spring. April first you're going to have maybe 20% of your nitrogen fixation potential achieved with a winter cover crop. So if you're killing it early and planting corn like most people want to plant corn in April, it seems like you're not going to get a huge amount of benefit from a legume cover crop as far as nitrogen. Now there's other benefits obviously, but the nitrogen fixation value—probably 80% of that on a winter legume is going to occur between the first of April and the first to June. If you are willing to delay the planting of your next crop into late May early June, you can really generate a substantial amount of nitrogen from these winter annual legumes.

12:11 You're planting early, maybe not so much. Another window that I think we fail to use, especially in the Corn Belt, is where having a cereal grain in the rotation can be very very beneficial, and that's using some of the summer annual legumes. This is sun hemp. This particular sun hemp crop was planted double crop after wheat harvest. This was in the Kansas or Kansas River Valley, should be northwest of Topeka. This particular field had never raised a corn crop to maturity because it was just sugar sand, no organic matter, no clay, and the water holding capacity whatsoever. But look at the biomass and the nitrogen that's contained in this crop. I mean, this is pretty impressive.

13:00 Legume, but you can do even better than this. Remember what we're doing with biology is we're harnessing the things we get for free—sunlight, carbon dioxide, rainfall. We're harnessing those to produce biological energy from photosynthesis to feed microbes that work for us. We're feeding our workers with free inputs, so it's all about capturing sunlight and converting it into, in this case, nitrogen. So one way of doing that better is like what I have shown here: this is a cow pea plant that is vining up a sun hemp plant.

13:52 Now the sun hemp picture I showed you earlier, you noticed the sun hemp plants are very vertical. A lot of sunlight can go down between the plants and hit the soil and get wasted. We don't want that sunlight wasted. We want every little photon that hits that field we want captured and put to use photosynthesizing so these plants can send energy to the bacteria on the roots that make nitrogen. When you combine the sun hemp and the cow peas together, the cow peas will bind up those plants, spread leaf area. You can fit three acres of leaves in one acre of land by having that big corrugated canopy and capture every little bit of sunlight out there and put it to work making nitrogen. And so that can give you just a lot more efficient canopy.

14:51 Now another means of fixing biological nitrogen is not with legumes—although that's what a lot of people are aware of. Legumes, but another source of nitrogen that a lot of people are not aware of are free-living nitrogen fixing bacteria. The first soil bacteria ever actually scientifically recognized and given a Latin name was called Azotobacter, after the person who discovered it, and Azotobacter is a free living nitrogen fixing microbe. The organism, the Clostridium bacteria like the ones that cause tetanus and overeating disease and sheep blackleg.

15:38 And cattle, those are nitrogen fixing bacteria. We have pretty well ignored the potential of these organisms in this country because fertilizer has been cheap and readily abundant for a long period of time, although given our current prices, you know, it's arguable whether fertilizer is actually still cheap.

16:08 So what's the potential of these free-living nitrogen fixing bacteria? These are bacteria that can fix nitrogen really in the rhizosphere of just about any plant, and the more sugar that plant produces, the more they're capable of fixing. So high sugar exudate type plants like corn and particularly sorghum, these microbes can go down. I'll show you some data from some foreign research. This from Brazil on corn, you can see where the nitrogen fertilizer rate was 0 pounds per acre and the inoculant showed a 14 bushel response. And then you put on 91 pounds of nitrogen an acre and really didn't make any difference whether you inoculated or not at that rate, but you can see that the inoculation yielded pretty close to what 91 pounds of nitrogen did.

17:16 Now does that mean that this replaces 91 pounds of nitrogen? Probably not. You can see that the inoculated at 0 pounds was still pretty good. I mean on 0 pounds of nitrogen, that's a pretty good yield, so there's probably a lot of soil nitrogen in this field anyway.

17:36 I'll show you another trial. This is probably a little closer to realistic expectations of what to expect. You can see with no nitrogen fertilizer applied, and this was an average of 6 trials, 6 locations in India, 12 bushel response to inoculate with a source bacterium. You can see at 36 pounds of nitrogen per acre, there's still a benefit to inoculation, but it's not as big. You get your best benefit from these where you're not nitrogen fertilizing, and you can see that while inoculation didn't quite produce as well as 36 pounds of nitrogen.

18:20 So how much nitrogen do you get out of these free-living nitrogen bacteria? It's hard to say, but in this case it looks like maybe you're in the thirty pound range that would be reasonable to expect. That's not enough in a corn soybean rotation to maximize corn yield. It's not enough in most US cropping systems to maximize yield by itself. And so that's one reason that these inoculants have never really caught on. They're mainly used in less developed countries that don't have easy access to fertilizer and have small land areas where they can't really justify the equipment for anhydrous ammonia or other fertilizers. But this is something you can walk six miles to town and carry it in your pocket, an inoculation treat your whole ten acres.

19:30 So it has never really caught on in the US, but does that mean that we can't use these? I think there's tremendous potential for these organisms actually. Let me show you, take a look at this field. I mean, this is a mixture of both grasses and legumes and broad leaves. You know, we've got some sorghum and some millet out here along with some sunflower, with some cow peas and a mixed species cover crop. I mean, this is mostly what we deal with. That green cover seed is mixtures like this. What if now you're not going to put nitrogen fertilizer out here because if you do, all those legumes won't nodulate and they won't produce free nitrogen for you? That's one of the reasons we put this out here is to get capitalized on the legumes and the free nitrogen they produce. But if you don't put nitrogen out there, the grasses are not going to live up to their potential.

20:38 So what if you treated this with an inoculant containing free-living nitrogen fixing bacteria, so not just the legumes produced nitrogen but also the

20:49 Sorghum in the millet, how much benefit does that give you? An extra 20 pounds of nitrogen that's enough to produce one ton per acre of additional green sorghum forage. And that nitrogen doesn't go away when you pasture this—it comes back as manure and urine and it's still in the soil to benefit the following crop and the rotation.

21:14 I think in these mixed grass legume situations where we're not applying external nitrogen fertilizer, these free-living nitrogen fixers can be really beneficial. And this is mostly what we do at Green Cover Seed—mixtures like this, whether they're annual or perennial, mainly for pasture with a high percentage of legumes. This is where these free-living nitrogen fixers have a real fit in my mind.

21:48 Now one question I've been getting a lot—I think I started keeping track, I had three calls on this yesterday, one today—someone wanted to know: what can I plant with my corn so I don't have to put fertilizer on my corn? And I hate to burst people's bubbles, but you will get very limited nitrogen benefit from a companion legume in this year's corn crop.

22:23 Now what I have here is a picture of cow peas as a companion crop to corn. And most of the nitrogen that those cow peas make is in that cow pea biomass. Only a very small portion of the nitrogen those cow peas made was leaked out in the root exudates where the corn can pick it up. Now you can often see when you plant companion legumes in an unfertilized situation, a lot of times you'll see a green-up of those corn plants where the roots are in and connected with the cow pea, but it's almost never enough to what I would say produces an economically viable corn crop.

23:13 Does that mean that we discount this? Absolutely not. I think there's a lot of value to this companion cropping deal, but you have to realize the limitations.

23:35 Now, how can you capitalize on this system here? I think one way is let's have a legume cover crop growing prior. Let's have some nitrogen in the form of protein prior to growing the corn out there. I think that's important. Let's do our winter cover crop or maybe a summer annual cover crop the summer before, maybe both. The next thing is, when we plant the companion, if we want to maximize the nitrogen transfer over to the corn—if that's one of your goals—I think it's important that we inoculate with mycorrhizal fungi.

24:17 And this picture shows the little yellow things sticking out—the little peninsulas or fingers that are yellow there—those are roots from two adjacent plants. And the mycorrhizal fungi are the white filaments, the threads. And you'll see that those white threads are connecting the roots of those two plants.

24:39 Now I've seen a little video clip at a conference on mycorrhizal fungi where they used motion picture x-ray film. And they had an alfalfa and brome grass plant side-by-side, and they're showing a picture, the film of the roots—these were growing in a growth chamber—and they put radioactive labeled nitrogen in the air above both plants. And the radioactive labeled nitrogen went into the soil, was fixed into plant-available forms by the nodules on the alfalfa. And within about 45 seconds you could see the little glow in the mycorrhizal fungi hypha move from the alfalfa to the grass—45 seconds—and it was over there.

25:28 Ordinarily I was taught in college that for a legume to benefit another plant next to it, it had to first die and decay. And for the most part, if you are in a system lacking mycorrhizal fungi, that's largely true, but there will be some leakage of root exudates from that, but most of the time that's fairly limited. But with mycorrhizal colonization of both plants bridging them together, you can get an almost immediate transfer. Now again, most of the nitrogen will still be in the legume plant, but the mycorrhizal fungi

26:08 Connection will greatly facilitate sharing of resources. So if you want to really take advantage of companion cropping, I would try to make sure you have microphones up there. Now the other thing you can do is inoculate with free-living nitrogen fixers. I think that's a situation where you're trying to minimize your amount of purchased nitrogen fertility, try to capitalize on as many of these. Like the Chinese say, you know, if you want to break a wall, instead of one big hammer, you use many small hammers. We're using many small hammers here to try to reduce our nitrogen fertilizer needs.

26:53 Now another thing that people are interested in is, I think most people are aware that you can biologically make nitrogen and that's been known by most people in annular culture for a long time. But they say, well, yeah, you can make your nitrogen, but you got to buy your P and K. Is that true? In most cases, it is true. However, let me show you some things. Most of the nitrogen that we apply as fertilizer is water-soluble ortho phosphate or Holly phosphate. And when we apply that to the soil, very quickly there are chemical reactions that start taking place that reduce the availability of that phosphorus. Phosphorus in water-soluble form is tied up by calcium, it's tied up by iron, it's tied up by aluminum, it's tied up by manganese. These reactions take place very quickly. And so because phosphorus does not move in the soil, we can't really top dress it, put it on after the fact. We try to put it all on pre-plan. That means what we put on has to remain available for the entire season. So when we realize that 85% is going to get tied up and we need to make sure that we have enough available to last, that means we traditionally apply seven times more phosphorus than what we need to get in the plant to make sure it's available throughout the entire season.

28:40 So what do we do different? Well, one thing we can do is we can add things to that phosphorus fertilizer that keep it available longer. And I've got a couple things here on the picture. One is humic acid, and I've got a picture of halo, which is the form of humic acid that we sell in association with our partnership with elevate egg. And humic acid will complex with the phosphate ions. And that complex is still available for plant uptake, but it's not subject to fixation, or not as subject to fixation. That complex will remain available to plants much, much longer than the phosphate without the humic acid.

29:27 Another additive I've got is the Brer Rabbit molasses there—any sort of energy source. And molasses has high levels of soluble sugars. It is, when you apply molasses to the soil, you get a frenzy of microbial activity as you've got this really easily available food source. So when you add molasses to that phosphate fertilizer, it's readily, quickly taken up and incorporated in microbial bodies, microbial compounds that are no longer water-soluble. They're not subject to being tied up like water-soluble phosphorus is. There are now slow-release, slowly trickled out organic compounds that break down and release small amounts of phosphorus throughout the season.

30:22 So by combining these compounds or these products together with phosphorus fertilizer, the theory is that we can apply less. Now I haven't seen the research to know exactly how much less, but the theory itself is very sound. It's very interesting. And if any of you listening have some experience with this, I sure appreciate you chipping in and giving us your experience.

30:57 And then what about the phosphorus potassium that's in our soil? Let's just talk about phosphorus. You know, I live in an area where we're told our soils are deficient in phosphorus. Therefore, we need to fertilize. Well, if

31:09 You look at the analysis of shale and limestone. If you talk to a geologist, get an analysis of all the chemical elements that are in those rocks. Shale and limestone are oceanic sediments, sedimentary rocks, a little less than half a percent phosphorus. If that's not very good, well let's do some math here. If you look in the top three feet of the root zone, now if every six inches weighs two million pounds, three feet weighs 12 million pounds. If you do the math, 12 million pounds times 0.0045, we have 54 thousand pounds of phosphate an acre pooled in our soil. That you take a soil, ten traditional soil test it might tell you we got dirty.

32:07 What's the difference? Well obviously, the soil test is an extraction that's supposed to tell us how much is available to plants, and the geologist's test, which is what we're looking at here, tells us how much total ore is. That's an insanely huge discrepancy between available and total. Why is there that big of a difference? Well, one is that the vast majority of this fifty four thousand pounds phosphate is locked up inside rock particles. Now does that mean it's never available? If it was never available, there would never be plants growing anywhere on earth, right? I mean think about it. All this had to become plant available at some point in time somewhere down the line. There are forces of nature that render these unavailable sources of phosphorus into available, or we would not have soil, we would not have plants. Now there would be no life on earth.

33:15 So I was planning a crop of rye once and it was late summer, just unbearably hot, and the surface of the drill was so hot I couldn't even touch it. And so to load up the drill, I backed up into a woodland next to my house by the field and let it cool down for a little bit, and then I'd fill the drill and go out and plant in the field. Now out in the field, I applied a hundred and twenty pounds of nitrogen, I put on 50 pounds of phosphorous and ten pounds of sulfur and a pound of zinc and a third of a pound of copper. I mean, everything that I thought this plant could possibly use fertility wise. He's filling the drill up in the woodland, I spilled some seed. The next spring, rye in my field was about middle of my chest high. The rye in the woodland, which has never ever ever been fertilized in history, was well over seven feet tall. Now I don't know what's in my woodland that is not out in my cropland. Whatever it is, I want it in my cropland. Well what is it? I suspect it's biology. It's biology. All this biology is fed by, well let me back up a little bit here.

34:49 What kind of biology is out there? What am I missing? This is a picture of a pine root or a pine seedling and say wow, look at the size of that root system. What you're looking at there is really not root system, at least not mostly. I just drew an outline here—the little red line—that's the size of the pine root. Everything else you see there is mycorrhizal fungi. And so most of the look at the surface area of that, the amount of soil explored by that mycorrhizal fungus, far greater than what the root by itself does. So for an immobile nutrient loss, first mycorrhizae fungi can just be absolutely huge, and most of our cropland is really very deficient mycorrhizal fungi. We had all of our fertilization practices are based on the assumption that we do not have mycorrhizae present, and it's not so much just the mycorrhizae. This is a microscope view of mycorrhizal fungi, and you see all those little articles that are all over these—you know, looks like strands of spaghetti. All those little specks on there look like cookie crumbs on spaghetti, or parmesan on spaghetti I should say. All those little chunks of parmesan on there are bacteria, and there's bacteria. Many of those bacteria are capable of extracting minerals out.

41:40 Come out and people say oh there you go. If you bury those pig weeds they're not going to come up. That's true, but what will come up is the pigweeds you buried last year. Now show you how this works because the deeper you bury, if you look at this, all these pig weed seeds start out a hundred percent viable. And you can see like the yellow line where you buried it. The deeper you bury those pig weeds, the longer they remain viable. If you let pigweed see just simply, or any weed seed, remain on the soil surface, it'll have a very high mortality rate. In fact, one year of laying on the soil surface will kill 90% of pig weed seeds. All kinds of animals eat them, the loose germ, there they mold, there's all kinds of hazards that can happen. When you bury them they will live longer, so leave them on the surface. They're easier to deal with there.

42:40 And the other reason is when you do that burial operation, most especially if this is pre-plant tillage, many weed seeds need a microsecond burst of light. In northern Germany, look at this where they tilled, now this was in a greenhouse where they tilled during light, 98% germination on pig weeds. Where they did the same process but in the absence of light, only 14% come up. Tillage stimulates weed germination. Now how could be used that little bit of knowledge I shared with you about the depth of burial to control these weeds? Maybe instead of using tillage to bury it, what about growing a cover crop to bury it? I mean, pig weed seeds only have enough energy to grow about three quarters of an inch before they run out of juice and they have to have hit sunlight. By the time that seedling along eighths to three-quarters of an inch, it has to hit sunlight. Where it dies, it will starve.

43:59 Now corn is a very big seed. It can come up from a substantial depth, whether that's depth of soil or depth of mulch. If we leave the pig weed seeds on the soil surface but creating mulch that's more than three quarters of an inch thick, and there's those weeds, are mostly going to starve out before they hit some light. And you can see the Reimold sheer kilograms per per square meter over here at the far right. That's about 3/4 of a ton per acre of rye mulch. But that's not a lot. And we'll revisit the red mulch later. Another means by which you can use cover crops for weed control as a lella pathy, and the plant I've got here, this is Mexican bottlebrush plant. And it contains chemical compounds that inhibit the growth of other plants.

44:54 Why is this important? Excuse me. The scientific name of the Mexican bottlebrush plant is Calisto. Sound familiar? That's the plant from which they derive the original compound they synthetically produced. Now that's a synthetic analog of the compound found in the Calista moanin plant. Is this an effective herbicide? I think, have you used it, you'd say yeah. See the little pink flower next to the Callisto name? That's where it comes from, Mexican bottlebrush plant. So yes, plant compounds can be very effective for weed control.

45:38 And one of the plants that produce some very strong natural herbicides, dry ripe, reduces some benzoic acid. The name of one of them is called dim boa, which is an acronym for a very long chemical compound that I won't even try to pronounce. But rye produces three of these benzoic acid compounds that are very suppressive of, among other weeds, mares tail and pigweeds, two of our worst weeds. Now so rye can be used very effectively. There's another mechanism at work with some of these. See how this works? You can see the line right down the middle of the field. To the left where you're a cover crop and to the right there was no cover crop. And you see the abundance of weeds where there is no cover crop. Why is this? Well, could it be the allelopathy? Could it be the?

46:37 Blocking of the light. What happened here and it could be both of those but there's another mechanism at work as well. You see how well the soybeans are growing? What can soybeans do for themselves that most weeds can't? It's fixed nitrogen. When you use the winter cover crop to suck up all the available nitrogen and sequester and hold it in the mulch, these weeds have no nitrogen to grow with. Soybeans don't care, they make their own.

47:10 So by using cover crops to manage nitrogen availability, the temporarily sequestered now—that nitrogen didn't disappear, it's still there, it's in the residue. It'll rot and it can feed next year's crop. This is building up your big pool of organic nitrogen, remember? So you tie that nitrogen up temporarily. You give your legume cover crop or you give your legume cash crop soybeans a fighting chance and they now have the competitive advantage over weeds.

47:43 Now you say well that—and it, this rye thing before soybeans—is very effective pigweed control. You can see you look at that two months after planting, deal about ninety percent control of pigweeds, my number. Now what they don't have in this data is the biomass of the pigweeds because in my experience the pigweeds that do come up in a rye cover crop are so starved for nitrogen they really have difficulty growing.

48:19 So you know, we're going about another two more minutes and we're going to have to open it up to questions. Another means—and this is just a sorghum cover crop that has been frost killed and then a crop of peas planted in here—and you can see the same pea crop at harvest, same concept now.

48:41 You say my next crop needs nitrogen—like my next crop is corn. I can't use this, I can't tie up nitrogen in corn. Let me show you this: a hairy vetch cover crop being roller crimped down and corn planted directly into it. Perfect weed control. This is no-till, organic, no tillage, no herbicides, no weeds. How does this work? Well, obviously the nitrogen in that batch is not available to the weeds nor is it really available to the corn until it breaks down. But what you can do as a manager is put nitrogen right down that row, whatever form you care—and pure organic like in this situation, fish hydrolysate or blood meal, some high nitrogen organic source, or just if you're not organic, just starter fertilizer—to keep that corn plant vigorous. And then you can see a little later, still no weeds, healthy green corn, a pretty good system.

49:46 And this is a situation using a living cover crop. Spray out a band with the planter, then come back in about this stage with a mowing device, cuts off all this clover, blows it at the base of the corn plants as mulch to both control weeds and feed the next row.

50:16 Now I am going to wrap—get down to—well, wanted to mention a couple books for sale and asking $30 for Managing Pasture, $25 for the Drought Resilience Farm, and also here, Soil Health Resource Guide. Those are completely free. We would be happy to send you on either electronic or the paper copy if you prefer, and visit our website at greencoverseed.com.

50:55 Yeah, and with that the resource guide, you can request a free copy of that on our website if you just go to greencoverseed.com. You can get that and we'll cover the shipping cost to ship that to you. Also, Dale's books are excellent, well worth the $30 in education and savings alone. I can't tell you how many people have heard talk about how much they have even saved on their farm by reading those books, so well worth the $30. Thank you, Dale.

51:29 There's a lifetime supply of Sominex. Yep, we're going to get it going on some questions here real quick. There was actually quite a few in the chat as well as in the QA on how you actually apply mycorrhizae fungi, molasses, and similar products. Do you have an…

51:49 The answer for that, the mycorrhizal fungi can be the easiest ways, just apply it to the seed. The spores are very durable, they can handle all kinds. They can handle some light freezing, drying. They're really pretty tough as long as the hyphae are fine. As long as they have a living root as a host, so you apply the spores where they're going to contact a root. The root tip of the root has a hormone, an exudate called strigolactone that stimulates the spores to germinate. So as long as the spores are put where the root can intercept it, it can take off and go. And you really only need about one spore per square foot in order to get good colonization. The inoculation at a full rate costs about twelve dollars an acre. That'll give you two spores per square foot. They got one to two, one to use in one spare.

52:53 As far as the molasses and the humic acid, that's obviously easiest if you're using a liquid phosphate fertilizer. You can also mix it with twenty-eight percent nitrogen. It has a number of the same benefits in turning a water-soluble fertilizer into a stable slow-release fertilizer through microbes. And it's not as easy if you're using dry fertilizer. Obviously that's going to take a little more creativity, but I know people that are doing it using some sort of device to place dry fertilizer and then injecting a liquid that contains molasses and humic acid right in the same zone. That's a mechanical issue, not an agronomic one.

53:49 From Kent: Will rotational grazing of a cover crop significantly reduce the amount of nitrogen available to the following cash crop? Yes and no. Grazing, you are going to lose some nitrogen during the grazing process. About seventy-five percent of what the animal ingests will come back out as manure and urine. The issue is 75% is still there. Some goes in the animal, some is lost through volatilization. The bigger issue is distribution. And if you are continuous grazing, just give them the entire field, you'll see a migration of nitrogen towards the water source and shade. Wherever they go to lay down will end up being where all the fertility ends up. When you're rotational grazing, you have more uniform distribution of that manure and urine. It's much better. Now the problem with that is you're taking however many square feet an animal grazes in a day to meet its needs, and the defecation and urine spots that it will produce is about 25 square feet. So you're taking all the fertility from a large area and depositing on 25 one-foot squares during the course of that day. So the distribution of that may be in hot spots surrounded by relatively impoverished areas.

55:35 I would not count on a grazed crop to meet a lot of your fertility needs on the next year. What it does do is, again, be in this for the long haul. The grazing of the crop is where you make your cash flow. Use all that manure and urine build-up as your long-term fertility reserve. That's where you're building up your pool of organic nitrogen, phosphorus compounds. Use it as a soil health program, not so much a fertilizer program. I would not back off on your fertility program initially, and be on the conservative side. I would say this stuff all works, but it all takes time. Build that system up. Don't shortchange your crop and be disappointed and then just quit. That's the worst thing you can do. Be on the conservative end and don't sacrifice a crop on principle.

56:48 Fernando said, 'Deal, could you please write the name of these cover crops fixing nitrogen here in Sonora? A few used Cespaedia in fixing legumes?' Yeah, so if you want to kind of, I wouldn't say you talk about every single list, but you can name that. There's really too many to list.

57:14 I would best advice I can give is to go to our website and watch our YouTube videos on the individual species. Now obviously the conditions that we have in Nebraska and Texas are going to be different than in Sonora, but a lot of the products that work at our summers do work in Sonora as well. Our winters are going to be drastically different, obviously, but the only way you find these things out is by doing some experimentation, do some planning, evaluate things. Don't look for a recipe. Try to learn as much as you can about the individual plants and again go to our website, look at the YouTube videos, learn as much about the agronomics of the individual species and plant diverse mixes and let your conditions tell you what will and won't work. Don't spend too much money on any one particular species, but have enough diversity out there so that if one of those species is a complete failure, the cover crop itself can still be a success because of the other components in there.

58:36 Now visit our website and that's why we have it on there, that's why we have that information on there for you guys to use. And I want to also shout out to Jerry, he is on here. Jerry Lawners, oh yes, the picture of that role—beautiful world cover crop with hairy vetch in the corn. So yeah, thank you for that, Jerry. Yes, and beautiful crop. When I impressed, one of the most impressive pictures in my repertoire. Thank you for sending us that series of photos.

59:15 Question from David says, what levels of organic matter do you like to see in cropland, and what levels in pastures? I think your sweet spot really for both is between five and ten percent. I think there's some diminishing returns once you get above ten. I mean, there are, you know, highly organic again, like peat soils, muck soils that are 50 percent organic matter, 25 percent organic matter, and once you start getting over about 20 percent organic matter, you actually start having problems with the availability of some mineral nutrients. Things like copper come very unavailable, and sometimes you have to foliar apply copper on soils with excess levels of soil organic matter. Now those are in drained wetlands. You know, it took centuries to build up that organic matter. In a field soil, I don't think we're within our lifetime or our children's lifetime or grandchildren's lifetime, I don't think we'll be in the situation where we have to worry about too much organic matter. But a lot of people tell me that once you get above about four percent organic matter on a clay soil, and I've seen this happen, the soil just changes. It changes the nature of it. It doesn't look like the same soil it used to. And those of you who have taken soil organic matter levels from you know one or two percent to four, five, six, you know, chip in here and give us your observations. But mine is that there seems to be a threshold of about four percent on a silty clay loam, you know, a fairly heavy soil. Once you get above that for organic matter, things just change. Everything just really starts to work. Things become easy. And please share your observations out there.

1:01:26 Yeah, well with that, we are going to wrap up. If you guys have any other questions, feel free to email Dale at greencovers.com, and there's his cell number: 756-142-0031. Thank you guys for tuning in. Like I said at the beginning of this, if you think you're joining halfway through or anything, we are recording all these, so they will be posted to the website. And that can be found at greencoverseed.com and you'll just search webinar there. So with that, thank you so much Dale for your time, and I'm sure you'll get all kinds of questions tomorrow.

1:02:06 Thank you. Thank you for facilitating this. Yep, no problem. Next week, thanks everybody for watching. Yeah, next week we'll have a little more in-depth look at annual warm season cover crop species. So we're going to talk about some of the characteristics of individual cover crops. So thank you guys, enjoy your week, and we'll see you next Tuesday.