Yates Adcock, far left, answers a question while (l-r) Allen Williams, Alan Mindemann, Jimmy Emmons and Terry Forst listen at the Southern Soil Health Conference. “Open your eyes and think and look and see what’s going on, because it’s really pretty remarkable what you can do with a rest period,” on a portion of rangeland, Adcock says.
A panel of no-tillers, both new and experienced, from through the Great Plains and southern U.S. engaged in some in-depth discussion about cover crops, pasture and rangeland management, herbicide carryover an other important no-tilling issues during the most recent Southern Soil Health Conference.
Speaking in Ardmore, Okla., the panel included Steve Tucker of Nebraska, Travis Isbell of Texas, Colorado’s John Heerman, Oklahoma’s Alan Mindemann, Yates Adcock, Jimmy Emmons and Terry Forst, and Mississippi grazing consultant Allen Williams, along with moderator Keith Berns of Bladen, Neb.-based Green Cover Seeds.
Herbicides and Covers
What herbicides do you use on your wheat?
Jimmy Emmons: We don’t use any herbicides on our wheat because I want the option to plant cover crop seed, and if we do that, that limits us. So since we’ve went into our rotation with cover crops and have seen our weed pressure has gone down. So we don’t use any.
Alan Mindemann: In some fields we have wild buckwheat problems and we’ll come in with something like a generic Harmony, something with no residual to take care of that. Like Jimmy said, we don’t limit ourselves by using long residual herbicides in wheat because we’ll almost always plant something after the wheat.
Yates Adcock: We don’t obviously do herbicides for wheat production because we don’t combine or go that route. But on these summer cover crops, the stretch that we had on the moisture we went ahead and planted and sometimes we do spray a little bit of 2,4-D around, which I don’t spray anything like I used to. But that really created an issue in terms of adjacent fields and drift issues.
Where you put summer crops with a broadleaf/legume mix, drift is a tremendous problem. I just really caution people on that for adjacent fields.
Working with Lime
Do you incorporate lime into the soil or do you leave it on top of the ground — and if left on top, how long does it take the lime to get into the ground?
Alan Mindemann: I’ve been no-tilling for 20 years, that’s how I started my farming career. I don’t do any tillage so we put the lime on top. We’ll put on 2 tons at a time until we’ve got the field where we want it, usually 2 tons per lease term, which is 3-5 years, and then we just put it on top.
The effectiveness is determined by how fine it is and how much rain you get. At one point we put on 2 tons and then we got 22 inches of rain in the next month. We got some action on that. It’s just a matter of rainfall to get it in. Usually the pH problem is always in the top 2-4 inches anyway.
Jimmy Emmons: We addressed that problem the first year I bought some new farms and my consultant said, ‘Well, you got to work that in,’ and I said, ‘I don’t know how I’m going to be a no-tiller if I work that in,’ and he said, ‘What do you think’s going to work?’ And I said, ‘There’s one way to find out,’ and since then he’s recommending all of his customers do it no-till.
Keith Berns:I think what a lot of people find is the biological activity. The more biologically active your soils are, the faster that lime will be effective as well. So if you’re just starting no-till and just starting some of this it may take a little bit longer, but give it a little bit of time and it will work. We know scores of no-tillers who are not incorporating their lime and it works very well.
Q: You said that a long period of fallow is starving your soil biology. What is your definition of long-term fallow in terms of days or months? What’s your definition of long fallow?
John Heerman: I’d say anything more than a couple weeks is considered fallow, but in my area some of the longer periods, if you think about somebody combining wheat in July and they aren’t going back to corn until the next May, that’s 9 months that ground’s just laying there and no plants are photosynthesizing. You don’t always think about the fallow between the crops, you think ‘Oh, winter’s coming,’ so you don’t count those months. But you have to think about the periods in between crops. It’s just not the long fallow periods.
Steve Tucker: I’ve just seen rotations change immensely and now we can implement cover crops, we can start implementing cattle. The doors now are just opening up and that’s what’s exciting about the possibilities of utilizing sun energy. I’ve talked about it earlier, that sun is giving free energy and we’re not utilizing it. It’s called the sun splash. When it hits pavement it’s not used. Why don’t we utilize what God has given us and grow something with it?
Keith Berns: A lot of people ask if we know how long does a cover crop have to grow in order to be effective, to get my money’s worth out of it. And when we’ve asked some soil microbiologists, basically they’re saying if you can get at least 3 weeks of growth you’re having significant root growth and significant carbon being put into the soil.
Economically it’s probably not quite worth it with just 3 weeks of growth. We would really like to see 5-6 weeks of growth, but we’ve had people do cover crops that they only let them grow for 30 days and then they terminate it or graze it or do something to go to the next crop. But if you leave that soil bare with nothing growing, you’re certainly going to hurting your soil biology.
Q: Is there a cover crop that can be planted in coastal Bermuda grass in the spring? My cowpeas were choked out last year by the coastal. So for any of you that are working with Bermuda grass, what types of things could you inter-seed in the spring? And we also have a question here about interseeding maybe even later in the fall. So for you folks that have Bermuda grass pastures and have been working with planting some covers in that, either in the spring or the fall, why don’t you just talk about what you’ve seen work or what you think might work.
Alan Mindemann: Late, early winter — or early winter seeding of small grains will work in Bermuda. Very early spring oat plantings will work. You’ve got to have enough time because Bermuda is so competitive it’s really hard to get anything started in Bermuda once it starts to green up. You’ve got to get in there before and let that forage get a jump on it. And even then, by the time the Bermuda greens up it will be starting to compete with whatever’s even ahead of it by a month or more.
Allen Williams: Yeah, you can pretty much do anything you want to in the fall, with cool seasons. And that’s typically done all through the South so you can come in with about any kind of cool-season mix that you want, and it’s going to work very well. But I agree with Alan, if you’re going to get anything in during the spring, the earlier you can get it in the better to outcompete.
Keith Berns: So the key to getting anything established into a perennial is you’ve got to pick the time when the perennial is the most dormant and has the least amount of growth — because if they’re both growing the perennial, or the established plant, will always win. So you always want to attack it at its weakest point.
You’re not trying to kill it, you’re just trying to use the season that it’s not growing, so wait for it to go dormant, or like they said, plant as early as you can in the spring. It’s probably easier to get cool-season things growing into a dormant warm-season pasture than the other way around. So you folks that have Bermuda have a lot of opportunities with that.
Q: Allen Williams commented about reduced inorganic — you’ve reduced inorganic inputs by 55%. Please discuss the tradeoff of using inorganic inputs to build soil biology vs organic inputs to build soil biology.
Allen Williams: As we all know, particularly when we use inorganic nitrogen we can get caught in the trap of with high-use applications. We’re going to acidify the soil, then we have to come back and lime, and it just becomes sort of a vicious cycle. But basically what we’re looking at is by building soil biology and you’re implementing, of course, nitrogen-fixing legumes in our cover crops, coupled with nitrogen-fixing bacteria. So the more that we can build that soil microbial activity, the more nitrogen that we have available in the soil.
We’ve been able to come in and particularly reduce those nitrogen inputs quite significantly. And we have some data where in growing corn crops we’ve been able to reduce nitrogen inputs by 70+% and have equal or slightly better yields than when we were using 100% of the recommended application.
Q: How much have you decreased your fertilizer on your cropland?
Steve Tucker: I would say about this time I’m about half from where I was at. It depends on the field. And the history of it where I’m at. I’ll tell you the biggest thing that has helped is adding yellow field peas into that rotation. That’s something I didn’t talk about in my presentation, but the ability to put in a legume.
The rotation my grandfather had for years was wheat and summerfallow, and we started putting corn into it. Those things you don’t get much benefit from. You got to put a legume back into the system and then a legume with cover crops. And I think now adding cattle and livestock into the equations is going to put a whole another dynamic into it.
Q: Should I fertilize my cover crops?
Keith Berns: The answer is it depends. It depends on what your goal is. If your goal is to produce the maximum amount of tonnage for grazing then yeah, you’re probably going to need to add some, especially if you’re going into a soil that has very little residual nitrogen. It all depends on what your rotation has been, what your soil health is and what your goals are.
Oftentimes if we’re not going to graze a cover crop we rarely will fertilize it, we want to make it work on its own. But if we’re doing that, we want to have enough legumes in there so it can produce its own nitrogen. And that’s going to cost a little more. A mix that has a fair amount of legumes is going to cost more than a mix that doesn’t, because legumes are just must more expensive seed.
So there are situations where we do recommend putting some fertility with cover crops, particularly if you are really dependent upon the grazing tonnage. But once you get into a system like this and you’re grazing, 80% of the nutrients from that cover crop are going to go right back into the soil if you’re grazing it.
If you hay it, 100% of those nutrients are leaving the field unless you bring the manure back. And if you’re taking a grain crop off, probably 75 or 80% of nutrients are leaving the field, and so those have to be replaced.
So a lot of it has to do with the type of system that you’re in. A heavily grazing based system will need far, fewer inputs. Maybe not at first, but eventually once you kind of get that system into equilibrium and get it going.
‘Resting’ Your Land
Q: For Yates: Would you be willing to talk about the Sabbath year rest and soil forage health?
Yates Adcock: You don’t get to hear about this very much. But the Bible gives a pretty good illustration of rangeland management — just land management. And it’s in Leviticus and it talks about how to set that land aside and let it rest.
And under that protocol, every 7 years let your land rest. And Nancy and I thought that was pretty unique, and we thought, well, it’s pretty hard to let everything lay out in 7 years and maintain a cow herd. So we went through there and we kind of took some of these farms and we let 1/7 of the farm just be stripped off and not grazed that year.
Now keep in mind I want to infiltrate some of the pressures that I’ve had to work under. One comes from my education is maximize production, efficiency and ramp all that up as educated from one of the major land grant universities in the 1980s. So that’s what I came through. And I also worked under an individual that if there was anything left on that field, well you wasted that! Now probably every one of you know what that is, so those were some of the mindsets that had to be overcame.
I guarantee you, standing grass is never a waste. And when that one-seventh of that land was laid out, and it’s real easy to do, just figure out what it is, stretch a hot wire across there and just don’t graze it that year. And I’ll tell you what, go back in there the first part of the next year, roll up your fence or just open the gate and put some cows in there. But you need to walk across it first because it’ll walk across different than the rest of your land.
First off, it’ll feel like you’re walking on something that just got a new carpet, but got a double pad underneath it. Boy, it’ll be spongy, it’ll be soft feeling, and it will produce like you cannot imagine. And I say that from the standpoint when you bite that off and you leave that residue and go to the next paddock, the recharge rate on that grass outperformed the rest of our fields. It really opened my eyes what a rest period can do. It’s really interesting.
Open your eyes and think and look and see what’s going on, because it’s really pretty remarkable what you can do with a rest period.
Terry Forst: Back to my native grass management, which I don’t have the same concept on my fields as I do on my native grass. We rest. We aren’t a high-intensity rotation like Yates, but we rest a lot of our pastures and even through the drought, even through this whole time, we have grass.
And Yates is right — rest really will pay off. Our calving pastures that we choose to calve in, we will pull cows out and we will not be back in there until they calve again. So that’s almost a year rest.
Keith Berns: And I’ve had people ask me this question as well, and the biggest fallacy that I think some people are under is that in order to rest a piece of ground you have to have nothing growing on it. Almost like summerfallow. Worst thing you could do to rest a piece of ground.
If you really want to rest a piece of ground, you got to have plants growing on it. Just don’t remove the nutrients from it. Let it grow, let it cycle, let it go back into the soil. That’s what’s really going to make that improvement and really help it.
Jimmy Emmons: We had a lot of discussion earlier today about compaction, whether it be cattle or equipment, but it’s exactly what you say. Once you lay that out you really help that sponge, and really help that cushion and you won’t see the impact of the cattle or driving on it, even.
Q: Here’s a follow-up question on letting the land rest for a year. If you let the land rest for a year, is there any particular crop that you would plant for the rest so it’s not laying bare.
Alan Mindemann: Alfalfa or maybe a yellow clover, a biannual, it’s a 2-year thing — something that will grow continuously. In our country it would be something like an alfalfa would stay green through most of the winter, it’s a cheap alfalfa seeder.
John Heerman: I would probably put a cover-crop mix in of warm- and cool-season broadleaves and grasses. If you got those in early enough, some of those would probably go into seed production, reseed themselves and come up and grow as another plant. But with those different warm- and cool-season plants in there you can bridge your growing gaps, and when the frost comes and the growing conditions aren’t right for that one plant, the other plants will start taking off.
Q: For seeding into heavy cover, what types of drills or seeders are best, are you using coulters, and how do you get thru all of that stuff?
Equipment For Seeders
Alan Mindemann: Just a single-disc opener is what I prefer. Case IH has got a great machine, John Deere’s got a good machine, too. I’m sure there’s a few others out there, but I much prefer a single disc over a double disc.
Jimmy Emmons: I’m in the minority today. I use a double disc, and the reason was cost up front. I mean, it’s all about everything else in life, it’s about timing. If we have a lot of heavy-duty material like we’re talking about, green is better to cut thru then sprayed and having to wait 2-3 weeks before that starts getting woody.
Keith Berns: We get that question a lot and our standard answer for what is the best drill to no-till with is it’s one that gets it in the ground and can get the seed covered up. And that can come in just about any color. One of the biggest keys is you got to have very sharp blades and you have to have enough weight on your drill to get those blades in the ground.
And when you first start no-tilling, or if your ground is exceptionally dry, you’re going to need a lot of weight. The longer you’re in no-till, and the more mellow your soils become, the jore you’ll be able to start backing off that some.
Alan Mindemann: The ideal is to not have to cut through much of anything. Just well-managed, upright residue is the best to plant into.
Keith Berns: Yeah, and upright residue is the key because it’s much easier to plant into something standing than something laying down.
Q: What kind of alfalfa do you use? A lot of people have concerns about grazing alfalfa. You mentioned you had alfalfa in your mix.
Travis Isbell :I think it was just the common alfalfa. I think the origin said it was from South Dakota or something like that. But I wasn’t real worried about it because I figured it’s just going to be a waste of money and I’ll never have to worry about it, but it proved me wrong. I failed to mention, too, that was the second year that it was growing, so I would assume it would come back, they say 4-5 years, so hopefully we can get a little more production out of it.
Jimmy Emmons :Jim Johnson and I talked about it this year. It’s all about diversity, and if you had all 100% alfalfa there is some risk there. But if you put that in a mix, regardless of whether it’s sorghum sudangrass, grazing corn, alfalfa — if you put that in a mix, cattle are just like us in a buffet line. If they take a bite of something and it makes them feel a little bit queasy, they’re not going to select it. They’ll select through that, and that’s the great thing. You want as much diversity in the mix as you can get.
Q: A follow-up question. Since livestock can be somewhat selective, how concerned do we need to be with prussic acid, nitrates, bloat, etc. in a diverse mix?
Jimmy Emmons :Well, this summer when Jim Johnson from the Noble Foundation came up we went out and watched the cattle graze and that was a 14-way blend. His concern was some of the acid in drought times and we watched them and — I don’t know if the rest of you guys have seen it, I’m sure you have, how a cow will rub her nose up the side of a leaf. And the debate Jim and I had is she smelling it or she’s absorbing some of the test in her saliva?
There’s something about how they select that when they’re going through that mix. And I still say if there’s some toxicity in something she samples, they’re just like us: if something doesn’t taste good on the buffet line, I’m not going to eat any more of that because I’ve got 6 or 8 or 10 more species to eat on.
Allen Williams :What we’ve found is that where you have those issues is where you have basically a monoculture or near monoculture, but when you have a pretty diverse mix we rarely ever have any issues with nitrate or prussic acid, anything like that. That’s one of the beauties of moving cattle around less frequently is you have more time to actually observe what they’re doing and how they’re grazing as you turn them into a paddock.
And if you pay attention to that they will do that very thing. And a lot of that goes back to what I mentioned in my talk this morning about not only the primary nutrient compounds, but those secondary and tertiary nutrient compounds. They put out chemical signals that these cattle can pick up, and when they have that opportunity to make that selection they will absolutely do that.