Sugarbeet nutrient management
Paul McDivitt:
Welcome back to University of Minnesota Extension's Nutrient Management Podcast. I'm your host, Paul McDivitt, communications specialist here at U of M Extension. In this episode, we're talking about sugar beet nutrient management. We have three members of Extension's Nutrient Management team, and a special guest. Can you each give us a quick introduction?
Dan Kaiser:
This is Daniel Kaiser. I am a nutrient management specialist with the University of Minnesota Extension. I specialize in nutrient management guidelines for the majority of our commodity crops across the state of Minnesota.
Melissa Wilson:
Hi, I'm Melissa Wilson. I'm an Extension specialist and associate professor in Soil, Water and Climate. I deal typically with manure nutrient management.
Lindsay Pease:
And I'm Lindsay Pease and I am a nutrient and water management specialist with the University of Minnesota. I am stationed in the heart of sugar beet growing country in Minnesota, in the Red River Valley. I work out of the Northwest Research and Outreach Center in Crookston.
John Lamb:
And, I guess, I'm John Lamb and I'm the special guest. I'm a professor emeritus in the Department of Soil, Water and Climate. I've done a lot of research in sugar beets since about 1984. I retired about seven years ago. And that's where I'm at.
Paul McDivitt:
Great. So starting off, how did Minnesota become the nation's top sugar beet producer?
John Lamb:
Minnesota has traditionally been a sugar beet producer. I think a lot of it goes back to about 1900s. It came with the growers in Red River Valley and also a bunch of growers in southwest Minnesota. They raised beets since that time, basically either for American Crystal Sugar as the company formed. The group in southwestern Minnesota used to haul to a plant in Chaska. And then in about 1974 or five, the Chaska plant closed. And they built their own plant in Renville, Minnesota. In the Valley, American Crystal became a co-op around that time, I believe. And then also down in Breckenridge area, Minn-Dak Cooperative started. And so there's a number of processing plants up in the Red River Valley.
Sugar beets account for about half of the sugar that we consume in the United States. Of that, we grow, between the Red River Valley, which includes North Dakota, Minnesota and also in the south central part of Minnesota, we grow about a quarter of the nation's sugar. And so we have a long history of that. All of the processing plants are farmer-owned cooperatives.
Dan Kaiser:
So John, is there something about the soils up here? Because if you look at beets, I mean, you look at kind of where they're grown in the US. I mean, we look at kind of our latitudes. It's kind of stretching over to Michigan too, that it kind of seems to be more northern. And you see them in areas particularly more of higher pH. Is there something about that that is better for beets? Or, I mean, how does that work?
John Lamb:
Well, then, it is kind of interesting. Minnesota and Michigan and the Red River Valley are the only dry land sugar beets grown. Michigan soils tend to be a little more acid. The soils in the Red River Valley and southwestern Minnesota are higher organic matter soils. We have cooler temps in the evening that help put on sugar in the fall. That organic matter that we have sometimes can be a problem from a nitrogen standpoint, particularly if we have moist falls where we get mineralization, because nitrogen causes lower sugar quality and more impurities. As you go west in the United States, sugar beets are irrigated.
And then we also have one anomaly. We grow sugar beets. There's about 25,000 acres of sugar beets down in the Imperial Valley, south of the Salton Sea. And of course, they raise those during the winter. In fact, they just wound up harvesting in early August. So when they're planting beets right now, we're harvesting beets. So it tends to be with higher pH soils, but not always.
Lindsay Pease:
And something really interesting about sugar beets that I didn't even realize until I was moving into the Red River Valley region is the area I grew up in, which is northwest Ohio, technically used to be part of the Michigan sugar growing area. It has the same clay lake bed soils. But apparently a lot of those beet growing acres and factories ended up going out in the '80s, going out of business. And I do think it is partially because in Minnesota we have these cold winters that we all like to complain about, but are actually really great for storing a large number of beets. And I think that's something that keeps those factories really profitable, that once you move further south, that window to store beets is shorter and shorter.
Dan Kaiser:
That's one of the things, I think, in growing up in Iowa, I think there were some plants at one point in time in northern Iowa, or I think around the Mason City area. And my dad talks about them delivering beets around Waverly, where I was at. That's been years, and years, and years ago. So it kind of shifted towards, I think, Lindsay, what you're saying, or John, it's probably a storage issue too, because you can see those piles out there. And it gives you some topography relief up in the Red River Valley. When you're driving around, you can kind of think where you see some hills that they're piled beets. But it's interesting, I mean, I didn't get into research with beets until, I didn't realize, John, it's been about seven years since you retired.
It's an interesting crop dealing with, because it's kind of like wheat when you're dealing with that quality issue you were talking about, John, with over application of nitrogen actually being of a detriment, because it results in lower sugar quality. And it's kind of more of a processing issue for the factories. So it's kind of an interesting crop to work with being that again, you've got that quality component to deal with, where we don't necessarily deal with that with corn, where over application and nitrogen just generally doesn't give us a penalty.
Paul McDivitt:
What are some highlights from past sugar beet nutrient management research in Minnesota?
Dan Kaiser:
Well, I think John can chime in a little bit on this. But I mean, a lot of the work has been on nitrogen, because that's really the key component. There's been some work on phosphorous, looking at placement. I think some of that work that, John, I think maybe you were involved and Albert Sims were involved with looking at starter versus broadcast with phosphorus. Some interesting things there, just because beets are grown in areas where they tend to be lower in phosphorus. But starter rates tend to, at times, be sufficient for sugar beet production. So that's the main one I've seen. I mean, been a smattering of stuff here or there on sulfur and potassium. But you're generally in an area where potassium hasn't been an issue and really in a crop that potassium, I don't think, has really been as much of an issue. But John, you might be able to provide some comments on that.
John Lamb:
Well, you're right, Dan. Most of the areas we grow beets in have a natively high potassium content. Also, when they set up some of the quality standards for beets, potassium is contamination when it comes to the refining. So we've always kind of stayed away from it. In recent years, I've done a, did a study where we put tons of potassium on just to see if we could hurt the quality. And we really didn't. So it isn't quite the stay-away nutrient that we worry about. I also worked with zinc. Zinc is one of those crazy ones that you might get one in 20 sites to get a response to. And you think about it, with the soils being mainly higher pH, that maybe could be a problem. Another one we've monkeyed with a little bit is boron. If you're on real sandy soils that are irrigated, sometimes we see a response. But on heavy textured soils...
I mean, Dan, you came back and did a number of studies on boron and on heavy textured soils and didn't get anything. One thing we do worry about with boron is it can be tough on the seed if it gets near the seed. Same way with the work that Albert Sims did on starter phosphorus. The neat thing is we can put three gallons of phosphorus in the row on the seed, not do damage to the seed in the germination, and still, his work showed it was like 60 pounds of phosphate broadcast applied.
Dan Kaiser:
Three gallons of 1034 furrow, it's amazing kind of what that can do, particularly in some circumstances. What's kind of the interesting thing, looking at some of that. It's interesting you talked a little bit about damage, John. I mean, that's been one of the questions I've gotten in the last few years, has been urea spring applied. A lot of growers seeing issues with stand loss with urea. And we've seen that in many of our studies. You look at increasing rates of nitrogen as urea, we can see a significant loss in stand. The thing about beets, I mean, it kind of reminds me a little bit about small grains, is that the reduced stand that they tend to flex a little bit. And you end up with a bigger beet, just because of not having as much competition. And yield doesn't seem to be as impacted, even though stand can be significantly reduced. So it's kind of one of those things that I know growers are worried about it.
So I'll talk a little bit about that when we talk about current research, because we're still looking at that with some of these different nitrogen products. But that's been one of the big things. The big questions I've gotten, particularly from some of the consultants of working with beet growers, is on some of that spring urea. So that's been the big thing. John, you mentioned the boron, that's kind of the questions I've gotten. And we saw absolutely nothing with it. And you could actually see with, maybe where it looked like tonnage was going down slightly with some of our higher rates. So it's one of the things that with organic matter, if you've got high organic matter, I'm just not generally worried about it. If you pull samples and it's dry, I think you're likely to see lower boron content in the tissue, but it's not a whole lot you're going to do about it, because it's dry and that's just likely a thing, a lack of uptake, you get water.
It's kind of what we've seen with alfalfa. In some of the areas that were traditionally boron deficient, you get moisture. And then the symptoms for deficiency tend to go away. So it isn't straightforward. Another question I'd gotten this fall was on sulfur. So evidently, there must be some growers kind of talking more about that. And we've run that. I know, John, you worked with Mark Bradehoft. Had some stuff a number of years ago looking at that and there just wasn't anything with sulfur and beets. I mean, really the biggest concern for growers right now is nitrogen, just because of that trade-off with tonnage and quality. I mean, that's the kind of thing that has to be the bigger focus when you start looking at it. And that's again, traditionally what the, other than diseases, it's kind of what the growers have been interested in. That's what the research is focused on.
Paul McDivitt:
What current studies does the U of M have on sugar beet nutrient management?
Melissa Wilson:
I guess, I can jump in here. We have a current trial. And I actually started working on this with John so he can feel free to chime in. We're looking at manure application in the sugar beet rotation. There's been more and more of these larger dairies coming into the sugar beet growing regions, whether it's up in the Red River Valley, it's also happening in west central Minnesota as well. So there's been questions about, can we get this manure and can we apply it in the rotation and will it affect sugar beet growth? Kind of like John and Dan were mentioning earlier, nitrogen is of concern, particularly if there's nitrogen in the soil late in the season, which traditionally manure is the gift that keeps on giving. And it keeps on giving nitrogen, potentially later in the season. So we wanted to know, can we put it in front of sugar beets? Or, should we put it somewhere else in the rotation prior to soybean, prior to corn, wherever it may be?
So that's kind of what we did. John helped me design an experiment, where we actually have all three crops in rotation. So we applied manure at two different rates one fall. And then we applied, or planted, all three of the different crops that year to kind of see again, where in the rotation should this manure go? So we applied manure that first year. And then we did not apply it the second and third year. We did balance everything with fertilizers though, so we're not looking at nutrient deficiencies. We're just seeing, can we use manure as a nutrient source and replace some of the fertilizer?
Overall, we've been seeing pretty good results, especially with sugar beet. We were thinking that there would be a hit on extractable sugar or purity. And we actually didn't really see too much of that. I guess, we saw the extractable sugar was actually higher in our manured plots, typically, than it was with our fertilizer-only plots. The sugar purity was a little bit lower. But we're talking less than 1% at two different sites that first year after manure application. So overall, I think we're actually pretty pleased. And again, John can fill in, but I think we were happy to see that.
Paul McDivitt:
What year did you apply, Melissa? Was it a dry or wet year?
Melissa Wilson:
So we did this in kind of west central Minnesota. And that trial we applied in fall 2019, which is very, very wet. We were glad that we even got manure applied that year. And then ended up being kind of a normal to dry-ish year in 2020. And then our second site, we applied in the fall of 2020. That was up more, near, getting a little bit closer to the Red River Valley. Or, it was in the Red River Valley. In the fall of 2019, that site had actually flooded out, so that's why we didn't get to apply manure that fall. So that's why we then started the experiment a year later.
John Lamb:
Okay. Historically, we've done manure work in the southern part of Minnesota, because we have a lot of hogs and turkeys. And what we have found a lot of times is we will decrease the quality a little bit. But the increase in tonnage more than made up with the payment systems that are involved. We always went on land that had never been manured. And we only went through one cycle of the rotation. And so that was kind of a base to that. And Melissa's work is looking at this dairy manure, because we'd only worked with turkey and hog before. And so it will be interesting. It kind of defies some of my thinking of the fact that manure is bad and, oh, my goodness, we're we're going to ruin quality. I think we can probably manage it into the rotation. The other thing about manure, it always gives us this tonnage bump. And we don't like to process any more pulp than we have to. But from a grower's standpoint and the payment standpoint, it's still very positive.
One other attribute I would put to with the sugar beet and why we worry about this nitrogen thing, we had a study once where we put on up to 240 pounds of nitrogen into urea. And then we also had a similar with hog manure and with turkey litter. And we followed the nitrate in the soil from right before application through the whole season. And by August, the nitrate underneath all those treatments was the same. And so the moral of that story is, and it's always been known, sugar beets love nitrate. And they'll suck it up. So when you take a nitrate soil sample right about now, October, it'll be the same no matter what your nitrogen application rate was.
Dan Kaiser:
Well, and that's one of the things I think, that's interesting about beets. And John, I mean, those roots, it's a tap root. So and that tap root will go down quite a way. So our recommendations right now for soil sampling for nitrate, I think, are four foot for the recommended rate, although I think we've got some recommendations for shallower. But a lot of that just accounts for the fact that sugar beet's so good at pulling nitrate out of the profile just because of that deep tap root on it. So it's an interesting crop from that standpoint. It's kind of like anything else, if nitrate's there, it's going to take it up. And with that deep tap root, it can extract it out of some pretty deep layers.
In a rotational standpoint, it's kind of interesting, because a lot of times in the south, we'll see it following corn. So that's where I think soil sampling or soil testing becomes important just to know how much nitrate is there. Northern ones generally are following wheat, which wheat will, you see, strip out a lot of that nitrate. At least some, but not as much. You tend to manage a little bit more closely, because of some lodging issues up there. But it really becomes important, especially deep soil cores. And you see a lot more sampling in beets, just because of trying to fine tune those nitrogen recommendations and those deep cores really help to do that.
John Lamb:
Just to add to it, the history of this is back in the early '80s, Alan Kavanaugh, who was an Extension person with both Minnesota and North Dakota did his PhD research on placing N15 at different depths. And they found that by the end of June, the sugar beet root was already mining nitrogen at four foot. And so we know that that is there. And some of that also tells us why we're worried about putting too much on at the beginning. We don't want to put too much on later in the life of the beet, because it's there. It's going to take it. And it's going to ruin our quality.
Dan Kaiser:
Lindsay, what are you working on right now? Because I know you had some projects up north. So, I don't always get up north as much as I'd like just to kind know what's going on up in that way.
Lindsay Pease:
A lot of what we have going on at the Northwest Research and Outreach Center right now is actually a little bit more looking into how you incorporate some of these soil health management practices into a sugar beet rotation, reduce tillage, strip till and cover crops. And that's actually bringing up a lot of really interesting nutrient management questions that I'm hoping to get into, which is when you're kind of trying to reduce tillage or have, let's say you harvest your wheat in hopefully, late August and you get a cover crop growing, the traditional time to apply your fertility is in the fall. And it can be really scary to wait until the spring. And so how you're sort working around these systems, these changes in systems that are going to be modifying a little bit of what the normal practice is, these are all questions that we can draw somewhat from the past research.
Like John Lamb was saying, Albert Sims and his research about the starter fertilizer, what can you apply with the seed, it's really important. But I think there's still a lot of open questions when it comes to that. So that's kind of some of the work that I'm looking to get into next.
Paul McDivitt:
Lindsay, do you know much about cover crops for pre-pile sugar beet? I'm looking at a blog post from Anna, and Jody, and Tom Peters, and Liz Stahl. And I don't know if you can summarize that at all.
Lindsay Pease:
Sure. When you're thinking about planning a cover crop, one of the things that especially gets tough when you're all the way up north in the Red River Valley is, let's say, [inaudible 00:22:42] well, as we're recording this, the last of the beets are, or about half the beets are harvested. But it's already mid-October and there's not a lot of time to establish a cover crop if you're planting in mid-October. So what's nice about the pre-pile acres is that you can actually get out in those areas a little bit sooner. Some of the things that we're seeing though, is that those pre-pile areas are often heavily trafficked. So you want something, that if you do plant something that's going to be a little bit more hearty. I don't know that we ended up getting out much this year in terms of for our research plots, on pre-pile acres, because that was such a big question with the growers.
We kind of said, "Hey, you want to plant some cover crops on your areas?" And knowing that they're going to get beat up, I'm really curious to see how that ended up lasting. But that's sort of one area you can kind of insert into. We do see a lot more cover crops going into beets than after beets. And again, that comes to wheat. And you have a lot more time after the wheat's harvested.
Paul McDivitt:
What else should growers know about sugar beet nutrient management?
Dan Kaiser:
Well, it's one of the interesting things, when we start talking about any of these crops in the state, is that we tend to see a lot of transition, or a lot of grower interest in bringing practices that may work for one crop rotation, say for corn, to beets. I know, John, you had mentioned before we started recording, some of the placement and timing questions that you get for nitrogen, since growers are looking at that more for corn and a lot of them have equipment around there that they can run through the field that if there are any options for that. And the thing about it, these crops, they're different. And with sugar beet with that deep tap root, it can access deeper levels of nitrate. It doesn't make a lot of sense to me on timing, particularly for heavier soils that would be any sort of impact.
The thing that I'm looking at now is urea and urea sources in timing, because it's one of the things in the southern part of the state, fall urea has kind of crept in as a practice for sugar beet application. We know there's some problems with corn with that. I'm trying to see if some of the same issues with beets and with some of the stuff we're looking at right now with sources is to try to maybe get a handle on urea since we know that can have volatility issues into the winter. Some growers think that that may stop when we hit 50 degrees. But with urea, the volatility portion, where we're losing ammonia, can actually occur into situations where the soils are froze, or near that, what that general potential for loss is. We may not be necessarily losing it to the tile lines, but it still represents some loss and kind of some challenges for some of the growers.
So that's kind of one of the things that I'd really say just looking at a lot of this is that when you take your research, you just have to be careful what you do. And if it works for one crop, it may not necessarily work for another. So that's kind of one of the big things, I guess, I would caution some of the growers.
John Lamb:
I'd just like to chime in a little bit here is, back in 2000, we did a bunch of studies that were very similar to what Dan's doing now, looking at fall versus spring urea applications and incorporated the urea. And at that time we didn't see any difference between fall and spring when it came to yield or quality. So we've done this off and on over the last 30 years or so. And we always were encouraging if they had a chance to put it on the fall, they could get away with beets. And we always thought it was because that root is moving pretty fast and we don't lose much to the tiles. We've also looked at split applications over the last 30 years. And the general summation from that over, I must have done 30 or 40 site years on this, is it doesn't seem to hurt your quality if you stay away from late June applications. But it doesn't help either. So I always come back to the economic standpoint as one application trip is cheaper than trying to do two.
And we need to continue in that vein. The growers, like I said earlier, are really interested in that. They're also looking for the silver bullet with the biologicals and even some of the non-biological nitrogen things. Again, we've had some more questions about potassium. You were talking about needs and stuff. We get questions about the potassium now. Micronutrients are always high on the list, anything that they think might enhance sugar. And so that's been a continuing thing. And I think will continue to be into the future.
Dan Kaiser:
And I don't necessarily think it's a bad thing having some of these questions, because the good thing about at least having some of these nitrogen trials is that we can continually add to our database, especially if you have some core treatments in there that are reflective of a response curve. And it's kind of nice to have that. Melissa, your work with manure too, I mean, since that's kind of incorporated into that rotation, it's nice to have that information out there just for growers' questions. And it keeps us busy, just based on the questions we have. But just looking at it, sulfur is the other one too, I get. And it just seems like there's certain crops out there that it makes sense for. Potassium is the same way.
I mean, corn, both potassium and sulfur, if you're taking care of it on that regards, it doesn't seem to, then these crops that are less sensitive deficiencies doesn't seem like it makes as much of a difference to kind of focus on them. So that's one of the things that we've been really looking at with a lot of our research with a lot of the different crops out there is, where does it make sense to make some of these applications? Because some of these crops, you could probably forget it and worry about some nutrients more than others and not have a loss in yield.
Melissa Wilson:
And just a plug for a manure, don't forget, manure is the complete nutrient source. So you are getting some of these micronutrients in the rotation at least once every three years or whatever rotation you're using and applying the manure.
Dan Kaiser:
And one of the other interesting things, I know John, you worked with PCC lime, a precipitated calcium carbonate. I've been getting a few more questions on that too in terms of nutrient availability. I mean, liming-wise, if they give you an ECCE rating on it, I mean, you should be able to use it as liming source. But the question I get more often than not, is are those other nutrients available, particularly phosphorous?
John Lamb:
Well, PCC is the wonder drug of the world in the beets. What we've found with using it that's precipitated calcium carbonate, it's a byproduct of the refining process. So we have these huge piles by each factory. They're trying to get rid of them. And in fact, in southern Minnesota, we've gotten rid of most of the recent PCC. It tends to ameliorate problems with the Attamyces disease. Albert Sims and I did a bunch of work on how does this affect phosphorus, for instance. We'll see an increase in soil test, but we never saw a response. Now, getting a phosphorus response on sugar beets is not easy, because, I don't know, they just don't respond like corn does. But we didn't see much of a response in corn or soybeans in that study, either. But it doesn't hurt.
But you'll get a lot of questions. And at least in the southern Minnesota beet sugar area, how it all got started is because of some herbicide carryover problems that occur with the areas that have a little lower pH. And so they applied it and they saw a bump. And so it's part of the lifestyle, I guess, in the nutrient management down there. But as for the other nutrients, we've never been able to show that in research.
Paul McDivitt:
All right. Any last words from the group?
Dan Kaiser:
Well, I guess, I want to thank John for being on, because as I said, when I was starting here in Minnesota, sugar beets are one of the things that I wanted to really get involved with right away, just because we had enough work going on with corn and soybeans. So it was good to have at least him around when I've been transitioning into this. And it's been good too as we kind of go through. And I'm in the process of redoing some of our publications. I got to get that done here within the next year. But really relying on some of that research that's been done. And just some of the information that you've had kind of going into some of that has been kind of invaluable for some of what we've been new looking at as we've been trying to get through some of these revisions to our guidelines.
Paul McDivitt:
All right. That about does it for this episode of the Nutrient Management Podcast. We'd like to thank the Agricultural Fertilizer Research and Education Council, AFREC, for supporting the podcast. Thanks for listening.
