2025 Badger Crop Update Presentations
The annual UW Badger Crops & Soils Update Meetings present the latest information on agronomic, pest, and nutrient management research coming out of the University of Wisconsin. Here you can find the presentations you missed or want to watch again.
Best Practices to Reduce Agricultural Phosphorus Losses in Wisconsin
Dr. Steven Hall, assistant professor and extension specialist, UW–Madison Department of Plant and Agroecosystem Sciences
Dr. Steven Hall, assistant professor and extension cropping systems and water quality specialist, UW–Madison, explores science-based strategies to reduce agricultural phosphorus losses and improve water quality in Wisconsin. Using SNAP Plus nutrient management software and statewide simulations, the session evaluates the effectiveness of conservation practices such as reduced tillage, cover crops, filter strips, and crop rotation. Learn how these practices impact phosphorus runoff, the role of soil test levels, and how management decisions can help mitigate algal blooms and protect freshwater ecosystems. Practical insights are provided for farmers, consultants, and conservation professionals.
Transcript
0:05
Thanks so much, Scott.
0:06
Really appreciate it.
0:07
I want to start off by thanking you all for being here.
0:09
I know there’s a lot of other places you could be, so we really appreciate you taking the time.
0:15
Like to acknowledge Hava Blair was a really important contributor to this project, who is the SNAP Plus guru, and you’ll see why her contributions were so important.
0:26
Also like to acknowledge a broader group of us, so brighter group of us at UW that’s trying to synthesize the research on conservation practices and how these relate to water quality improvements.
0:40
And, and one aspect of this work I’ll I’ll share with you today is really focusing on sort of scoping out a number of different practices across the state using a fabulous science based tool.
0:54
So, so essentially leveraging the, the one of the key nutrient management tools we have in the state SNAP Plus.
1:01
So we’ll we’ll jump right in.
1:04
So I’m going to be focusing on phosphorus, right.
1:07
So why do we care about phosphorus?
1:09
You all probably are are aware that it is really the, the dominant nutrient that is controlling algal blooms and fresh waters, right?
1:17
So around the state, we’re familiar with scenes like this, unfortunately that have been cropping up for a number of years now, right?
1:24
We when the conditions are right, we can have these nasty algal blooms.
1:28
And so really getting a handle on phosphorus is the best way that we’re going to be able to address this over the long term.
1:36
So a shot from Lake, Lake Winnebago recently.
1:41
So what what we’re really interested in doing is, is leveraging the the Snap Plus nutrient management software to scope out a whole bunch of different scenarios.
1:52
How how many folks in the audience, at least half of you, right.
1:56
So you all are familiar with this tool.
1:58
So I’ll just briefly sort of reiterate what’s going on under the hood actually, right.
2:03
So, so under the hood what what Snap Plus is doing is simulating phosphorus losses from these AG systems using both the management data that you put in a physically based understanding of erosion and climate.
2:17
That’s that’s driving that model.
2:19
And So what we end up with is in our P index is the estimated phosphorus loss in pounds per acre per year.
2:27
And so a key point is right, no model is perfect, but this model has been calibrated with a couple 100 site years of edge of field observations from Wisconsin farms of P loss and it does a, a pretty good job.
2:42
So you know, we can’t necessarily trust this model to predict the actual values of P loss from any particular field in any particular year, but over the long run it’s directionally correct and the model is continuing to improve over time.
2:58
And, and So what we did is to sort of game out over 100,000 simulated fields where we essentially look at a variety of sort of business as usual cropping practices and then start turning levers of various conservation tools.
3:15
And just to emphasize and what we’re doing here, we are interested in the amount of phosphorus that’s leaving the field.
3:22
We’re ignoring what happens to the phosphorus after that, right.
3:26
So in terms of long term water quality, that ultimate transport from field to stream to to river to lake is, is important here.
3:34
We’re just focusing on what you all can influence right on sort of the farm farm scale.
3:41
So, So what we did as as part of this exercise is to chop the state up into these agricultural statistical districts.
3:48
So 9 districts across the state.
3:51
So this is useful because we have good crop yield data that’s aggregated over time from these different districts.
3:58
So we can use these values to get a good estimate of how much nutrients are getting hauled off of each individual field from different kinds of cropping systems.
4:08
We also use this as a way to pick representative agricultural soils, right, to really encompass the diversity of soils across our state.
4:18
So for each one of these districts, we picked out the three most extensive ag soil series and representative map units of those series.
4:28
So as an example, right over here in East Central Wisconsin, the Kewaunee silt loam is is one of the most predominant series about 18% of agricultural land in this region followed by the Hortonville silt loam about 10% and the Manawa silt loam about 9%.
4:48
So together, right, these three soil all series make up over a third of the overall area.
4:54
So reasonably representative.
4:57
I’ll note that we also did additional exercises where we focused on specifically erosion sensitive soils.
5:04
I won’t get into that here specifically for this region, but at the end of this, we’re going to zoom out to the statewide scale and look at some of those more erosion sensitive soil series.
5:17
So in in sort of the exercises that I’ll talk about for each one of these soils, we set it up with a variation in soil test phosphorus.
5:26
So you know, down to 25 PPM, you know, pretty close to the agronomic range.
5:31
Chris Bandura is going to talk talk to us more about soil test P recommendations later on.
5:37
But this is a kind of a sweet spot soil and then 50 PPM, right.
5:42
So above sort of the agronomic range, but still very typical for our for our regions and up to 100 again high, but you know, relatively common in in systems that are receiving a lot of manure.
5:56
OK.
5:57
So in addition to sort of all of these different soils, soil test phosphorus, we’re looking at a wide range of different cropping systems.
6:05
So continuous corn, corn-soybean, corn- soybean-wheat for dairy systems, continuous corn silage, corn silage-alfalfa and pasture.
6:16
So for today, just to try to keep things simple, I’m going to focus on on corn and bean and, and really have, you know, a couple of different tangents, but just just try to keep it simple.
6:26
If folks have questions about other, other systems, happy to entertain those.
6:32
So we were really interested in looking at the leverage of changes in tillage practices.
6:38
So as our sort of baseline business as usual, we had a three-pass chisel plow system, so reasonably intensive but also relatively common across our region.
6:50
We compared this with a vertical till system, strip till and no till systems as well.
6:59
We also looked at differences in phosphorus rate, source and timing.
7:03
And so as I mentioned before, for each one of our districts, we’re looking at average crop removal rates of phosphorus at sort of average yield levels.
7:13
And so that was sort of our baseline scenario, just apply phosphorus at the removal rate.
7:18
We compared this with a 20% reduction as well.
7:22
We looked both at commercial fertilizer and liquid dairy manure and then application in fall or spring.
7:29
And so in all of these scenarios we are timing the application with the timing of tillage, right.
7:37
So to up to incorporate that added phosphorus, OK.
7:42
We also looked at a a whole host of cover crop treatments.
7:45
So our baseline was a no cover crop scenario.
7:49
We also had an October drill seeded rye, a September drill seeded rye.
7:54
Again pretty optimistic for for grain systems, but you know maybe more reasonable for for corn silage.
8:01
And then in August, aerial seeded application, in sort of pushing the envelope, but looking more at what might be feasible as we move into the future.
8:12
We also looked at filter strips for those that are not familiar.
8:15
This is the practice of taking out a strip of cropped land next to a waterway and planting this with perennial vegetation.
8:25
This serves to trap sediment that might be flowing across the field surface, right?
8:30
Allow that to settle out and trap the sediment that’s a so or drop the phosphorus, excuse me, that’s associated with that sediment. As I mentioned, right, we’re looked at, you know, different rotation systems.
8:45
But specifically one way to think about this is taking a business as usual corn and bean system and to ask the question, well, what if we were to get really adventurous and throw an additional crop into the system like an overwintering wheat crop to provide some more green cover.
9:02
If, you know, maybe we have a continuous corn silage system, what would the benefits be of adding alfalfa to that system or maybe take a corn silage alfalfa system, take a portion of that ground and put it in a continuous pasture.
9:17
So these are the kinds of comparisons that we’re that we’re thinking about.
9:22
OK.
9:22
And so I’ve thrown thrown a lot at you.
9:25
And so what I’d like to do is start off with a relatively well constrained group of scenarios.
9:31
So we’re going to focus on a single soil type.
9:34
So the Kewaunee silt loam with chiseled disc tillage, so relatively intensive tillage, but you know, pretty realistic for a lot of fields, no cover crop, no filter strip.
9:47
But what we’re going to do is allow soil test phosphorus to vary.
9:51
So we’re going to have scenarios with both low, you know, 25 PPM, 50 PPM and then up to 100 PPM of phosphorus.
10:00
We’re also going to throw in some variation in phosphorus rate form and timing.
10:05
And so if you do some multiplication, we’ve got three soil test, P levels, 2P sources, 2P rates, 2 timing periods.
10:14
We look at all the combinations.
10:16
This gives us 24 individual fields to start off with, really just to give us a sense of variation across sort of this this landscape before we start turning levers on conservation practices.
10:30
And so I’m going to be showing you all a number of these box plots just to get everyone on the same page.
10:37
When we’re looking at these box plots, the box is spanning the middle 50% of the data, right?
10:44
So half of the observations are going to be within that box.
10:48
The X is the overall average value, that thick line is the median value, the middle number.
10:55
And then each one of these little dots is the result from an individual field.
11:01
So these are sort of our baseline scenarios.
11:05
And so we’ve got some variability.
11:06
On average our, our P index is about 3 1/2, so 3.5 lbs per acre per year lost from these scenarios.
11:15
So not, not terrible, right.
11:17
So if you were writing your nutrient management plan, you’d below that threshold, you’d be below that threshold of 6.
11:23
So it’d be OK.
11:24
But I think there’s ways we can we can further improve the situation. On the higher end, these are our fields that have that higher soil test phosphorus value of 100 PPM.
11:36
The lower end, we’re down at 25, right?
11:39
So that’s one of the main factors that’s driving this initial variability that we see.
11:44
OK, so now we’re going to start turning levers.
11:47
So on the left hand side of this figure, this box plot with the chisel disk, this is the baseline group of scenarios that I was just showing you on the last slide.
11:58
So what we’re going to do now is move to the right across categories of decreasing tillage intensity, right?
12:06
So moving from chisel disk to vertical till to strip till down to no till, right?
12:13
And you can see those P index values steadily decreasing, right, with that decrease in tillage intensity, right?
12:20
Not terribly surprising, but I think one of the interesting findings across, you know, many of the scenarios that we’re running was the, you know, really the benefits of strip till systems, right?
12:31
In many cases we’re achieving P index values that are pretty close to a no till system, but we’re still getting some of those agronomic benefits of tillage, right.
12:41
I think really highlighting, you know, strip till as a, as a beneficial practice to consider and to improve, improve these, these P losses.
12:53
I’ll also emphasize right, when we look at these no till categories, we’re below 1, you know, for almost all of the scenarios, again, to emphasize that even when we’re considering soils with relatively high soil test phosphorus, so 100 PPM, by essentially keeping that disturbance down, we have this large phosphorus source.
13:15
But without that phosphorus transport, right, we’re really able to keep these losses relatively low.
13:22
So some key, key benefits there, OK.
13:26
And also, you know, emphasize, right, I’m going over a lot of stuff, so feel free to interrupt me with questions.
13:31
Happy to take questions as they come up.
13:34
OK, shifting from tillage into cover crops.
13:38
On the left here we’ve got our no cover crop control.
13:42
Moving to the right, we’ve got our October drill seeded rye, our September drill seeded rye and then our August aerial application of that of that rye seed.
13:54
And so one of the, the striking findings that we find across many of these scenarios is relatively little change in phosphorus loss when we’re comparing our no cover crop versus this October drill seeded rye.
14:10
Yes, please.
14:15
That’s so there’s no, there’s no till, there’s tillage before the seeding was done if it was one of the fall seeded scenarios.
14:22
So that’s that’s a great.
14:23
All right, let me actually repeat the question.
14:25
The question was, was there tillage associated with that application?
14:31
And so, in all of the cover crop scenarios, the tillage happened before if it was happening in the in the fall.
14:37
So the tillage is sort of matching the the cover crop system.
14:41
That’s a great question.
14:42
So and anyone have a guess as to why in many cases we’re not getting so much of a phosphorus benefit from this October drill seeded rye?
14:52
Anyone want to hazard a hazard a guess?
14:57
Absolutely.
14:58
So that the comment was for those on Zoom, the drill has some disturbance and not much growth.
15:03
Bingo, right in, in some of these scenarios, we’re actually seeing the P whoops, the P index increase due to that October drill, right?
15:12
That’s that physical disturbance of that field pass with the drill.
15:16
And you know, especially here, you know, as we move north, north in the state, right, we don’t have a lot of growing degree days after getting that cover crop in the ground.
15:25
But the key point is I’m not telling you all not to plant cover crops, right.
15:29
And so we think about the whole picture, we can still get some substantial benefit for nitrogen, right?
15:35
So even if we don’t get a lot of above ground growth from that late, you know, late seeded cover crop, we can oftentimes have substantial root biomass that’s still able to scavenge some nitrate, especially as we move into spring.
15:51
So I think maybe the key take away is, is yes, please plant cover crops, but the more you can think about strategies to get those cover crops on early, get some more residue production in the fall, the more benefit we can have for phosphorus reduction.
16:06
So moving into September, but especially moving into the future, right, If you want to get creative thinking about drones and other ways of getting that seed on early, we can have some tremendous benefit by allowing that cover crop to establish underneath the canopy of your main crop and it can really take off, right.
16:26
You know, we have that that change in in weather at the end of the season, right, where temperatures really begin to plummet.
16:33
If you can take advantage when we still have some warm conditions to get that cover crop established and growing.
16:41
Great.
16:41
The question was, is the seeding rate constant?
16:43
Yes, Sir.
16:44
It it, it was, yeah.
16:45
We tried to pick something middle of the road and of course, I’m, I’m blanking on the exact number, but we’re we’re looking at something that’s sort of most, most plausible.
16:53
Obviously, folks are playing with a wide range of seeding rates.
16:57
We wanted to do something that wasn’t too extreme and in either direction, but I can, I can look that up.
17:02
OK.
17:04
Any, any other questions before we keep rolling?
17:07
OK, the the filter strips, right.
17:09
So this is where again where we’re taking about 30 feet of of ground out of production at the edge of the field and planting that to perennial grasses.
17:18
And what you can see is a fairly dramatic reduction in the phosphorus index which we expect.
17:24
So these filter strips are trapping sediment.
17:28
One important point to, to emphasize is that we’re not trapping the soluble phosphorus form, right.
17:36
So there’s two sort of major flavors of phosphorus that we often measure.
17:41
So the particulate phosphorus that’s bound with the soil particles and the soluble phosphorus that’s moving in the water.
17:48
The filter strips do a great job with particulate, not so much with the soluble.
17:53
And so that’s really what’s remaining, what’s, what’s flowing through these, these systems.
17:58
Another key point to emphasize is that these filter strips, they’re, they’re great in terms of water quality, but from an agronomic perspective, these are not addressing the underlying causes of soil loss and phosphorus loss.
18:12
So, I think, you know, ideally, we’d be pairing these with other in-field management practices to help you keep that phosphorus in place where you can actually use it.
18:23
OK.
18:23
So in terms of, you know, overall rotations, we looked at these corn, soybean business as usual versus, you know, more adventurous producers that are throwing in winter wheat as a as a third year in their rotation.
18:38
And we can see some really substantial benefits, right.
18:41
In many cases, we’re cutting that phosphorus index in half and, and I’m curious right to, to, to get your, to get your, your opinions here, right.
18:50
I just showed you in the last slide that sometimes we’re not getting a great benefit from drilling a rye cover crop after the grain, but yet you know we’re planting winter wheat and we’re getting much more benefit in terms of P losses.
19:07
I wonder if someone has a has a guess as to why this winter wheat system is performing so well in terms of P reduction.
19:17
What’s what’s different about winter wheat versus a like a rye covered crop?
19:22
Yeah, so earlier, earlier, so the statement was we want to get that winter wheat in between the first before the 1st of October, so earlier planting.
19:31
Excellent point.
19:32
What what else, please, Sir?
19:35
Seeding rate.
19:36
Yeah.
19:36
So the seeding rate is is often times going to be a little bit higher.
19:40
What what else?
19:41
What about the spring?
19:42
What’s different in the spring?
19:44
So a traditional rye cover crop, we’re going to kill that off and then plant our grain right.
19:50
And so we’ve got this vulnerable period
19:53
right, where the soils are exposed, whereas the winter wheat right, keeps on going.
19:58
And so that March, April, May period
20:01
when we’re most vulnerable to phosphorus losses, that wheat is really picking up steam.
20:06
And so I think that is one reason why these, you know, these three-year rotations perform so well despite the fact that, you know, wheat is there just.
20:14
One year of this rotation.
20:16
So again, something to consider if you have adventurous growers that you’re that you’re working with.
20:22
OK, so how about phosphorus application rate?
20:26
And so if you’ll recall, we had scenarios where we’re applying P at the crop removal amount as well as a 20% reduction.
20:34
And so if you squint at these figures, you don’t see much difference at all.
20:39
And so I’d like to pose to you all, so why, why do you think, why do you think reducing phosphorus rate doesn’t necessarily have much leverage on these phosphorus losses?
20:52
And so that the comment was that the phosphorus is mostly in the soil already.
20:56
Bingo.
20:56
So just, you know, we always got to think about where all phosphorus losses are driven dominantly by legacy phosphorus that’s accumulated in the soil over many decades, right?
21:08
And so what we do any particular year, it does matter, right?
21:10
It can have important impacts, especially if we get unlucky with with respect to weather events.
21:16
But really and for many of our systems, it’s controlling that phosphorus pool that’s built up in the soil that has maybe stronger short term leverage.
21:27
But again, right, there’s always exceptions, right?
21:29
You ask Extension, we say, well, it depends, right?
21:32
You know, it really depends like if you get unlucky with, you know, precipitation or frost right after application, right, where some of that newly applied phosphorus might be vulnerable to these large transport events.
21:46
This this situation could be different in some years, especially, right, if you’re a small dairy and you have to make a, a winter application of manure.
21:54
Absolutely those, you know, those differences in in phosphorus application can matter.
21:59
But if we look at sort of big picture long term weather, you know, the big lever in the system is the phosphorus that’s built up over many years.
22:09
And so we can look at that more clearly when we look at how the Phosphorus Index varies across these soils that differ in their soil test phosphorus.
22:18
So if we could wave a magic wand and take a soil with 100 PPM, bring it down to 50 or even 25, right, we see really clear reductions, right?
22:29
And so if you’re able to decrease your phosphorus inputs on these high soil test, you know, soils over the long term, right, that is going to have a really important impact.
22:39
And so Chris will will tell you how how low can you go and still, you know, have have a good have a good crop that’ll be coming up next.
22:48
OK.
22:49
So for until now we’ve talked about this one soil type in Northeast.
22:54
Now we’re going to expand and consider, you know, some variation in these soil types.
23:00
So we’re going to look at the Hortonville, the Kewaunee and the Manawa silt loam.
23:04
So differences, subtle differences in in slopes and physical characteristics of these soils.
23:12
We’ll see how important that is.
23:15
So again, just like I showed you for the Manawa, now we’ve got the Hortonville and the Kewaunee.
23:22
These are our baseline scenarios, chiseled disk, no cover crop.
23:27
And what you see is that these P Index values vary a little bit.
23:32
We’ve got, you know, we’ve got a couple of soils up near, near 4.
23:36
We’ve got one that’s even lower down here at at 2.
23:41
And so I’m, I’m curious if anyone has a guess, right.
23:44
Why is this Manawa silt loam generally lower right, almost half the P Index for these baseline scenarios.
23:53
Anyone got a sense of what’s, what’s driving that?
23:56
And the answer is in the title, I guess of these.
23:59
Yeah, yes, please.
24:01
Yes, the, the, the response was slope absolutely right.
24:04
We’re dealing on these flat, flat grounds, right?
24:07
We just have less inherent vulnerability to P loss and that’s what’s bringing these baseline scenarios down.
24:16
OK, so now what I’ll do is walk you through these same conservation practices that we looked at for one soil and see how this how this varies right across these different soil types, right?
24:29
So these are our baseline chiseled disc scenarios.
24:32
And then moving with this gradient of decreasing tillage intensity across all of these soils, right?
24:39
And so we can ask the question, well, which soils are benefiting the most from decreased tillage intensity?
24:46
Well, in general, it’s going to be these soils that are starting off with higher values, right, By the time we get down to strip till or no till, right.
24:53
We’ve brought down the Hortonville and Kewaunee quite a bit, right.
24:58
And so even though the Manawa is starting off at higher levels, we’re get or at lower levels, we’re getting more reduction in P losses from these from these more steeply sloped soils, a similar sort of result with the cover crops, right?
25:15
As we saw before, we’re not getting a heck of a lot of benefit in, in this, in this scenario from the October drill or the September drill, more P reduction from that August arial seeded rye, if you were able to do that as a producer.
25:34
And again, we sort of hit hit on this before, right?
25:37
In some of these scenarios, the P index creeps up slightly with that October drill simply due to that disturbance, right?
25:45
That increased disturbance may be outpacing on the growth of cover crops that we might have.
25:51
But again, this is a long term average, right?
25:55
If we have a warm year and that cover crop is going gangbusters or if you had a high seeding rate, you could overcome some of that disturbance.
26:02
Yes, yes, please.
26:04
Yeah, bingo.
26:05
And so the question is, is there anything else that’s burying in these scenarios that is it just the cover crop?
26:10
That’s exactly right.
26:11
And these differences, everything else is held constant, but we’re adding this cover crop.
26:17
So that’s, that’s a great question.
26:18
And so to emphasize, we had, you know, over 100,000 scenarios that Hava’s team ran.
26:25
And so we also looked at all of the combinations.
26:27
There’s some really interesting stuff when you start looking into the interactions.
26:31
Just to keep things simple and manageable, we’re looking at changes in one particular practice here today, OK, filter strips, right?
26:41
As just as we discussed before, a lot of P reduction benefit from adding that filter strip, especially when we’re looking at the more, the more vulnerable soils, not as much of a benefit from the Manawa silt loam because we were pretty low to start with begin adding winter wheat is, is, is pretty, pretty beneficial, but more so in those more vulnerable soil classes.
27:07
OK.
27:07
And so, OK, so we’re looking at raw P Index values before here, I want to show you the, the change in the P Index, right?
27:17
So looking at sort of treatment versus control, how do these practices stack out against each other, right?
27:24
So here’s 0 would be no change in the P index and a negative number would be a decrease, right?
27:32
It’s what we’re what we’re looking for.
27:34
And so each one of these boxes is going to be these different current categories of practices that I’ve been walking you through, through over the past slides.
27:43
And so, so what we see I think is, is, is pretty encouraging when we look at these different categories of conservation practices.
27:51
We can get some fairly substantial reductions in P Index by thinking about decreasing our tillage intensity by planting a cover crop, especially if we can get it on early by adding a filter strip or potentially by adding an overwintering perennial into a rotation.
28:09
In many cases, we’re able to shave off several pounds per acre in these P Index values and again more so when we’re thinking about these more vulnerable soils in terms of their phosphorus losses.
28:22
So it’s sort of, you know, choose your own adventure right.
28:25
If you’re thinking about a new a new practice, any single one of these practices could have a really substantial impact at the at the field scale.
28:36
What’s what’s interesting I think is to put these four practices, so tillage, cover crop, filter-strip and rotation.
28:44
We can contrast these with a few of the other factors that we evaluated in these comparisons, right?
28:51
We had our differences in soil test phosphorus.
28:54
So again, sort of waving the magic wand and saying what if you could start, if you could bring these these levels down instantaneously, what would your benefit be?
29:04
We do see some benefit, although it tends to be a little bit smaller than some of these practices that are really decreasing soil loss, nutrient form.
29:15
If we’re looking at manure versus fertilizer, not much of a change overall.
29:19
In some cases, we’re getting a benefit from adding manure simply because we’re adding some organic matter, right?
29:25
That’s potentially help helping us with soil aggregation and soil characteristics, a nutrient rate, you know a small sort of instantaneous change and then again nutrient timing, spring versus fall.
29:41
When you look at all of the other factors that are varying, that doesn’t turn out to have so much leverage sort of looking at these long term average P Index values.
29:53
OK, so now we’ve, you know, until now we’ve focused on the East Central regions and now we’re going to expand and look at these same kinds of systems implemented across the whole state.
30:03
So again, just to emphasize, all of these systems are managed the same.
30:08
What’s allowed to vary are the crop yields and the nutrient removal and the, and the climate, right?
30:15
You know, certainly the climate is varying dramatically across these regions, but all of these other management characteristics are staying the same.
30:23
And so now you’re seeing these colored box plots.
30:26
So each one of these colors represents a different agricultural statistics district in, in the state.
30:33
And so the East Central is down here and sort of this purplish color and, and what you see right, in the context of the overall statewide values, these soils are sort of intrinsically low in terms of their vulnerability to P loss, generally flatter, less, less erosion potential.
30:53
You know, meanwhile, right, if we’re, if we’re moving over to the western part of the state into the driftless, these sort of West Central and SW soils, many of these dominant soils are much more vulnerable to erosion.
31:06
And, and I want to, you know, make the point here that these are sort of worst case scenarios in that one of the assumptions of the Russell 2 model, the way this is implemented is that tillage is 90° to the contour, right?
31:21
We know that that sort of worst case scenario in many cases folks are not doing this especially on these steep slopes.
31:28
But it’s sort of again kind of one sort of way to bound this end member so that anything that we do is likely to really bring this down.
31:38
And we know in practice these are likely to be overestimating the actual loss values from these scenarios.
31:45
OK, So East Central, right, you all have sort of lower intrinsic vulnerability.
31:52
The central at central sands, right, is, is the least vulnerable of all, right, because we have flat soils, sandy, lots of infiltration, very difficult to generate runoff even if we have soils with high soil test values.
32:08
So, right, it’s really important to consider these, you know, overall differences in the susceptibility of soils to erosion as well as the climate differences among these different regions in our state.
32:21
So now again, like we did before, we’re going to start looking at differences in conservation practices.
32:28
So again, on the left, we’ve got our chiseled disc scenarios, you know, tremendous variation.
32:33
But as we start backing off tillage intensity, you can see the overarching theme across all of these soils and regions, right?
32:42
Are these systematic decreases in phosphorus losses, especially, especially with the strip till and the no till.
32:49
And so many of these scenarios, right, where we’d be well above 6 and sort of our business as usual tillage simply by backing off a little bit, you would now be in compliance with your nutrient management plans for many of these, many of these systems, a rye cover crop again, a lot of variability among regions.
33:12
One interesting feature that I’ll point out as we start to move to the South, we do see some situations where we can begin to get some benefits from the October and this especially the September drilled rye, right, just getting some more growing degree days, getting some more biomass accumulation in the fall, we can start moving the needle.
33:33
And so really that that context matters.
33:35
The more biomass mass that you can get, the better, the better the impact is likely to be.
33:41
But again, sort of the winner, right, moving into the future, the more we can think about opportunities for getting those cover crops on early, it’s going to have more of a disproportionate reduction for phosphorus losses.
33:55
OK, filter strips again, highly effective across all of these different systems even for these most vulnerable kinds of operations, right?
34:05
We’re able to bring the P Index down well below 5.
34:10
So I think, you know, filter strips really deserve some consideration, especially in these challenging economic times, right?
34:17
If there are, you know, maybe low yielding areas that are sort of, you know, marginal next to to streams, especially if you can pick up some cost share for establishing that filter strip, but maybe a win-win kind of a situation.
34:32
Winter wheat, right.
34:33
Again adding that overwintering perennial has a lot of benefit for the overall rotation average.
34:41
And so we’re seeing that that benefit across all of our scenarios, often times reducing the P Index by half.
34:48
I’ll note that I’m focusing here on corn grain, soybean.
34:51
We see similar kinds of trends when we compare corn silage systems without alfalfa versus with alfalfa.
34:59
Sort of the overall magnitude of decrease is pretty similar for those systems as well.
35:06
And so finally, as I showed you before, we can look at sort of these absolute decreases in the P index across these categories.
35:14
And the good news is, right, you know, whether we want to think about decreasing tillage, adding a cover crop especially early or adding a filter strip or maybe thinking about perennials in the rotation, we can get these really substantial decreases in our Phosphorus Index.
35:30
And at the end of the day, right, it’s that absolute pounds per acre reduction that’s really key, you know, in terms of thinking about decreasing these algal blooms over the over the medium and long term.
35:43
So I guess the really the take home points is that really we can get benefit by focusing on our most vulnerable soils first, right.
35:50
You saw that in those last figures, those large reductions when we think about reducing P losses from those erosion sensitive soils.
36:00
There’s a number of practices that can help us do this.
36:03
And simply adding one of these practices can really move the needle.
36:07
Adding more is great too, right?
36:09
You get some redundancy, but those marginal benefits often times will begin to tail off.
36:14
And so finally, just I’d love to discuss this if if folks are interested in this project and you know, can help provide feedback as to how we can improve the presentation or if there are specific practices or combinations of practices that are interesting to you, we’d love to hear this.
36:31
We’re hoping to finalize all of this information in a report by the sort of middle early, early next spring.
36:38
So ultimately this, you know, this information is going to be accessible and hopefully will be be useful to you all and sort of thinking about the big picture.
36:48
So hopefully we have time for more questions if people have them.
36:51
I don’t know how we’re doing on time.
36:54
Great.
36:55
So please, what, what, what would you all like to talk about?
36:58
Yes, Sir.
36:59
Great question.
37:00
So the question was for the winter wheat addition, are we taking off the straw in these scenarios?
37:05
We were leaving the straw and that’s it.
37:07
That’s a great point because that residue does have leverage on the results.
37:12
I think we could certainly do the scenarios with straw removal in the future as well.
37:17
I would sort of predict, yes, the P Index is going to creep up a little bit, but we’re still going to have that substantial benefit of green cover during the during the spring period
37:27
Yeah, great question.
37:28
What else that, that’s a fantastic question.
37:32
So, so we, we tended to be fairly conservative with the determination time in these scenarios, but that would be another lever that we could start pulling.
37:41
Is, is, is running the scenarios with variation in termination right, even up maybe the planting green.
37:47
And so we tried to keep this, this manageable.
37:50
Of course, it begins to spiral out of control.
37:52
We’ve got 100 over 100,000 scenarios already.
37:55
But I think now that sort of got a workflow down, I’d love to explore that, that sort of question in the future, right?
38:01
All else equal, yes, extending that termination time is, is going to help.
38:07
Yes, please.
38:09
Ah, great question.
38:10
And that’s also the question was, is any of this tied to yield?
38:14
So for all of these scenarios, we’re essentially we’re fixing yield as a as a constant, but, but that’s certainly true, right?
38:22
You know, there is evidence of potential yield drag from cover crops depending on how they’re being managed.
38:29
So that’s definitely another trade off to consider.
38:32
Yep, yes, please.
38:37
Yeah.
38:37
So the comment was could you take a sort of a, you know, worst case corn silage scenario with, you know, no, no cover aggressive tillage and stack conservation practices and look at the decrease.
38:49
And yes, we actually have those have those data and and the results are are pretty, pretty dramatic, right.
38:54
For most of these systems, if you stack practices, you could get pretty much all of them well, well below 6, if not not much lower.
39:03
And I think one of the the interesting points that emerge is that it’s often time the first sort of conservation practice that has the largest marginal benefit, right?
39:14
So, you know, simply by backing off on on tillage or adding a cover crop or a filter strip, we get that largest initial decrease.
39:22
But yes, you can definitely go lower if you keep stacking them up.
39:26
And so part of what we’re doing is sort of using some some statistics to look at those combinations that are sort of most, most effective.
39:35
And if folks are coming to the, the, the Agri-Business Classic, I’ll be diving into sort of that more comprehensive story and that will also be in the report that’ll come out this spring.
39:44
So great, great point.
39:46
Thank you for that.
39:49
What else, anything else?
39:54
Well, if not, I’ll be around all day and happy to happy to chat, chat with folks offline or my e-mail is, is here for the folks on Zoom if they want to send me a note.
40:02
Happy to happy to do it.
2026 Updates to Wisconsin P and K Soil Test Interpretations and Rate Recommendations
Chris Bandura, conservation cropping outreach specialist, UW–Madison
Dr. Matt Ruark, professor and extension specialist, UW–Madison Department of Soil and Environmental Sciences
Chris Bandura, conservation cropping outreach specialist, and Dr. Matt Ruark, professor and extension soil fertility and nutrient management specialist, UW–Madison, provide an overview of upcoming 2026 updates to Wisconsin’s phosphorus (P) and potassium (K) soil test interpretations and fertilizer recommendations for corn and soybean grain systems. Learn about the research behind these changes, including multi-year field trials, updated critical soil test ranges, and revised nutrient removal coefficients. The session also explains how these updates will affect rate recommendations, interpretation categories, and nutrient management planning tools like A2809 and SnapPlus. Discover practical insights for optimizing ROI and managing soil fertility under changing economic and agronomic conditions.
Transcript
0:05
Good morning, everybody.
0:06
As the the slide here suggests, we are going to talk about some updates to P&K Soil test interpretation and subsequent fertilizer rate recommendations for corn and soybean grain systems foreshadowing it says 2026.
0:21
So sometime next year is when this will come out and we’ll talk more about that in a little bit.
0:28
All right.
0:28
So our game plan today is we are going to just provide you kind of a brief overview on the philosophy that is has been used in the state and will continue using in the state when it comes to making P&K rate recommendations.
0:43
We’ll give you a little overview on some field research that was done briefly, kind of go through the study design of that where it was all done, and then we’re going to talk about the approach that is currently being taken to update these soil test interpretations and rate recommendations.
1:01
I apologize, that looks pretty blurry, at least here in person.
1:05
But again, just an overview of the philosophy here.
1:08
So along the bottom horizontal axis you’ve got soil test category.
1:13
We’re going from what we’re calling very low through excessively high.
1:17
We’ll define those a little bit later.
1:19
On the Y axis vertical, you have nutrient recommendation.
1:23
So the the trend here is that as soil test levels go up, the amount of nutrient being recommended should go down.
1:31
There’s three distinct zones on this figure you see build up, maintain and draw down running along the top.
1:39
So what we mean by that is if our soil test is what we call optimum, our goal is to maintain that soil test level.
1:48
And so we are going to fertilize, recommend fertilize rates that meet expected crop removal.
1:55
The assumption there is that if we apply what the crop is removing or what we think the crop is removing, our soil test levels won’t change very much.
2:05
On the right hand side of that is what we call draw down.
2:08
So if we are testing high, very high or excessively high, our objective is to slowly draw that soil test level down into that optimum range.
2:17
So we apply rates that are half, one quarter or zero of crop removal on the left hand side of optimum you have build up.
2:26
So if we’re testing the sub optimally, our objective is to not only apply the nutrients that crop needs this year, but also applying extra nutrient to slowly build those test levels up over time.
2:41
All right, So that’s just kind of setting the stage here.
2:44
On the right, you’ll see a map.
2:46
This is 6 different research locations.
2:49
So Doctor John Jones, let’s take a minute to give some shout outs here.
2:53
Prior to him going to University of Illinois, he initiated this P&K rate response work at all of these locations and actually from afar.
3:03
He is still managing the final year of data collection.
3:07
Those will all wrap up this year.
3:09
Number of other people at at the UW that are also working on this data set.
3:14
Doctors Matt Ruark, Natasha Rayne, Francisco Arriaga, Chris Clark and Kevin Jarek both in the room as well.
3:21
So lots of people working on this, but John is the one that implemented this research.
3:26
And So what you’ve got, what we’re going to show today is data from 21 through 24 at each location.
3:33
And every year we had both corn and soybean grain being produced.
3:40
Just to throw that out there, we have no manure and no cover crop ahead of the corn or soybeans in any given year.
3:47
No till and traditional tillage utilized, just depending on which site you’re at, big range in soil, soil characteristics across those six locations.
3:59
The common thread between the locations though is they all started with pretty low soil fertility, meaning P&K.
4:06
Some of the locations had single digit phosphorus soil test numbers, low double digit soil test K numbers.
4:13
So starting off very low, meaning that they are very responsive sites.
4:18
Theoretically they should respond to fertilizer quite well.
4:21
And so in 2021 when these were started in the first year of the study on those low testing soils, they we, John and his team implemented what we call a full factorial of P&K application rates and all that.
4:38
It’s just a fancy way of saying all possible combinations of different rates of P&K including zero P and K.
4:47
So the goal was apply a whole bunch of different rates of P&K to establish a gradient or a range and soil test levels on each location and replicate that time and time again.
5:01
So we wanted to have very low, low all the way through excessively high testing fields at each location.
5:10
All right, so diving in, this is the approach that was taken for identifying what we call the critical concentrations or in other words, the optimum range.
5:22
What was done is you have two different statistical models that were fit to the relationship that you see here behind me.
5:29
You have soil test phosphorus on the X.
5:33
And just to clarify, all the soil test information we’re looking at today is Bray one.
5:39
There will be no data talked about today regarding other extraction methods like Malek 3 for P&K or ammonium acetate for K It’s all Bray 1.
5:49
So that’s on the X axis.
5:50
And then you have relative grain yield on the Y.
5:53
And what relative grain yield means it’s the average yield where no P or K was applied divided by the average yield where yield was maximized, the rates where yield was maximized.
6:06
So it’s a, a relative scale allows us to kind of normalize yield across locations and across soil test levels.
6:14
And So what we do here, you’ll see in the the red dashed line is we fit what’s called a linear plateau model where relative yield increases linearly with increasing soil test P up to a certain point before it flattens off, it hits that plateau.
6:31
And then we also do that with that black line.
6:34
You see it’s called a quadratic plateau.
6:36
It’s just a slightly lower rate of increase, lower rate of change model.
6:41
And what you’ll notice is that there’s a little bit of a space between where that red model plateaus and where the black model plateaus.
6:49
And so that range by doing this approach here, that range is what we call the optimum range.
6:55
It’s the, it’s that that range between this more conservative model, the linear model and a little bit more of a liberal model being that quadratic plateau model.
7:06
Does that make sense to anyone?
7:08
Any, any questions on on that at this point in time?
7:13
All right.
7:13
It is not the only way to identify critical or critical concentrations.
7:18
Just to throw it out there, what some other states do is they say, oh, they’re going to pick a number out of a hat.
7:25
A lot of times it’s based on a research hat, but it’s a hat nonetheless where they’re going to say we’re going to set our critical concentration to be that where relative yield is 95%.
7:35
So what they can do fit this statistical model here, go to where you know, we have relative yield 95% draw the line down and that becomes your critical concentration.
7:46
So that’s just another way of thinking about how this is done out there.
7:51
All right, so this is all of the the soil test P data.
7:55
This is again from 21 through 24.
7:58
You have our loamy group soils as the left panel and the sandy group soils on the right panel.
8:05
How those are defined is spelled out in A2809.
8:09
So we’re still operating under those same definitions of what’s loamy, what’s sandy.
8:14
But yeah, you can see for both Loamy and Sandy, we have that optimum range with the O above the 2 lines.
8:21
And then you’ll notice a lot of other vertical lines on here where we’re delineating very low from low and then high from optimum and so on and so forth.
8:29
We’re dropping all these other lines on there.
8:32
And that’s some other black box statistics that are utilized to decide, you know, where, where is relative yield different, what to soil test levels are differentiating relative yield.
8:45
And so that’s kind of what it looks like.
8:47
And you’ll notice there, there is a fair bit of variation in this data.
8:53
The phosphorus data is a little bit more variable than the K data according to John Jones, who’s looked at this from several different states.
9:01
That seems to be a common thread, but none the less, right, that relationship is there generally as our solar test P increases, relative yield also does before it reaches a plateau.
9:14
So back to defining, what does it mean to be optimum or low or pick whichever one of those categories you want.
9:22
Historically, those are based on a a probability of response definition.
9:28
So for example, in the optimum category, what we’re saying is that that means a crop would respond to additional P or K fertilizer 30 to 60% of the time.
9:41
When we’re very low, it’s greater than 90% of the time that that crop would respond to additional P&K.
9:48
So it’s all about probabilities of response.
9:50
That’s what it means to be any of these individual categories.
9:55
You’ll note that these probabilities, these definitions, if you will, are also in the current UW A2809 documentation.
10:05
We follow the same textbook definition, if you will, as what was pulled out of this old soil fertility textbook.
10:12
So looking at reality, right, kind of ignoring theoretical textbooks for a minute, looking in this data set, look again within each of the soil test categories for soil test P, we looked at the average probability that that that a site responded to additional phosphorus.
10:31
And what you’ll notice is that all of these numbers on this figure on the right kind of line up really nicely with those textbook definitions.
10:39
So nothing really surprising here in your optimum, optimum category here with this updated research, we’re seeing about a 44% probability of response down to a 3% probability of response when we are excessively high.
10:55
OK.
10:56
And so here’s kind of the big summary.
10:58
This is what is changing in terms of soil test P interpretation, kind of the big take home for phosphorus here.
11:05
So what you’ll have, you have your loamy soils up on the top part of the table, Sandy’s on the bottom.
11:12
You see the 2012 row, that’s what’s currently in a A2809 and then the bolded row that says 2026, that that is the new range is based on this data set.
11:24
Long story short, for both loamy and sandy soils, it’s a very minor change in where these interpretation ranges are being set right.
11:34
Our optimum, our optimum for loamy soils shifted up one part per million.
11:40
Maybe more notably or more notable on that is that that range is now a 7 part per million window, whereas historically it was only a four part per million window.
11:51
So we have a bigger bullseye to hit, little easier target to hit now, but largely right, everything else just very, very minor changes.
12:00
And so one of the things that we wanted to do, we did we’ll do this for potassium too.
12:05
But is say, OK, here’s all these new ranges, here’s why we have these new ranges, show you all, all this data.
12:11
One of the questions we anticipated was, well, what should I expect, right?
12:15
Whether I’m a farmer, a crop consultant, someone at the county, what, what should I expect?
12:21
I have all these fields, I have soil test information.
12:24
How are the interpretations going to change on the, on the fields that I manage?
12:29
So what we did was worked with the the Snap Plus team.
12:32
Actually they sent us a little over a million soul samples that were tested by DATCP certified labs between 2012 and 2015, completely anonymous.
12:43
We had no idea whose data was was whose.
12:46
It was just rows and columns of data.
12:49
We.
12:50
So what we did was the Gray bars here.
12:53
This is representing the 2012 interpretation guidelines.
12:58
So for any given sample, we looked at what was the soul test P level, how would that have been interpreted based on 2012 guidelines?
13:07
The red bar is how would that same sample, that same soil test value be interpreted under these new, what we’re calling 2026 guidelines.
13:17
And so generally what you’re seeing is a is a slight increase in the percentage of samples that would now be considered low or very low, whereas last year, I guess right now they would be considered lower optimum.
13:31
Everything kind of those samples here just shifted down a little bit in their interpretation.
13:37
Again because of that widening of that optimum range, it went from 4 PPM to 7 PPM wide optimum range.
13:45
You see it a pretty good uptick in the number of samples that would now be considered optimum and then a slight reduction in those testing high or excessively high.
13:55
So again, small changes to where these ranges are being set, expecting more samples to test low or optimum.
14:04
So this is kind of the end of the phosphorus soul test section.
14:08
Any questions before we move on to K?
14:11
It’s a little more exciting when we get to potassium.
14:15
Yeah.
14:16
The question is, wouldn’t those P levels be skewed towards dairies and what dairy and nutrient management plans, these ones right here?
14:28
Yeah, I mean, sure, they could be.
14:30
I guess at the end of the day, whether they’re from a dairy or they’re from a row crop environment that just has high legacy P, it, it doesn’t necessarily matter really what that management is, right.
14:43
So I’ll test P is what it is.
14:45
And so and then and this data set, this response data that we looked at is what it is.
14:52
You could argue that that maybe if the the P being applied in this research was was from manure instead of from fertilizer, maybe we’d expect something different.
15:01
Stevens data, just looking at the P index, there wasn’t a lot of difference on that kind of analysis whether it was fertilizer or manure.
15:09
But, but certainly there’s maybe some Gray area there.
15:12
But P is P, Yeah, that’s a really good question.
15:18
And I don’t know how to I’ll, I’ll speculate.
15:21
How about that?
15:23
So I used to work at a lab.
15:25
And so when I started in 2018, I’ll say definitely less than half of the samples that we took in where I was at didn’t come in with some kind of a barcode or where you knew they were Geo referenced.
15:38
The trend I would say by the time I got out was the majority of samples were, I don’t know what that number is, but you know, there’s certainly a lot more sampling being done with some kind of a precision AG based platform doing VRT type things on the back end moving forward.
15:57
So I think the trend has increased, but I don’t know.
16:02
Yeah.
16:02
And I, I think the, the comment was if, if we had Geo reference data, looking at the, the percentage of samples that are in this excessively high, 52% of the data that we looked at was considered excessively high.
16:16
Are those also in line with impaired waterways?
16:19
And can we essentially that’s the low hanging fruit for where to go and, and spend our efforts on trying to reduce P levels and certainly P runoff and and things like that.
16:28
I think that that would be a whole nother effort even just aside from talking soul test interpretation.
16:33
But I think that’s a great idea.
16:35
Someone should probably look at that.
16:36
Yeah.
16:42
That’s also so that got asked on Tuesday when we were over in Eau Claire County.
16:47
I don’t know if John Jones has looked at that, if any of these relationships correlate back to pH in some way.
16:56
What we do know is that, right, the relationship between certain soil test methods is very dependent on the pH of the soil.
17:04
But I don’t know the direct answer to that question.
17:07
There’s likely something there based on the fact that it never really made the cut to be in these types of talks that John Jones has given on this.
17:16
My assumption it was relatively minor effect.
17:19
But yeah, it’s also interesting, you know what we what we know too about the Bray test specifically on a really high calcareous soils, sometimes we might not extract as much P that is actually there.
17:34
You know that extracting is going to be neutralized, P will precipitate out, won’t be able to be measured.
17:38
So some of them that were, you know, some of these excessively high numbers, who knows if if the absolute number was as high as it really is or not, but you know, either way considered excessively high in the standpoint of crop response.
17:51
Yeah.
17:52
So all right, let’s let’s move on to K All right, soil test K correlation here.
17:59
So soil test K on the X, again, same relative yield calculation on the Y.
18:05
The same approach was taken to delineate that optimum range and all the other ranges again, loamy on the left, sandy on the right.
18:13
The the first thing to point out here is that this data set so far does not suggest that we should change the soil test interpretation ranges from what are what is currently in A2809, the 2012 version.
18:28
You’ll notice there’s a lot fewer data points on the sandy chart than the loamy chart, but nonetheless that we have no, no signal that says we should we shouldn’t make a change on sandy soils.
18:42
What you’re going to see in a minute though is, is we’re going to make some pretty substantial changes to compared to what’s currently on the books for the loamy side.
18:51
So we’ll come back to that in a minute.
18:52
Now back to these probabilities of crop response.
18:55
All right.
18:56
So we dropped those lines on, on the on the figure, we delineated what we said is low and high and so on.
19:02
How does that compare to those those textbook definitions of what that means to be very low, etcetera.
19:08
So in the very low, low and optimum category, the observed probabilities of of response line up really, really well.
19:17
When we get to high and very high things kind of it’s a head scratcher what what you’re looking at on screen for the very high and high.
19:25
Let’s start with high.
19:26
You still have a 45% chance essentially of seeing a crop response that to added K and in the very high category, you’re still seeing a 23% response to added K.
19:40
And so you know what, at first we sit there and it’s like, well, why, why do we even call those high and very high?
19:45
Then why not just have an extremely wide optimum range?
19:48
Because both of those numbers would probably fall into that definition.
19:53
We, we did try playing with that data to see if it, if that would actually help us understand anything better and it didn’t.
20:00
But there’s a few ways we can kind of, we can kind of talk through this.
20:03
So although we are still seeing a high probability of yield response there.
20:09
The thing to keep in mind is that the magnitude of that response is relatively low compared to when we’re suboptimal or, or, or testing suboptimally or optimally, right?
20:21
We might be getting 100 bushels of corn here by applying in a very low soil test environment and maybe we’re only getting 10/15/12 something along that that order when we’re in that high testing environment.
20:36
And what what we’ll also say is in soybean, that yield response, the size of that yield response is also lower than that in corn on a relative, relative basis.
20:46
So the good thing with managing K is that this is really all about ROI and managing risk.
20:52
And the risk is either lost yield by not applying K or enough K or just lost return because we didn’t need to apply the K and we did anyways.
21:01
So even when we’re calling this high and very high, right, with soil test P, we’re, we’re also thinking about that environmental factor of, of having too much phosphorus in the environment with K.
21:13
We, we have no known concerns about potassium, right?
21:16
So we don’t, we don’t have that same stigma, if you will, about applying potassium on a high testing potassium field.
21:24
All right, so here’s the changes for soil test K and like I said, the the changes are quite a bit larger.
21:30
For starters, our very low category moved up 10 PPM.
21:35
Look at our optimum that shifted up by 20 part per million.
21:38
So it used to be 101 to 130, now it’s 121 to to 150.
21:45
Even more interesting, you start looking at very high, let’s let’s focus there.
21:50
So that moved up 40 part per million compared to what’s on the books now.
21:55
That’s interesting because that’s still at that level when we’re considering a field or a soil to be very high in K, we’re still making AK2O application recommendation.
22:07
It’s a quarter-ish of crop removal and we’re going to be doing that now.
22:12
We’re making that recommendation on soils testing 40 PPM higher now than what we were before.
22:20
Also interestingly, the point where we’re saying don’t apply K anymore at all, where we hit that cut off of don’t apply anymore K is now 60 PPM higher than what it used to be.
22:33
And so if we stop for a minute, ask that question of who in the room has had a hard time maintaining K or building K on soils in this region following A2809.
22:46
If you want to raise your hand, feel free, right, There’s probably at least Yeah, OK, there we go.
22:52
Lots of hands went up on Tuesday is when we talked about this.
22:55
So one of the things, one of this might be one of the explanations for that our crops are responding on higher testing K than than what we may be thought before.
23:07
And that’s kind of what this data set is showing us here.
23:10
And then again, just to summarize, no changes happening to our sandy group soils.
23:17
Lastly, same thing looking at the some just real data from Wisconsin, no surprise here.
23:23
We’re going to see a lot more samples that were considered, you know, say optimum that will now be considered low.
23:31
They used to be considered low and now they’ll be considered very low.
23:34
The closer you were to the, you know, to the edges, the outsides of the ranges, the, the more likely that field interpretation is going to is going to shift reduction in the number being considered optimum and then not a lot of change up up on the top.
23:52
So this is kind of the end of the soil test part of this thing.
23:57
Again, just recapping up on the top table, those probabilities of response from this data set in the bottom has the updated ranges.
24:05
This is what I’ll go into A2809 SNAP plus the program that that the certified laboratories interface with to, to put things interpretations on your soul test reports.
24:18
And this is a good time to talk about what’s in that blue box on the bottom table, demand level 1.
24:23
So in Wisconsin, we make P&K interpretations and recommendations based on demand level, relative demand level.
24:33
There’s four of them, one through 4.
24:35
Corn and soybean grain are demand level 1 crops and they’re not alone there.
24:40
You’ll see that there’s Clover, small grains other than wheat, pastures, grasses, so on, so forth.
24:46
The assumption going into this was that those were all grouped before, again making the assumption that their relative demand for P&K was similar to that for corn and soybean.
24:58
We don’t have new field correlation and calibration data for these other crops.
25:03
We likely didn’t before either whenever the current recommendations were made, maybe a little bit here and a little bit there, certainly not like what we have for corn and soybean.
25:14
So moving forward, these updated ranges will also apply to those other demand Level 1 crops, not just corn, soybean, grain, but these other ones in that group too.
25:26
Yeah.
25:27
The question was with increasing K rates or maybe we should say the increasing frequency in situations where K might be applied, right.
25:35
The rates aren’t necessarily going up with just more potash might go on the landscape as a result of this.
25:41
Question is, do we have concerns about chloride toxicity?
25:45
At the moment we do not.
25:47
There’s been some work done in Minnesota relatively recently in in soybean specifically looking at how much chloride from from applying potassium can those soybean crops handle without seeing the yield reduction.
26:01
And it’s really high.
26:02
I don’t remember the number, but it’s like really, really high.
26:04
It certainly wasn’t anywhere close to where like our highest rate recommendation would be even on a very low high yield testing environment.
26:14
So again, the rates themselves, and actually the contrary is going to come up here in a few slides.
26:20
The the rates themselves are actually going to be decreasing a little bit.
26:24
It’s so spoiler alert, but it’s, it’s simply just the amount of ground where K might be recommended.
26:31
That’s what’s increasing.
26:33
Good question.
26:35
Anything else before we dive into the, the the recs themselves.
26:40
All right, so talking about how are these rate recommendations going to change?
26:47
The single biggest component of the recommendations are crop removal assumptions.
26:53
And So what you’ve got on screen here, the top 2 panels is corn P on the left, corn K on the right, soybean P&K on the bottom.
27:02
You’re looking at grain yield along the X axis from zero to 300.
27:07
And then you have grain removal in pounds per acre on the Y.
27:11
And you’ll notice relatively linear relationship between those things.
27:15
More yield means more nutrient removed.
27:17
That makes sense.
27:19
The one thing we want to focus on right here though is the variability in removal.
27:25
And so if we if we focus on K back to this question I asked who has struggled to maintain or build soil test K following current recommendations, this could be another reason for that.
27:39
So if you look at this 225 bushel per acre yield level on the corn K panel top right, there removal could range from somewheres around 20 to somewhere’s around 80, right?
27:52
There’s a big cloud of data there.
27:54
And depending on the assumption that we make in the recommendation system, the number we assign to what is K2O removal per bushel of corn grain is going to influence a lot on on the resulting recommended rates.
28:08
And so if your reality ends up being substantially different from what we select, that might explain why you’re not seeing on the ground in your soil test and your crop production what what we’re seeing here.
28:21
Yeah.
28:22
The question was what causes this variation and P&K removal.
28:26
Although we don’t know, we didn’t specifically try to quantify the sources of variation here.
28:32
We can assume that it’s going to be soil type, moisture status, season long precip variety certainly might have an effect on it.
28:42
There’s a number of things that influence nutrient removal and nutrient availability.
28:49
So it’s hard to know.
28:50
It’s most likely going to be soil moisture in the sense of K is is my assumption, but we didn’t measure the sources.
28:58
You have a question.
29:00
Sure.
29:00
So the the more vigorous the plant is, the longer throughout the season, the more nutrient ultimately it’s gonna gonna remove.
29:06
So season long plant health will have an effect on that too?
29:10
Yep.
29:11
All right, so let’s dive into what numbers are we going to use.
29:18
This is kind of the same data we just looked at, just being displayed a little bit differently on the left hand side.
29:24
We’ll focus on corn first.
29:27
Phosphorus is the left box.
29:29
Potassium is the right box.
29:32
Want to make a note that in this line of work, allegedly I I’ll say allegedly because I personally don’t know this data point.
29:38
I was told this by Doctor John Jones.
29:40
A common thing to do is to utilize the 75th percentile when it comes to picking a nutrient removal coefficient.
29:48
What does that mean?
29:50
This is that box and whisker plot that Steven showed us a bunch of earlier.
29:54
The top of that box is the 75th percentile.
29:57
What that means is 75% of observations were actually lower than that point and only 25% are are greater than that point.
30:06
So we’re kind of erring on the higher side of things, if you will.
30:10
And just to clarify to a nutrient removal coefficient that is the amount of nutrient per bushel of grain.
30:16
That’s that’s what we’re talking about right here.
30:19
So in this data set for phosphorus and corn .36 was the the measured 75th percentile.
30:28
What’s currently in A2809 is .38 for potassium, we measured .2 here and we are currently closer to .3 in A2809.
30:41
We are going to be reducing down to that .2 and we’ll talk about that about why right now looking at soybean again .84 for phosphorus removal, very similar to the current .79 in A2809 today.
30:59
We also have Shawn Conley, you might know him, the soybean specialist in the state.
31:04
He has a huge nutrient removal database too.
31:07
So we were able to compare the soybean data from this study to a lot of his work.
31:12
He had .74.
31:13
So all relatively close.
31:16
And again in in potassium, we see a 1.2 versus 1.4 in our current recommendations and Doctor Conley’s is 1.26.
31:26
So looking at at both corn and soybean, there’s a signal here that our current K removal coefficients are probably just a little bit too high.
31:36
We’re actually removing a little bit less K2O per bushel being produced than than what we were previously assuming.
31:44
So as such, the the K removal coefficients for both crops will be slightly reduced.
31:50
This kind of summarizes that change.
31:52
So again for corn, we’re not changing the P removal and we are slightly reducing the K removal.
32:00
And then for soybean, again slight increase in P and a little bit bigger decrease in K, OK.
32:07
So all that said, how are the actual rate recommendations going to change?
32:12
And so the biggest, the biggest single factor that will result in you seeing a different rate recommendation on the same ground with the same soil test next year versus right now is completely depends on how is that soil test value being interpreted.
32:29
That if if in the 2012 interpretations it was considered optimum and due to the shifts up in P&K interpretation, it’s now considered low by default, you will see a higher recommendation because remember, if we’re testing lower, not only meeting crop removal, we’re also trying to build so that, that rate is higher.
32:50
So that’s the first thing to consider.
32:53
I’m going to skip this.
32:54
When we look at now with those slightly reduced nutrient removal coefficients and potassium and that little bit of change we had in beans, we went through all the different soil test levels and all of the yield goals that are in A2809 today.
33:10
And we compared the current recs versus these new recs, right?
33:15
Again with those coefficients being adjusted on the average in corn, again, nothing is changing with P2O5 rate recommendations on average actual 12 lb/acre reduction in potash rates.
33:30
So going back to the, the question about more, you know, higher rates or more rates, right, we’re actually seeing slightly reduced rates.
33:38
The range is 1 to 23 LB reduction.
33:43
So the, the higher the yield level and the lower the current soil test value is, the more change you’re going to observe.
33:51
The higher your soil test is and or the lower your yield goal is, the less significant of a change you’ll observe.
34:00
And then for soybean rate, a zero to 3 LB per acre reduction in P rates and a 1 to 14 LB reduction in K2O rates.
34:13
Just want to throw this out there.
34:15
I’m not sure how how tied everyone is to the current tables that are in A2809.
34:20
There’s a ton of tables in there.
34:22
P&K rate recommendations are currently just in those ginormous tables where you got to draw lines from the side and the top and figure it out.
34:30
We’re also likely to publish just these very simple linear equations where, you know, depending on your crop, you pick a column, depending on the nutrient, you pick the table, right?
34:41
Then you look at where’s my current soul test category, Boom, there’s your equation.
34:45
Plug in your yield goal.
34:47
Here’s that removal coefficient while you have a rate.
34:51
So to kind of wrap this all up, we’re going to look at some some rate calibration work.
34:59
So what this is showing you for corn on the left, soybean on the right.
35:03
Let’s focus on corn first.
35:05
You have phosphorus application rate and corn grain yield on four different soil test levels of of peat.
35:14
And what you’ll notice is that regardless of how much P2O5 was applied on the very low testing ground, yield was always significantly lower than if we were testing low, optimum or high.
35:28
The take away here is that you, you can’t fertilize your way out of a very low testing environment in the short term.
35:36
The objective is to slowly again build that up, get yourself into that optimum range where you can, where your yield levels can be up here as the same as if you were testing high, right?
35:48
Same thing in soybean as we see in corn in potassium, same song and dance.
35:54
We can’t out fertilize, we can’t fertilize ourselves out of this very low testing ground.
35:59
Again, justifying trying to build up into optimum.
36:03
The other thing back to those probabilities of response.
36:06
So if you’ll look at this, this dotted circle line here, this is the very or sorry, this is the high testing soil test looking at corn response to applied K2O.
36:19
And you’ll see that generally here in this data, there is a a response, right?
36:24
There’s a small response there, but it’s to a very small amount of potash.
36:29
So even if that that’s concerning to you, where why are why are we seeing that that high probability of response in the high and very high category?
36:37
Keep in mind it’s to a relatively low rate, but we are still seeing that, that response.
36:45
So our timeline on kind of releasing this out into the world is gonna be sometime next summer.
36:52
We’ve talked with a few different groups of consultants and, and, and partners around the state to kind of figure out what would be an OK time, maybe a less bad time of year to make a change to this stuff.
37:03
And it it was June to August sometime next year and that’ll include these new ranges and updated recs and things like A2809 on the website, snap plus and the lab reports will all be updated.
37:16
Future work.
37:17
We do have a little bit of corn silage data coming out of this project.
37:21
It’s it’s not a lot far fewer site years than than for the grain, but we’ll continue looking at the corn silage data and kind of do a similar analysis.
37:31
Do interpretation ranges need to be looked at a little bit?
37:34
Are the removal coefficients way different from what we’re currently assuming they are?
37:39
So that’s in the works.
37:41
Also, there’s a few of us that are hoping to do a similar assessment in alfalfa.
37:46
We submitted a grant here a couple weeks ago where we’re going to start looking at alfalfa removal of nutrients across the state hopefully.
37:53
So fingers crossed on that.
37:56
Wrapping it up again, slight shift up in ranges, pretty pretty small reduction in in removal changes to on, on the soybean side of things, K is really the big thing that’s changing.
38:11
Again, managing K is all about managing ROI, no environmental concern there.
38:15
So again, using these soil tests to help us understand where do we need nutrient to get a profitable response versus where can we skip that nutrient application.
38:28
That’s the one thing we kind of wanted to end with today going into this next cropping system with this really wonky input to output ratio in terms of value on things, high input costs.
38:40
Where can we cut back based on this data on on a high and very high, very high in the case of potassium, but on the high side of things, you can certainly get by with a lower rate, right if you need.
38:55
If we need to cut back a little bit, do it on high or very high testing ground.
38:59
This data suggests again that I’ll go back a few slides here, right here.
39:04
Cutting back on low or very low testing ground is not being advised at all right now because we already in a low yield environment relative to those higher testing environments.
39:16
So cutting nutrients try if you’re if at all possible to just keep that to those high and very high testing environments.
39:24
So with that, that’s all I had prepared.
39:26
So if we’ve got time for questions, I’m I’m happy to do that and or take complaints.
39:32
Dr.
39:32
Matt Ruark isn’t with us today.
39:34
So I’ll take all those and make sure he gets them at the end here.
39:38
So thank you.
39:40
Yep, yeah.
39:42
And there’s a lot.
39:42
I’m just going to make an assumption given where you’re coming from, Scott, is that on pretty sandy ground dry few years?
39:49
Is that is that where we’re struggling the most or is this kind of just across the board?
39:54
OK, well, and and that that’s one reason why we’re hoping to be able to do this in alfalfa as well as it’s a it’s been a while.
40:04
So and then you the I don’t for those on Zoom that didn’t hear it, Scott Royce from the northeast part of the state was talking about folks having a hard time realizing economic responses in their Ford systems to applied K kind of regardless of soil test level.
40:19
So yeah, that’s one reason why we’re hoping to look at alfalfa and and and potassium.
40:24
The other thing we’re hearing with alfalfa and potassium is, is it removing more, more per ton of dry matter yield than what, than what we’re currently assigning being 60 lbs per acre.
40:36
So hopefully we can, we can look at alfalfa too.
40:40
The other note I want to say, unless there’s other questions, just cut me off.
40:43
But with, with potassium management, what we didn’t show today is the interaction between nitrogen response and corn based on soil test level, soil test K.
40:54
So we know that our end use efficiency and ultimately the, the, the response and the yield that we can observe from a given amount of N is reduced and we’re testing lower, very low on, on K.
41:06
So having higher optimum testing potassium is going to help us maximize what we’re getting out of the end that we’re paying for and applying as well.
41:16
So again, when the years of workout, when, when it makes sense economically, you know, don’t forget about K management that it’s a big deal out there.
41:25
So any other questions?
41:28
Yep.
41:30
I have no idea.
41:32
I can’t.
41:33
That’s a question that I can send back to Doctor Jones and see if if he’s played with with that at all.
41:40
I assume because you’re applying K and sulfur and we know that these crops that we’re talking about today would benefit from both of those nutrients under the right circumstances.
41:50
That yes.
41:52
Is that specific to potash and any other specific source of sulfur?
41:58
I don’t, I don’t know the answer to that, but that’s where my brain would go.
42:04
All right, well, thank you all very much.
42:07
There’s my contact information if you ever need to chat more.
42:09
Happy to talk.
Next Steps in Wisconsin Corn Production Systems
Dr. Harkirat Kaur, assistant professor and extension specialist, UW–Madison Department of Plant and Agroecosystem Sciences
Dr. Harkirat Kaur, assistant professor and extension corn agronomy specialist, UW–Madison, explores the future of corn production systems in Wisconsin, highlighting innovations, challenges, and research priorities. Topics include historical yield trends, evolving technologies, and the role of short-stature corn hybrids in improving standability, resource efficiency, and silage quality. Preliminary research results on short corn performance, nutrient management, and integration with forage systems are shared, along with insights from long-term corn hybrid trials. Learn how genetic advancements, precision agriculture, and biological products are shaping the next generation of corn production strategies.
Transcript
0:05
Thank you, Scott for a wonderful introduction and also a nice historical anecdote because I think that sets the stage for what we are going to talk about in next 25 to 30 minutes.
0:19
So when I like to tell this in a way that, you know, when I was trying to put this talk together, I was thinking about the title that I gave and like a couple of months ago and I was like, I want to be as close to the title as possible.
0:35
Because once we start seeing the data by the end of the growing season, we get excited and sometimes the titles don’t that we give like 2-3 months ago don’t really match on what we are talking.
0:47
So I really try staying close to this.
0:49
And when I was doing that, I was like, if we are looking at the next steps in con production, how about we start from, OK, how about we start all the way back about 100 years ago from now in 1920s and 30s.
1:05
And as I was like, you know, going through some data resources on Internet, I’ve realized that from about 1930 to now, the corn production has been revolutionized in a way that we have seen bushels per acre of corn grow by about 500%, which was like 30 bushels in 1930 to an average of 180 bushels per acre at this point.
1:34
And all this came through various phases of innovation in terms of genetics, technology, etcetera.
1:41
So for instance, the first one that we had where we saw the yield rigor, you know go beyond limits was when we had hybrid corn introduction into the systems.
1:53
It was introduced around 1930s with adoption being more popular in 1950s and so on.
2:01
This was further, you know, complemented by an amazing work of soil scientist who eventually designed fertilizer prescriptions, fertilizer regimes for the crops and for the fields.
2:14
And then we entered into the era of biotechnological evolution where we had Bt traits entered into our corn systems and we had inherent protections from insects diseases.
2:28
We had herbicide tolerance incorporated into the systems, which help the management of overall systems to be much more efficient and easier.
2:38
From there we moved ahead into precision agriculture where today we can actually design prescriptions for a very specific part of the field and by understanding how the soil and the plant history is behaving in that region.
2:55
So as I was looking through all these, I was really excited about this next thing, the next big thing that we are seeing in con production and that is short corn.
3:07
And I will be talking about some of the research that we are doing on short corn at UW and how this will eventually help us design management decisions and practices which are compatible with the grower’s systems across the state.
3:23
So in order to design any management practices for something that’s coming up, we need to acknowledge what are we facing currently?
3:34
What are our variables at this point?
3:36
Starting with obviously the major part, which is whether variability and weather has been, you know going in all the crazy directions.
3:47
If I say anecdotally from 2023 with a dry spring to a very wet fall and then the things flipped in 2024, then 25 where we had an, you know, exceptionally cooler June with slow corn growth and then awfully warm October, which was I think the 10th or the 12th warmest on the record.
4:14
So along with that we have variabilities in terms of input costs, which with markets doing all the things that they’re doing with, you know, values going up and down all of sudden and our prices not really improving much.
4:31
That also comes with more new genetics as we talked about, accompanied with some of other resources such as mechanized and automated innovations in terms of equipment, machinery, etcetera.
4:45
All this when combined with the new evolving digital agriculture in terms of AI integration, resources that provide information on growing degree units, you know, regular weather updates that might help us stay ahead of the curve.
5:07
So when we look at all these variables in the current scenario, there’s one thing that I think about a grower when they are entering into corn production.
5:18
So today, if somebody is trying to get into corn production, they’re not looking at just one, one thing or one factor across.
5:27
They’re basically looking into a system, which means that if I put it simply in the context of today’s talk, they’re not just looking at a hybrid or a hybrid technology.
5:39
They are basically choosing a system because one decision will impact what else they are doing around it.
5:47
So, let’s move forward and look into the genetic innovation that we will be talking about today and that is short corn.
5:57
And if you are, if I hope you have had the chance to see a short corn plant in the field as of yet.
6:05
So it is genetically and selectively bred in order to have a reduced stature.
6:11
And that reduced stature is coming from reduced internodes and not, yeah, from reduced internodes.
6:22
And the the visible differences are very evident somewhere between VH to V10.
6:29
So for example, if you’re driving across a country Rd.
6:33
and you see a cornfield and if it is around the growth stage of V8 or V10, you’ll be most likely to tell which is short corn and which is tall.
6:44
If it is a little bit, you know, younger than that, say around V4 – V6, you will probably have to pull over and go in the field and see for the internode spaces between them to tell the difference.
6:58
So the other thing that we are seeing with short corn is obviously a ear which is closer to the ground and it comes with its own challenges which is something we are looking into as we move forward.
7:16
So why was short corn, you know, developed or what was the intent behind that?
7:22
Basically, the overall intended agronomic benefits for this was to actually improve standability.
7:29
So what we did in this, what the Breeders did, I would say more precisely, is that they reduced the stature of the plant, which lowered the overall center of gravity of the plant.
7:41
Which means that now if we have an event of a storm where we have strong winds or if we have strong torrential rains, the plant is more likely to be more stable and less likely to, you know, topple over and break into half, resulting in all the yield damages or the yield losses that we see.
8:05
So we are trying to offset lesser yield losses with when it comes to short corn.
8:11
Secondly, we are also hoping to have a higher nutrient and water use efficiency because we have a different plant line architecture, which means the distribution of the resources to the plant parts might be different and that will affect the overall resource use efficiency.
8:31
All this will also be accompanied by something which is very exciting for the industry and the growers as well.
8:38
And that is the easy accessibility because now the plants not a 7 or 8 feet tall and you can get into the field more easily for your fungicide applications eventually if need be.
8:54
So beyond the general agronomic benefits and goals, silage, sorry, short corn is being specifically targeted towards silage production as well, specifically for a state like Wisconsin and for a state where we take silage very seriously.
9:13
And because now we are having these conversations where BMR is being phased out, we are looking for alternatives where we can at least, if not achieve the same digestibility levels, at least have the digestibility which is somewhat comparable to those hybrids or better than the other tall conventional hybrids that we have.
9:37
And I’m very glad to tell you all that there are people in this room, Kevin, over there.
9:43
He’s working really hard to find alternatives in this direction both in terms of using the newer hybrids as well as the existing hybrids and the newer technology available with that.
9:56
So for the for silage intended benefits, the one thing that we really take very critically over here is the lower loss of foliage.
10:06
So a lot of us might know this, that when we want to have a higher quality silage, there’s always this conundrum of do we increase the harvest length because if sorry harvest height.
10:21
So, if we increase the harvest height, we are technically reducing the overall stock that is being fed into the harvester, but we’re also losing the number of leaves or the foliage that we are feeding into the system.
10:36
But with short corn, if you see over here, so this is a stalk of short corn and this is a stalk of tall corn.
10:43
And you can see that there are two internodes here, whereas there are three internodes here.
10:49
So basically we have a reduced stature of the plant, but we still have enough foliage intact where we can actually offset some of the yield losses by also enhancing the overall digestibility or quality, which means because we are having an overall lower lignin at this point.
11:13
Secondly, now because the plant is overall shorter, the ear forms a bigger part of the plant.
11:21
So that means the starch component of the plant is the higher percentage of the overall biomass, therefore increasing the overall digestible component of silage.
11:34
And this would eventually hopefully mean higher milk per ton and would amount to more stable quality and yield for our growers.
11:47
So in order to see if these claims or these intended benefits actually hold true in the field, we conducted some of the preliminary trials in the field and where we wanted to compare BMR hybrids, tall hybrids and short corn hybrids.
12:05
And here’s my wonderful technician, Derek.
12:07
He’s actually demonstrating how were the hybrids being different from tall to short.
12:15
And this year it was really interesting because we did get a good amount of rain in Arlington and we were seeing that both the short and tall corn, although different in terms of canopy architecture, the height differences were a feet or a feet and a half only, which was really exciting as well as I would say confusing sometimes.
12:40
However, when we were looking at the yield numbers, we did see obviously the tall corn had a higher yield number as compared to the both other types of hybrids, but the short corn yield was very much comparable to what we were seeing in tall corn.
12:57
Moving forward from there, if we were looking at nutritive values, we did see a higher starch content in short corn as opposed to BMR and it was very much comparable to tall corn.
13:10
But the one thing that I would like to focus here is that we did see a lot of variability in this data and that’s primarily because the intent behind these trials is to actually screen the germ plasm which is better for release in the commercial markets and also for the growers.
13:29
So hopefully in the coming years we’ll be able to screen some of those hybrids which are which are more variable and you know not providing us the intended results that we want to see.
13:44
Similarly, if we look at the digestibility in terms of NDF, we did obviously the BMRs were closer to 70. For
13:53
short corn, the values were although not as high as the BMRs, but it was very comparable to BMR.
14:00
And obviously we did see some of the hybrids which had the values on the lower side as well.
14:07
So again, reiterating that we are screening germplasm, we are screening the better hybrids as we move forward.
14:16
We also wanted to see how is this data behaving when we put it in comparison to dry yield and milk per ton.
14:25
So basically quantity and quality on the same chart in order to compare the results.
14:32
So our results show that most of the short corn hybrids that we tested fell into the quadrant where we have high tonnage, high quality numbers, which are favorable to what is mostly useful for the growers both in terms of economics and resources.
14:53
And it didn’t and we were saved mostly we were saved from falling into any of these quadrants where we have to compromise either between the quality or the quantity of the product that we are receiving.
15:07
So remember when I was starting this presentation, I was talking about system and not just one thing from the system.
15:17
So, because we want to see how this behaves in a system and since we are a dairy state, we work with forage systems, we wanted to see how would this behave in a system where we have other forage crops integrated with the short corn.
15:36
So, what we did was with the help of amazing colleagues at the Forage lab, we wanted to, you know, we wanted to conduct experiments where we compared tall and short corn hybrids in the systems where we have interceded alfalfa and also in the stand-alone systems.
15:55
We wanted to see how is corn behaving in those systems.
15:59
Today I’ll be talking about how short corn behaves from the same trial.
16:05
We will have data on alfalfa, which Dr. Kohmann will probably be sharing later in the extension season and you’ll get an insight on that as well.
16:18
So, when we were looking at these trials, we wanted to obviously first see how the canopy is changing for tall and short corn.
16:26
And we did see that the leaf area index was actually higher in short corn as compared to the tall corn.
16:34
And we did see a trend in the relative light intensity as well where it was lower in short corn as compared to tall corn, which is actually opposite from what we expected because short corn is being bred for more erect canopy and we thought we would receive more light on the ground, but our numbers are not showing that.
16:57
So, it’s a data from just one site, one site just one year.
17:03
So, we want to probably repeat this trial next year and see how things change with the in a different year and if there are some hybrid characteristics at play here or if it is just the overall behavior of the plant.
17:21
The other thing we were obviously interested in was to look for the yield values in both short and tall corn.
17:30
So, we did see that obviously the short hybrids had lower yields than the tall hybrids and we saw a lower yields in terms of interseeded alfalfa systems then the systems where we didn’t have any alfalfa.
17:44
But in order to put this in more context, we we kind of analyzed it in the relative terms.
17:52
So, if we see a tall hybrid con system with no alfalfa, which is practically the more conventional system or the more normal system that we see around us.
18:05
And if we consider that it is yielding at its 100% potential, for instance, if we introduce alfalfa into this system, we are getting a hit of about 9% yield from that.
18:20
But similarly if we have a short corn system with no alfalfa, number one, we are already we were seeing a 10% decline there, but introducing alfalfa into this system was only offsetting the yield by 3%.
18:38
So, which means that in a relativity, in a relativity term, a system of short corn is losing lesser yield when integrated with alfalfa or when we are interseeding alfalfa into it as opposed to the yield hit that we were getting in overall tall corn system.
19:01
So this is again I would reiterate our data, this is preliminary data.
19:04
We will be repeating these trials next year and the the data from that will actually either confirm or deny what we are seeing this year.
19:15
So moving forward, we also wanted to get a closer look on how the grain was behaving in these trials.
19:23
So, we collected some yield components in terms of the ears, in terms of the grain and these values have been adjusted to the moisture levels of 15.5%.
19:35
And here also it was interesting that the kernels per year were less were lower in shorter hybrids than taller ones.
19:44
However, the thousand kernel rate was higher in the shorter hybrids, which is something that brings back me to the to my question of overall starch accumulation and overall digestibility component of the silage values that we were seeing.
20:03
So, if there is an offsetting of a higher thousand kernel weight in or higher test weight in short corn, maybe we are seeing in a scenario where we have a higher milk per ton situation.
20:20
Looking at us, which is beneficial for for everybody, but that’s a big maybe at this point because I don’t have the data to support that.
20:29
We are still processing the silage quality data from this trial and we’ll hopefully be able to share that in some of the spring meetings this year as well.
20:41
So, when we were doing these trials for short corn silage, we had fortunately some hybrid seed around and we were like how about we plant it in a plot where we offset it with the three different levels of nitrogen?
20:59
Because the next question that is obviously going to come in the management of short corn is how do we manage it in the fields?
21:07
What would be the nitrogen management situation for these hybrids?
21:13
What will be the recommendation?
21:15
This is a preliminary data from this year, and we were actually surprised because the overall consensus was that we expected this trial, we expected short corn hybrids to perform better when we had lower levels of nitrogen.
21:35
However, it performed at par with the overall tall hybrids.
21:39
But as we move to the higher levels, it actually had higher yields as compared to the tall hybrids.
21:47
So, the treatments over here were applied in a way that we had 30 lbs applied at pre plant and the rest was a sidedress.
21:58
So these trials were conducted in Arlington.
22:02
We just had one location.
22:04
The soils in Arlington are also you know one of the best that you can find in this state.
22:10
So we’re not sure if that if these differences or these trends are coming from that we are repeating these trials with the with more treatments and more hybrids next year.
22:20
So hopefully we’ll have a better response curve and we will probably be staying ahead of the curve when these hybrids become available commercially.
22:30
So that you have understanding of how to manage nitrogen with that with these. The amazing colleagues at the soil science department will also be will hopefully be collaborating.
22:44
I talked to some of the amazing people yesterday and they were more than willing to do that.
22:48
So let’s see how that goes going forward.
22:52
So now because we are talking about short corn, grain silage, everything, there’s one other thing that I give so much credit to when it to the to Wisconsin growers and the growers across the Corn Belt when it comes to collaboration with research and data collection.
23:13
And that is the overall corn performance trials that all of you have been hosting for so many years.
23:21
So the next part of this presentation, I would just like to show and emphasize how we have been using those trials in in order to access the long term.
23:33
Yes, please.
23:38
So starting off with the first question that if were the populations the same for these trials, Yes, they were the same.
23:48
We do have another trial where we are looking at four different populations to see how the overall canopy structure and the competition behaves in short versus tall hybrids.
24:01
The second question was about row spacing, if we are better using narrow rows as in short corn.
24:09
So that is one of the questions issues that we have been trying to answer in our lab and considering we had certain planting constraints last year, we had to drop the idea of a row spacing trial.
24:22
Hopefully this year with the more pre planning we would be able to establish one of those and get a better answer for that.
24:30
So I don’t have an answer for this question, but we are looking into it.
24:33
The third, the third one, I’m sorry, I forgot.
24:41
So I would assume it should affect that.
24:45
It would be and it should be in a positive direction because the overall idea is to actually, you know, to increase the overall milk yields and also the total and digestible fiber as well.
25:02
So, yeah, I wouldn’t say so it’s, it’s primarily I think maybe because of the slope that we had in the field might be one of the reasons that we saw this difference.
25:19
But I, I, I don’t think that was the any disaster happening in that field.
25:25
So, so we have been looking at at least 5 hybrids in, in the trials where we are comparing it with BMR and tall hybrids.
25:37
For the, for the interseeding trial, we have two hybrids and then for this, this one we because it was like a last minute plant trial, we had only one hybrid for this one.
25:55
So also for companies, we just have Bayer at this point because we have been trying to reach out to other industry partners and they are not very keen to participate at this point.
26:08
We are in conversations.
26:09
Hopefully they want to enter the next year.
26:11
So, moving on to any other questions.
26:21
And yes, everything is at the same population.
26:29
I’m not displaying any data from population density trials today.
26:36
So I guess I would probably move on to the to showcasing what we’re doing with the corn hybrid performance trials and how we’re using the long term data available for us.
26:50
The primary goal for this small experiment, I would say a data modeling practice that we did was to create an overall map for United States relative maturity variability.
27:08
And the goal was to provide a fundamental resource or a starting point for a grower trying to enter into the corn production practice.
27:19
So, what we did was we collected data from last 25 years of corn performance trials across all these states.
27:29
Some of them have stopped doing these trials from last five to seven years because of various constraints.
27:35
But on average we could get data from about I would say if we were looking at 25 years, on average we had the data from about 15 to 18 years in each state, which gave us more than 15,000 points data points across.
27:56
So what we did was we wanted to separate how the planting date decisions vary across the state starting from the South to the North.
28:08
And these values were picked based on the hybrids which were which were yielding the most optimum yield considerations taken for that region.
28:20
Secondly, we coupled it with the overall growing season length from South to North.
28:27
If you look at this figure, it shows how season changes from South to growing season length changes from South to North where a variability of 365 days to 140 up in Northern Upper Peninsula and also Dakotas and Minnesota.
28:45
Here this is a simulation of an year where we had a late spring frost and we experienced a loss of days in the growing season length.
28:57
So all these variables when put together in terms of planting dates, growing season length, optimum yields across different hybrids across all these regions, we came to create this graph where we could actually generate or we could actually model the relative maturity values from South to North.
29:20
And we could we could actually figure out the variability that we were seeing starting from 118 here around down South to all the way to 70s up in the Dakotas and Minnesota, upper Minnesota.
29:37
So this figure basically is what is showing on glance how the relative maturity is varying from South to North when we are looking at corn hybrids and the most optimum yield levels that we are seeing.
29:53
This is one of the usage is one of the things that we could actually create from this amazing resource that we have cultivated across so many decades of, you know, repeated corn performance trials.
30:06
So next spring when and you get e-mail you know requesting your participation if you would be really interested in.
30:15
I just want to make sure that you know that the data we collect with the help of everybody is actually amounting to something more than just that corn book that is obviously very useful that we release every year as well.
30:30
So secondly, when we were doing all, we were doing this modelling exercise and, and putting together this map, we had people from across 5 different states who were corn agronomist, cropping systems agronomist contributing their data.
30:48
So as we moved from there, we thought how about if all this gets together formally and then we created this group of corn agronomists from across states of United States and we were really proud of the acronym that we came up with.
31:08
So the first project under this group that we are trying to do is actually a biological products evaluation in the corn production systems.
31:21
So if you scan this QR code, it will take you to the survey where we have listed all the biological products which are out in the not all I would say most of the products that are available in the market.
31:37
And what we want to do is gauge what are the top three to five more interested products for the growers are because there are so many things in the market and we can’t test obviously everything.
31:50
But if we can gauge an interest from the growers, those are the things we want to focus on.
31:57
This trial will be conducted in nine states starting in 2026 where we have this spatial and temporal variability to actually test how are these products actually performing in different types of soils and if they’re worth worth your investment or not.
32:19
Moving forward, I would like to, you know, end with the overall, overall conclusion from the preliminary results that we saw today where we did see that we have promise in the new innovations that we are seeing in the field and research.
32:42
But there is obviously need for more data.
32:45
There is obviously need for more, you know response validation in terms of short corn silage, in terms of short corn grain and nutrient uptake.
32:56
So we are going to expand on those trials next year with more extensive data collection with help from the students, researchers and extension educators.
33:06
Going forward, we are also looking to use the long term data, data sets that we have gathered across the state all these years in order to build tools which are actually and useful for the growers.
33:21
So that eventually we have a corn production system where we have an interaction of genetic innovation, automation tools, and which is supported by our long-term data that we have the access to.
33:38
I would like to end with the plug in these hybrid trials 2025 which went live Monday and these are hosted on Badger Crop Network and the Extension website.
33:52
These trials were conducted across 14 locations in Wisconsin.
33:57
in 2025. We received about 257 different entries for hybrids and we have the silage and grain trials in here we provide the the book also provides performance indices and those performance indices are not only dependent on the hybrid performance this year, but if that hybrid has been present over the years in these trials, we accumulate that data from previous years and then come to that number, which can help you decide on what hybrids to put in as we move forward.
34:34
And with that, I would just like to thank all these amazing people who have made this work possible.
34:41
And if there are any more questions on Zoom in the room, I would be, you know, happy to take them.
34:49
And these are my contacts, e-mail me, text me, call me.
34:54
I’m always happy to talk to everyone and receive the feedback, suggestions, questions, anything.
35:01
Thank you.
Forage Management for Success
Dr. Marta Kohmann, assistant professor and extension specialist, UW–Madison Department of Plant and Agroecosystem Sciences
Luana Queiroz, alfalfa outreach specialist, UW–Madison Extension
Dr. Marta Kohmann, assistant professor and extension forage systems specialist, and Luana Queiroz, alfalfa outreach specialist, UW–Madison, explore best practices for managing alfalfa and other forages to improve persistence, productivity, and nutrient efficiency. Topics include the role of potassium and sulfur in stress tolerance and winter survival, nutrient removal rates, and updated recommendations for alfalfa fertility. Marta Kohmann shares research findings on manure application timing and its impact on forage yield, nutrient balance, and soil fertility. Learn practical strategies for optimizing forage quality, managing nutrient exports, and addressing challenges like winterkill and traffic stress.
Transcript
0:05
Happy to be here and thank you all for being here as well.
0:08
I’m happy to share this spot with Marta.
0:11
So thank you Marta for letting me introduce a bit of of myself in here.
0:16
I am the Alfalfa outreach specialist.
0:18
My name is Luana Quieroz and just if technology allows, well, let me just click in here.
0:31
Let’s see.
0:33
No.
0:37
What about now?
0:41
OK, so here we go.
0:45
I am originally from Brazil, more specific from the northeast portion of Brazil characterized for a semi arid climate and then we go 8 to 9 months without a drop of rain, which was very sweet.
0:59
When I came to Florida, folks were talking about a two week drop.
1:02
So for me was very interesting to hear that and that’s basically what it looks like once we are on the drought season and then when we get some rain, as you can see, you can see some cactus here and they are very important for feeding livestock.
1:16
And where I’m from.
1:18
Just for a little perspective here, Doctor Kohman is also Marta is also from the South, from Brazil, but from the South region.
1:25
I was curious on how far our hometowns were from each other.
1:28
So turned out we were 2138 miles apart.
1:32
So quite different, but in many ways different in terms of the kind of livestock that we can have, the feeding, the strategies that we have to cope with.
1:41
So a bit of of everything.
1:47
I hold a bachelor’s degree in animal science, which I got in Brazil.
1:51
And I was able to work with extension ruminant nutrition and also research since my freshman years.
1:56
And since then I haven’t stopped.
1:58
And then I came to North Florida, quite different from where I was from.
2:03
And then I had the pleasure to work with alfalfa, which was very surprising for me as soon as I got to the United States.
2:11
It’s more detail about alfalfa in Florida that didn’t come back the following year.
2:16
We were trying to interseed alfalfa with C4 grasses.
2:19
For the first year it looked great as you can see in here, but the second year alfalfa didn’t want to pop up into that C4 grass mixture.
2:26
So here just a quick graph showing an average of two year and the proportion of alfalfa as we were moving into the hot months of the year.
2:39
OK, so I stayed in Florida, really liked it, worked with grass and legume mixtures for my master’s degree.
2:47
This legume that you see here is a warm season legume and in the pastures we have some that were planted in the 80s and the animals are still grazing on it.
2:55
That’s not the reality for alfalfa unfortunately, but I looked into some nitrogen dynamics across across North Central and South Florida project funded by NIFA, but also in association with the Cattlemen Association in Florida.
3:12
So it was very interesting, but always looking into that nitrogen credits that we could take from legumes and that’s why we like legumes so much.
3:21
The second portion of my master’s work was to look into some nitrogen dynamics and seeing how is that nitrogen being transferred deep in diving into some mycorrhizae benefits from having a legume in the system.
3:33
So we basically had Ryegress and Crimson Clover mixtures and then we were blocking that contact with a mesh that was enough to also block mycorrhizae
3:43
And then to try to understand that we use some nitrogen gas that was traceable.
3:48
So we were applying on one side, trying to track the other side on the plant either in the root or the above ground biomass.
3:54
Turned out that root contact, it’s very, very important. For my PHD I stayed in Florida, really liked it.
4:02
But I don’t mean to cover crop and integrated crop and livestock systems, but always having that legume component into what I was doing.
4:09
We looked into business as usual, not doing cover crop, leaving that land as it was into into the summer, but also integrating livestock into the system.
4:21
So the idea behind it was basically understand how grazing those cover crops, not having cover crops or adding the legume into the mixture would affect row crop performance.
4:32
For my reality, there was cotton peanut. Little side project from my PhD was actually a grazing trial that took three years.
4:44
So not quite small project but we looked into this project was funded by Cortiva and we looked into infested pastures with Amaranthus Spinosa’s pigweed here.
4:54
So we had a clean pasture, 1 pasture that was half infested and one that was heavily infested.
5:00
Looking into animal performance, how would affect the animal performance having that pasture infested clean or have been also understanding how it would impact the forage production?
5:13
So, but the most important portion of everything was delivering the message to the producers, the stakeholders of course, to the funding agencies that give us the money to do what we do, but also make sure that that message was always delivered.
5:27
But now I’ve been in the Midwest for three months so far, and I’ve talked to folks from the industry in the seed companies, producers, educators, researchers, and winterkill.
5:41
It’s quite something that Alfafa faces as a trouble.
5:49
And I cannot talk about winterkill in Alfafa without talking about potassium and the importance of potassium and stress of of plants.
5:56
Potassium is important for many things, but I could highlight especially the stress tolerance in plants and for Alfafa is not different.
6:05
So we have potassium always controlling once we get the CO2 from the atmosphere and as we increase the leaf concentration of potassium, we do can we can boost that photosynthesis in a plant.
6:20
And this is actually for alfalfa itself.
6:23
And the current knowledge is that potassium is the golden ticket for alfalfa persistence.
6:29
If we look into our current guidelines for Wisconsin, we have alfalfa taking up to 60 lbs for each ton of dry matter produced, right?
6:40
So if we have a six ton hay field of alfalfa, you’re taking more than 340 lbs as K2O.
6:45
That’s a lot of potassium.
6:47
But Marta will have some updated numbers for you on, on, on that matter.
6:55
But here also Chris already explained to you how they are looking into changing those, those requirements for soybean, corn.
7:05
But we also trying to work on some for for Alfafa extremely needed.
7:10
And for this guideline A2809 that we currently have, they say that if you want to stand to persist more than two to three years, you have to increase those requirements wherever your soil is telling you or your production is related by 20%.
7:28
That’s a lot of potassium.
7:29
And then Scott was asking about the response to potassium of being economically available.
7:35
Perhaps good news alfalfa is taking that potassium quite a lot.
7:40
But the beauty is sometimes you do not see the need of the potassium once you, you’re going through some drought stress or a bad winter kill event and you always lose some plants, you have some crowns damaged as you dive into the, the, the winter and then you ask, but we do apply one year, right?
7:59
So in those, in those guidelines, as Chris mentioned, you will have a bunch of tables available for you.
8:04
This one is related to the first year available nutrients.
8:08
Once you apply one year, let’s look just into potassium here, into the liquid one year, you’re looking at 11 or 17 for each pound for 1000 gallons.
8:18
We are really behind on the amount of potassium that Alfafa is actually requiring.
8:25
We also would like to point out the importance of sulfur, especially if you want those nutrient credits from of alfalfa, especially nitrogen.
8:33
You need the nodules working and from those nodules to work quite well.
8:37
We do need sulfur.
8:38
You need other elements of course such as Boron Molybdenum, but sulfur it’s quite important also part of chlorophyll
8:45
And if you want to dive into the importance of so it, how much nitrogen can alfalfa fix, I will tell you, it depends, right?
8:54
That’s so you can go from 50 from 45 to more than 300, 400 per nitrogen per acre per year.
9:03
But the current knowledge that we have regarding to sulfur is that due to improvements in air quality, we are not getting as much sulfur deposition as we used to.
9:13
So just if you look at this graph here below, in the total sulfur in the last 10 years, that’s what we used to get.
9:19
That’s where we’re getting right now.
9:22
And how much is Alfafa taking on sulfur per ton of dry matter produced?
9:28
We can have a range of five to six or 36 per year if we are considering that your field is producing 6 ton.
9:36
And also always important to test for the tissue concentration that you have in the guidelines.
9:43
Here is your low, here’s your sufficient and then your high.
9:48
And then again talking about the fertilizers that are available, it depends if you need a quiet correction, a fast correction on your field, you’re looking into some sulfate form of sulfur and then the elemental sulfur will not be available for you right now.
10:05
So it needs to be incorporated either before because you have to count that that would not be readily available.
10:11
And in the Manure here you will have if you apply a total of multiplying this for the amount that you applied 4.5, you will have available available a little bit less than that if you apply 4500.
10:32
Going back to the importance of alfalfa, that deep root taproot that you need to get all those nutrients does depend on potassium again.
10:42
So the development of roots, potassium is very important for that as well.
10:46
As I was preparing for this with Marta, I was digging into the literature.
10:50
Some of them were talking about the importance of potassium also in cases of water logging, but not only in you had some wet springs that I’ve heard of.
11:00
So not only the importance for the short droughts that you’re getting more frequently, but also the water logging.
11:06
Did I find data for that?
11:07
No, I did not.
11:08
But at least I mentioned it to you.
11:09
So you have one more thing to be aware of and then just I know you will have access to those to those slides here just talking about some nutrient deficiency symptoms that I would like to to point out.
11:24
So we put this together trying to look into where first you look for those deficiencies.
11:29
You can start, start in the terminal leaflets in young leaves, in old leaves.
11:34
Of course, this is not a cake recipe.
11:36
So for some of those you might get into throughout the whole fountain sulfur, it’s one of those examples here.
11:46
We were trying to put all those pictures together.
11:48
Boy, it was hard to get those pictures, especially when looking into into this one was one of the hardest ones for calcium.
11:56
But also those we don’t have available because mostly if you’re talking about those deficiencies, they will come with other deficiency.
12:03
And then things get more interesting for you to take a picture and point out you will look and it’ll be chlorotic eaves.
12:09
Great.
12:09
Thank you.
12:10
Yeah, most deficiencies will will start just like that.
12:13
So, but this is something that we can work on and with Marta that’s an effort that we’re trying to get for you.
12:21
We will succeed let you know next year.
12:23
So that’s something that you can keep.
12:26
And then just for since we are focusing more in potassium right here, most of the deficient sometimes can be confused with some damage from potato leaf hopper at the very beginning.
12:37
But towards the end alfalfa will start with those little, it’s quite hard to see, but those little red yellow dots in here.
12:47
And then I hope you it can be of assistance those pictures for you.
12:52
And then you will hear about some nice data about nutrient exports from alfalfa.
13:00
Good morning.
13:02
I’m Marta Kohmann
13:03
I’m your forage Extension professor.
13:05
Every time I hear people calling me Doctor Kohmann, I like freeze and think, am I in trouble?
13:11
It’s kind of like having your teacher call you by your, your full name, You know, Marta Kohmann
13:16
I was like, I always get a little bit scared.
13:19
The other thing that comes to mind is I actually have a twin sister who is a medical doctor.
13:23
So I also look over my shoulders like, is she here?
13:26
Is that who you are calling?
13:28
So I do prefer you call me Marta, if that’s OK.
13:31
And as I mentioned, I’m your Forage Extension professor and this is my third growing season here in Wisconsin.
13:40
So getting used to having seasons, I really enjoy that.
13:44
And in the past three years, a number of questions have come up about alfalfa management.
13:52
I feel like there is a lot of recommendations that need to be updated.
13:56
So that’s something I’ve been working on in the past past three years.
13:59
So today I’m going to present data on this study where I was looking into applying manure into alfalfa stands.
14:09
So this was a interseeded alfalfa stand.
14:13
Have you guys heard of interseeded alfalfa corn systems?
14:16
Yes.
14:17
So I’m going to apologize to Harkirat
14:19
14:19
I’m going to ignore the corn for now.
14:22
This is a second year experiment, so it’s only looking at the alfalfa stand.
14:28
And what I evaluated is application of manure in four treatments, no manure.
14:35
I always like having a control. Application of manure in the fall, in the spring or in the fall and spring.
14:43
So 2 applications of manure and we’re looking into how that is affecting production and how is affecting nutrient removal, which we heard a lot about today.
14:56
We also collected some soil samples to see if there is any change in nutrient concentration and each manure application was 4500 gallons per acre.
15:08
All right.
15:09
So first thing that I wanted to mention is, and I do, I do apologize, but this soil samples that I analyzed, I analyzed using Malek 3, which is a little bit of a stronger acid for extraction then the nutrient levels might be a little bit higher than what we would get with Ray.
15:27
All right, we all know this table, right?
15:31
This is showing which category your soil would be considered in different levels of concentration.
15:39
So this is where we started.
15:40
So I ran this study in two locations, Arlington, Prairie du Sac and let’s focus on the concentration of phosphorus first.
15:49
They were excessively high, looking at potassium excessively or very high.
15:55
So there was a lower chance of those soils responding to nutrient application, right.
16:02
So we know how the soil is, let’s look at the manure nutrient concentration.
16:07
So at each one of these two locations, the reason why I chose them is that there is a dairy in Arlington and there is a dairy in Prairie du Sac.
16:16
So I could source liquid manure at each one of those those locations.
16:21
So again I have a no manure treatment and you can see each one of those roles is showing nutrient concentration in terms of nitrogen, phosphorus and potassium and then each one of those treatment applications, right.
16:34
So we have a fall, a spring and a fall and spring.
16:38
So around 50 to 70 lbs of nitrogen per acre for applications.
16:46
So fall in spring treatments received twice, two applications rights around 130 in terms of phosphorus around 10 lbs and potassium around 50 lbs.
16:58
So let’s see what happened with forage production.
17:00
So this table of excuse me, this graph here is showing how much biomass I produced throughout the entire season.
17:08
OK, so this is summing the four cuts, the four harvest we had together.
17:13
So in Arlington, I didn’t see any manure treatment effect.
17:19
However, let’s look at Prairie du Sac.
17:21
The biggest difference in terms of nutrient concentration is in terms of nitrogen.
17:27
In the fall, that nitrogen concentration was surprisingly high, right?
17:33
And what happened was when we compare the production of forage in the no manure fall, spring and spring and fall, there was a bit of an increase in production around 20% when we look at the total season with that fall manure application.
17:52
Now I also wanted to take a look at how if that changed over the season, so with that manure application change how alfalfa behaves.
18:02
So again, there was no effect of manure application on the on this responses, but there was an effect of harvest time, which makes a lot of sense, right.
18:14
This is a very typical alfalfa behavior in terms of harvest of biomass, right.
18:21
The first cut makes up 50% or less of the total biomass in the year, and then we start seeing a reduction of biomass as the season advances.
18:32
And these were harvested every 28 days, right?
18:37
Let’s see, crude protein.
18:39
I always like to look into nutritive value when I’m looking at forage management because my end goal will be to feed animals, right?
18:48
So I like to collect that data.
18:50
Even though I know alfalfa is going to do great, I like to know how exactly it’s doing.
18:56
So again, in Arlington, the behavior is very typical, right?
19:00
A little bit lower nutritive value, lower food protein in the beginning, increasing at the end. in Praire du Sac.
19:09
I thought it was very interesting that the first cut had pretty high nutritive value, pretty high crude protein.
19:16
And what I think is happening is just that there was that very high nitrogen concentration in the manure in Prairie du Sac
19:24
So I think that is what is feeding into that higher nitrogen concentration in the alfalfa and then similar similarly in digestibility, we see that lower level in the beginning and then an increase in digestibility as the season advances.
19:43
So, so far very well behaved data.
19:46
So let’s take a look at at nutrient removal.
19:51
The first thing that I wanted to do is, let’s just comparing the two locations, Arlington and Prairie du Sac I have the average production on top, right.
20:01
4.5 to 5 tons of dry matter per acre.
20:08
So looking at removal rates, so for P2O5 was 14 to 18 lbs per acre removal and for K2O was 73 to 77.
20:21
So let’s let’s go back to that table that we have in A2809 and compare that compared to the table, these values are higher, right?
20:32
So for for phosphorus, the data that I collected was 7 to almost 40% greater and for potassium it was 20 almost to 30% greater.
20:44
So to me what that indicates these are only two locations is only one year.
20:50
But I think that what this data is showing is that this is worth investigating, right?
20:56
We are removing quite a bit of nutrients.
21:01
Let’s look at the balance.
21:02
And this is, I’m just looking at how much phosphorus I’m adding to the system and how much I am removing with the biomass.
21:11
So we’re adding this is P pounds of P per acre, 9 to 5.
21:18
We’re removing more than 30, so 30 to 40.
21:22
This means that we have a negative balance, right?
21:25
We are removing phosphorus from from that system.
21:30
In terms of potassium, that magnitude is going to be greater, but the story is going to be very similar.
21:36
We’re applying 40 to 50 lbs of K per acre.
21:40
We’re removing around 300.
21:43
So again, our balance is negative, right.
21:46
We are removing more potassium than what we are adding.
21:50
And just a small disclaimer here, I’m not considering other sources of nutrients.
21:56
So for example, especially for phosphorus that atmospheric deposition similarly to to sulfur atmospheric deposition can be pretty important for for phosphorus as well.
22:09
All right, OK.
22:12
In terms of other nutrients, I was just surprised with the amount of of magnesium that was being removed more than 30# per acre.
22:20
In terms of sulfur also we estimate 23 lbs of sulfur per acre for 4 tons of dry matter production.
22:29
And I also again found that the production was a little bit greater, but the amount of sulfur that we’re removing was greater than the difference in yield.
22:39
So what that indicates to me is again, we might be under estimating how much, what’s the different concentration in the plant tissue, so how much we are actually removing.
22:51
Interestingly, what we did notice is that in terms of concentration in the plant tissue, we have this threshold of .25% to identify whether or not alfalfa will respond to sulfur application, right.
23:07
So if it’s .25 and up, it will most likely not improve in terms of yield when you apply sulfur and we can see that we are A OK by the
23:21
Concentrations in terms of sulfur are above that threshold
23:26
One thing that I looked in the literature and it seems to make sense.
23:30
I would love to hear from you, but most fields that receive a lot of manure application will typically, typically not struggle with sulfur deficiencies.
23:42
So let’s go back again to what my colleague Luana was showing in the beginning, which is typical concentrations of of sulfur in different manure sources.
23:54
So if we look at available manure, available sulfur in manure form, very liquid manure types, we apply around 4500 gallons.
24:07
So we get more than 10 lbs of sulfur in that application for application.
24:13
So for example, for the following spring treatments we are getting 20 lbs of of sulfur per acre.
24:22
But that does that make sense that resonates with with people in the audience?
24:27
Yeah, OK, perfect.
24:30
So again I wanted to look at the soil characteristics.
24:33
Again, this was not Bray, this was Malek 3.
24:35
So the value might be a little bit higher than then we would get it for analyzing Bray.
24:41
But the take home message here is that there was a change in concentration in in phosphorus, potassium, sulfur and magnesium.
24:53
So there is a we are in fact removing nutrients.
24:58
I think that is the take home message.
25:00
We are affecting our system when we’re harvesting biomass.
25:06
So conclusions of course if the soil levels of nutrient are high, there is a lesser chance of our crops responding to nutrient inputs and we know that or there is some indication that alfalfa is removing more nutrients than what we have in our current recommendations.
25:28
So this is definitely something that we are fighting for funding to get this work done and get more data points.
25:35
Again, this is 32 data points.
25:38
It’s a very small data set compared with what corn and soybean had was just almost 2000 points.
25:44
So little by little we really want to build up this data set to get really good data for you.
25:55
So we are working to update those recommendations.
25:59
These are the current resources that we have.
26:02
Again, we are looking to updating this, but they are a great way to to start.
26:06
So there is the general 2809, but then also there is more specific information for each one of the different, different nutrients that is very useful.
26:17
All right, this is what I have for you today.
26:20
Do we have any questions?
26:24
So the question was, was there a difference in total nutrient, nutrient removal in the no manure control compared to the plots that receive manure?
26:32
No, It didn’t.
26:33
And the reason why was the concentration of nutrients was very similar across the treatments and the biomass ended up being similar as well.
26:43
So again, those soils were already pretty high in phosphorus and potassium.
26:47
That might be one of the reasons why we didn’t see any effect.
26:49
I’d love to repeat this experiment lower nutrient status type of soil to see if we see any differences.
26:59
Yeah, thank you for that comment.
27:01
So the comment is we need to update this estimates of nutrient removal.
27:06
And that definitely, yeah, that’s that’s a main concern of mine is identifying what are my stakeholders in need.
27:16
And that was one of the questions that was coming up, that that’s one of the motivations behind this experiment.
27:21
And again, that’s one of the motivations for us teaming up with Chris, me and Luana to get more information.
27:28
Hopefully we’re going to get that funding, be able to run this samples because it’s a little expensive to run this sample for plant tissue.
27:35
I’m seeing some people nodding.
27:38
So actually for this experiment, I couldn’t analyze each one of the cuts of alfalfa.
27:44
So I did a weight average of the four cuts to make sure that I’ll get like a good, good idea of what was happening in this season.
27:55
And just a final comment.
27:57
I know we’re just about to eat lunch.
28:00
OK, Another comment in terms of how yield is changing over time.
28:05
I was again looking at the literature.
28:07
I think Juan and I spent a good month or so just scavenging what was available.
28:13
And there’s a lot of data, but it’s a little bit old.
28:16
So from the 2000s maybe I think was the the closest to what we have now or where we are now.
28:24
And I found this one paper that shows how yield in alfalfa has increased.
28:31
So they were looking into what seeds we had available in the 70s, eighties, 90s, all the way to the 2000.
28:39
And there was a very clear increase in yield for the alfalfa stems.
28:45
And that was very much related to disease resistance, how that had increased over time and that helped alfalfa yield, alfalfa production.
28:54
So I haven’t seen something with data closer to now.
28:59
Again, there is a lot of work that needs to be done in alfalfa, but we are excited to be a part of of that.
29:06
Question was what time of year did we apply the manure.
29:08
So we applied that in the fall.
29:11
So we harvested the corn in September, allowed the alfalfa to grow a good four weeks or so and applied the manure for the fall treatments in October.
29:24
And then in the spring we have to apply after the first cut.
29:29
Because if you remember spring of 2024, it was very difficult to get into the field.
29:36
I may or may not have fallen in in one of these experiments.
29:40
It was like walking on soap.
29:43
So those were the two timings.
29:48
Yes, just surface apply.
29:51
Good question.
29:52
Yeah.
29:53
So the question is what are some other techniques to apply this manure so that we are not disturbing the soil, we are not having nutrient ran off.
30:04
I don’t know.
30:04
I think that might be a question to the afternoon.
30:08
Speaker.
30:08
So Malika Nocco is going to talk a little bit about different irrigation systems that could potentially be used for manure.
30:16
But I’m going to plug in just because we’re talking about traffic as well, that we have been doing quite a bit of work on that.
30:23
We’re going to present some of it already in the Ag Classic, but we found a reduction in yield due to traffic of up to 20%.
30:32
What surprised me the most is how much machinery traffic is hurting the below ground biomass.
30:39
And then I show some data on the the roots and they’re, they’re really suffering from the traffic stress.
30:46
Great question.
30:47
OK, I’ll be here also for for the day.
30:50
So if you have other questions or comments, ideas for things I should be looking at that you haven’t heard about yet, I’ll love to hear those as well.
Soil Infiltration and Aggregation: What’s in it for you?
Dr. Mallika Nocco, assistant professor and extension specialist, UW–Madison Department of Biological Systems Engineering
Dr. Mallika Nocco, assistant professor and extension agrohydrology specialist, UW–Madison introduces key concepts of soil health, focusing on two critical physical indicators: infiltration and aggregate stability. This presentation explains how soil structure, texture, cover crops, and root systems influence water movement and soil resilience. Learn practical strategies to improve infiltration, reduce runoff, and enhance aggregation for better crop performance and nutrient retention. Mallika also shares simple field tests for assessing soil health and discusses how these principles connect to irrigation, manure application, and conservation practices.
Transcript
0:05
Hi, everyone.
0:05
How are you?
0:07
Yeah, I’m doing great.
0:09
Love Appleton, love the BBQ lunch here.
0:12
So that that’s pretty fun to be on after the barbecue.
0:16
And I am excited to talk with all of you about soils and soil health.
0:21
So I’m just going to do a little introduction.
0:24
We’re going to talk just about soil health more generally and then about infiltration and aggregation specifically.
0:29
And then what’s in it for you?
0:32
OK, so my name is Mallika Nokko.
0:34
I’m a little bit new.
0:35
I started like in 2024, early 2024.
0:38
My lab is called the Conservation Irrigation Lab, but we do more than irrigation.
0:44
So we also work with rain fed growers and we work on precision mapping of crop water stress and evapotranspiration.
0:52
We work with like a lot of different types of soil moisture or soil water potential sensors and like thinking about sensor optimization for decision support.
1:00
And then also very interested in this like space with soil health and regenerative agriculture, specifically the physical part of it.
1:08
So we do physics.
1:11
When you meet someone who does water management or agrohydrology, often times there’s a lot of physics that get embedded in there.
1:19
OK, here is the definition of soil health, the continued capacity of soil to function as a vital living ecosystem that sustains plants, animals and humans.
1:32
Who has heard this before?
1:35
Anybody?
1:36
All right, all right, a couple folks.
1:38
This is the NRCS definition and it’s been around for a long time, you know, well, well over a decade, probably about I think over 15 years maybe at this point.
1:46
And it’s kind of the agreed upon definition of what we think about as a healthy soil.
1:51
Who has seen this before?
1:54
OK, cool!
1:55
Some people.
1:56
Does anybody who has raised their hand want to say what this is?
2:00
Yeah, Yeah,
2:00
So kind of getting at that.
2:01
It’s a, we call these the soil health principles.
2:04
And these are actually from DATCP.
2:07
So this is Wisconsin’s, you know, interpretation of key soil health principles that you can integrate into your operation.
2:16
So the principles themselves are minimizing disturbance, maximizing living roots, maximizing soil cover, maximizing crop diversity, integrating livestock, and in the center we integrate the farm and the farmer.
2:30
And I think of these principles as just a, a great kind of entry, entry point into engaging with soil health.
2:37
So we very much don’t have to be all or nothing about this, right?
2:42
So trying to engage with these principles, incorporate practices that are related to these principles into operations in a way that makes sense for you is what we are going after.
2:55
So those are the principles.
2:58
And let’s say the principles are related to practices.
3:00
So like, let’s take a pause.
3:02
What are some practices that would maximize the presence of roots on a farm?
3:09
Cover crops.
3:10
Thank you.
3:11
Yeah, maximizing the presence of roots with cover crops.
3:13
So that that’s an example of a practice.
3:15
So you have a principle which just like, let’s have roots on the ground, a practice, cover crops, and then indicators which we use to kind of measure or assess how well these practices are working.
3:28
So for soil health, there’s three categories of these indicators.
3:32
There’s biological indicators, chemical indicators, and physical indicators.
3:37
And maybe because I do the physical part of things, I feel like the physical indicators don’t get as much attention as the others.
3:45
And that’s why I wanted to talk about two.
3:47
We’re just going to talk about two really important physical indicators today.
3:53
Maybe the next time I come, I’ll pick a different physical indicator.
3:56
But I mean, all these indicators are important, but we’re going to focus on 2 very important physical indicators and they are infiltration and aggregate stability.
4:10
OK.
4:11
So indicators…there’s actually a lot of discussion on like what indicators should look like and what they should be.
4:18
But another kind of way of thinking about this, this is a rubric that came from the Minnesota Office for Soil Health and also Washington State.
4:25
And it’s more of like, the indicator is in this question framework, which I like.
4:30
So the first one, you know, in answering this question of like, is your soil healthy?
4:36
Does it blow away or flow away?
4:39
So should the answer be yes or no for a healthy soil?
4:45
It should be a no.
4:46
That’s right.
4:46
That’s right, it should be no.
4:47
You don’t want your soil to blow away or flow away.
4:51
And that kind of gets at the aggregate stability part, right?
4:54
If you have good aggregate stability and you have aggregation in your soils, they won’t blow away or flow away.
5:00
Does water soak in quickly for a healthy soil, should it be yes or no?
5:05
Yes.
5:05
Yep.
5:05
And that is that concept of infiltration.
5:08
Does it drain?
5:11
Yes.
5:11
Yep.
5:11
So for a healthy soil, that should be a yes.
5:14
Again, getting back to that infiltration, does it crust?
5:18
No.
5:18
Yep.
5:19
Yeah.
5:19
You don’t want it to.
5:20
Crusty bread good.
5:22
Crusty soil bad, right?
5:24
So we don’t want it to be crusty.
5:26
Does it recover most of the nutrients you apply?
5:30
We hope so.
5:31
Right.
5:31
For a healthy soil, are there areas where plants just die?
5:35
That’s not healthy, that’s not good plants just dying, it’s not a not a good sign.
5:39
And I like this too because at the bottom here, it’s like probably healthy, probably not healthy.
5:44
And that’s acknowledging that there could be other stuff going on, right?
5:47
Soil is very, very important, but there are other parts to your system that are also very important.
5:53
So this is kind of thinking in more of soil health in this like restoration degradation framework.
5:59
And this is just because we are all starting with soils that are at different kind of phases, different points.
6:05
Like maybe you’re starting, you know, you have a virgin soil.
6:09
Like there was a person where we were in Monroe yesterday and they’re like, well, I’m was started with this virgin soil and started cultivating it and it was magical.
6:17
OK, so you’re starting at this place that’s pretty healthy, right?
6:21
You have a soil that hasn’t even been cultivated and has always kind of been living with the soil health principles.
6:26
Or maybe you’re starting with a very degraded soil.
6:29
So kind of thinking in terms of like where are you on this helps to think about like what how you should apply the principles or integrate them to either build the soil or maintain it depending on where you’re at.
6:42
All right.
6:43
What is infiltration?
6:45
What does it sound like it would be?
6:51
Yeah, maybe students over here.
6:53
What does it just sound like it would be?
6:57
Yes.
6:58
Yep, that’s exactly what it is.
6:59
It is just water moving into the soil profile.
7:02
And so an infiltration is a process that I think of that’s like in tension with runoff.
7:10
So when we have rain coming down, what could happen to that rain?
7:14
It could go into the soil profile, or it could run off.
7:18
And if you have a healthy soil, you want it to go into the soil profile.
7:24
All right, this is a tricky concept, but an important one to think about infiltration rates.
7:30
So we talk about infiltration in terms of rates.
7:33
So there’s, you know, a unit over time, so inches an hour and it starts pretty fast.
7:41
And then it reaches this point of steady state.
7:44
And the reason that infiltration rates start fast is because soils are not usually completely saturated and there’s still space for the water to fill up.
7:56
So that’s why you have kind of fast infiltration rates in the beginning, but then as the soil fills up with water, you kind of hit this place and we call this steady state infiltration rate.
8:07
So infiltration in and of itself is something that is changing.
8:11
It’s dynamic.
8:13
And I bring that up because I want to talk about differences in infiltration.
8:18
And when we talk about differences in a rate, like how do you even do that comparison, right.
8:23
So this when we were talking about differences, these are all steady state infiltration rates.
8:28
And so this is just showing you that infiltration varies by soil texture pretty significantly.
8:36
And it varies so much that we have to, I had to put two columns on here.
8:39
This one’s inches per hour and this one’s inches per day.
8:43
So if you think about sand, you know, you’ll have 1.6 to 8:00-ish inches per hour.
8:50
And that I can visualize, right, we can kind of think about, OK, you get an inch of rain like it’ll in a sandy, sandy, sandy soil.
8:56
It’s going to take maybe an hour, right, for it to infiltrate or a little over an hour.
9:01
But I cannot visualize what this is in a clay loan .09 inches per hour.
9:07
That doesn’t make any, I can’t visualize that I can visualize 2 inches over the course of the day.
9:15
And I wanted to show this to all of you just to see just how much soil texture does impact the infiltration rates that we see.
9:25
And I know for those of you who are farming, this is probably pretty intuitive, but just the fact that you go from an hour to a day, from sand to a clay loam is pretty, pretty fascinating.
9:37
Yeah.
9:40
This is just ignoring soil health.
9:42
This is just texture.
9:44
But good question.
9:47
OK, yeah.
9:48
So we kind of have to build some build some concepts before we can talk about the healthy or unhealthy soil.
9:53
So that I would say that graph like the data that this comes from, it’s like kind of not looking at differences in practices.
10:02
So they’re looking at representative soils of these varying textures.
10:06
But great question.
10:08
All right.
10:09
Do we have any irrigators in here?
10:11
Anybody irrigating?
10:13
OK, some irrigation, irrigators.
10:15
So if you are an irrigator, you have to care about infiltration because you have to set up the rates of your irrigation to match the infiltration of your soil if you want to irrigate as efficiently as possible.
10:30
And these are just showing you two different like wetting zones.
10:32
So sandy loam, you know, this is the 15-minute wetting zone in depth.
10:38
I think it’s really interesting too with the clay loam, you have more, more spread just because of the structure of that, that particular soil and the pore space in a clay, it’s going to kind of spread out wider a little bit more and it’s going to take a lot longer, of course to infiltrate.
10:58
So infiltration also depends on soil moisture.
11:01
And we talked about this a little bit.
11:02
If you start out with a very wet soil, you’re heading towards the direction of steady straight state infiltration.
11:11
You’re going to get to that steady state infiltration rate faster than if you have a drier soil.
11:18
All right, this is kind of cool.
11:20
And this is getting to your question a little bit.
11:22
So this is comparing, the way that they did this is
11:24
They’re comparing a, they’re saying wetter antecedent conditions, conventional tail or a soil with a crust is going to have a slower rate in the beginning then drier conditions, a no till soil or a more uniform soil.
11:40
So starting to kind of think about healthy and unhealthy, right is where you where they’re going here.
11:46
They’re just putting, they’re lumping some of these things together, which is interesting.
11:51
All right.
11:52
This is getting to that soil principle, soil health principle of maintaining roots.
11:56
So the way that water moves through soil is contingent on the presence of roots.
12:03
So when we think about just from a hydrologic perspective, a soil that doesn’t have any roots in it, we call this bulk flow.
12:13
And we visualize it as the water is kind of moving uniformly into this bulk, bulk flow soil.
12:21
But the presence of roots introduce what we call preferential flow paths.
12:27
And so just by pushing into the soil, there’s additional flow paths.
12:31
And this is like a little bit, this part kind of blown up here.
12:35
So you can see just along the roots, there’s this root oriented flow that’s happening.
12:40
And then there’s the bulk flow as well.
12:42
So you can have more infiltration, deeper infiltration when there is the presence of roots and that’s any roots, roots versus no roots.
12:54
Ok, again, getting to this question of infiltration rates, this is looking at the same like the texture, so different soil textures, but covered versus bare.
13:04
So another one of those soil health principles is trying to keep the soil covered.
13:08
So if you have a covered soil, is it going to infiltrate faster or slower?
13:16
OK, interesting.
13:19
Tell me why you think that might be.
13:23
So I think that that makes intuitive sense at first, but the problem is if you leave the soil bare, it’s going to get kind of crustier.
13:32
So actually the finding is a little bit counterintuitive there in that you are going to have a little bit faster rates with the covered soil than the bare soil.
13:42
I suppose it depends on what it was covered with.
13:46
And I think for this table and this study it they were assuming covered in some sort of residue, a cover crop.
13:57
So covered by a cover crop or covered with additional residue.
14:00
Yep.
14:02
OK.
14:03
But interesting conversation.
14:05
All right.
14:06
So infiltration also depends on the structure of the soil.
14:09
And this is something that I was talking about a little earlier and that there’s kind of this tension in the water budget between infiltration and runoff is almost opposing processes in soils, right.
14:23
So if you have an out aggregated structured soil that has old, you know, worm channels in it, there’s a lot of these flow paths and you’re going to see more infiltration and less runoff versus if you, you know, don’t have as many aggregates, you have some crusting, you’ll see more runoff.
14:45
You mean in terms of like infiltration of nutrients and water?
14:51
Yeah, Yeah, absolutely.
14:52
Infiltration is so like those of you who might be irrigating, if you’re fertigating, right, you’d want to have maintain and try to improve your infiltration rates.
15:01
Yeah, absolutely.
15:03
OK, so how do we measure infiltration?
15:06
We call these not so creatively infiltrometers.
15:10
And there are many different kind of approaches and ways to do this in the research world.
15:15
There’s a simplified approach if those of you want to engage, like let’s say you want to try some soil health practices and just get a feel for what the infiltration rate might be on a soil.
15:26
And we’re going to share these slides.
15:29
So I’m not going to play this video because it’s like 10 minutes long.
15:33
But I just wanted to tell you there is a link to this video of how to do this.
15:36
And it’s kind of a simplified approach.
15:38
And basically what it is, is using like a six-inch ring and hammering it just a little bit into the soil.
15:45
So there’s contact and it’s below the soil.
15:48
And then putting a piece of plastic wrap down, having a timer and putting a known amount of water.
15:55
So like, you know, I think in the video he uses 500 milliliters or a half a liter, but a known amount of water and quickly pulling out the plastic wrap and starting your timer and just seeing how long it takes for that known amount of water to infiltrate.
16:11
And that would be something.
16:12
So I whenever I talk about soil health, sometimes people ask this question of like, how long does it take for something like cover cropping to make a difference?
16:23
And it does take years, right?
16:26
But if you’re going to start something like that on a new field, this is the kind of thing that might be interesting to do before you get going and it kind of start checking right for yourself and using a strategy like this, this test that he will show in this video with like a coffee can hollowed out.
16:45
We wouldn’t use that in a study, but it is useful to see relative differences, right, on a farm, if you don’t want to like buy an infiltrometer and learn soil physics.
16:56
So that’s kind of useful in that respect.
16:59
So I just wanted to point out that there are ways to just get a feel for this.
17:02
You know, we were talking to somebody and they’re like, oh, I get a feel from it by just watching puddling and how long puddles take to infiltrate after rainfall.
17:11
That’s legit too.
17:12
That’s another way to like see whether these practices are doing anything for you.
17:16
Oh, ok, great.
17:20
Ok.
17:21
So moving into aggregation, so what is a soil aggregate?
17:26
They’re interesting.
17:27
They’re soil aggregates.
17:29
There’s microaggregates and macroaggregates.
17:32
So this is a larger aggregate, but it also has these little aggregates in it.
17:37
And if you just look up the definition of aggregate, like what does it mean to aggregate?
17:42
It means to come together.
17:44
So, this is a coming together of particles of soil, of organic matter, of root matter and roots, a lot of things that in addition to the soil particles themselves are making it sticky.
18:00
And that stickiness is good because it’s causing this, these aggregates to form.
18:07
Ok.
18:07
So again, like thinking about the difference between a larger macroaggregate and a microaggregate, this, these, this artwork is from the Minnesota Office for Soil Health.
18:18
And these aggregates, I think it’s very important to kind of think about clay and silt are important for aggregate stability and for aggregation in soils.
18:29
It’s actually kind of hard to improve aggregates and to get very sandy soils to form aggregates because they don’t have as much of the clay and the silt, which are sticky.
18:41
And it’s actually really hard to get sandy soils to accrue organic matter.
18:47
Same reason they just don’t accrue organic matter as fast as clay or so.
18:52
So if you have a sandy soil, you have to be a little bit more patient with some of this stuff and soil health can just look a little bit different for you.
19:01
OK, so this looks pretty good.
19:04
So here’s an aggregate we, you know, or here’s some aggregates in a soil.
19:10
So here’s a soil with aggregates in it and there’s water and it’s infiltrating and it’s kind of, you know, starting to go in it and but the aggregates are all kind of the same size, ish, right?
19:24
So let’s look at one.
19:26
This one has aggregates, but the aggregates are different sizes.
19:32
So there’s like a diversity of the aggregate size and there’s larger aggregates generally.
19:39
So we call those, you know, like the macroaggregates, and then we see larger pores and we call those macropores.
19:48
So when we see infiltration come through, there’s larger pores and kind of highways for the water to move in.
19:55
This one also has more roots present in it.
20:00
So we mentioned this already, but just hitting on that point that clay and silt are sticky.
20:04
So when it comes to the aggregate stability and improving aggregation, the presence of clay and silt are actually a little bit helpful.
20:12
I know that in other areas, you know, when we talk about drainage, like a lot of clay can be a problem.
20:18
Ok, I like to think about this one.
20:21
This is aggregate stability and let’s talk about roots again, looking to what I think, are you guys students?
20:28
Is this a student corner?
20:30
Ok, I could just the vibe, it’s a vibe.
20:34
So maybe looking to the students, but maybe everybody.
20:37
Does anybody like science fiction?
20:42
Nobody wants to, like, come out for science fiction right now.
20:46
Just so I bring this up because I wanted to ask, do people have you heard the term terraforming?
20:53
People heard that?
20:54
Yeah.
20:54
What is?
20:55
Yeah.
20:56
Oh, thank you.
20:57
I’m not alone.
20:58
I thought I was the lone nerd up here.
21:01
What does terraforming mean?
21:04
How do you think of that word?
21:07
Creating an environment?
21:09
That’s fantastic.
21:10
Terraforming I think of as creating an environment.
21:13
I don’t know about you, but whenever I hear or think about terraforming, I always think of like humans going to another planet and trying to make it hospitable for us to live, right?
21:23
And a part of that is like making plants and soils.
21:26
I bring this up because plants actually terraform right here, you know, all the time, all the plants, cash crops, cover crops, any crops, any plants are terraforming.
21:37
And this, this is a new study and it’s really cool.
21:40
And basically it’s showing you a non-compacted soil and a compacted soil, same plant and the same plant in these two types of soils is going to behave differently.
21:50
So if a plant is in this compacted soil, what it wants to aggregate it, it’s like I’m going to try to make the soil, the soil of my dreams and it will release more of something that we call a mucilage.
22:03
So it actually will take some of the carbon and put it towards mucilage formation to try to help form aggregates and make that soil stickier and stick together so it can have a better environment.
22:17
So that’s just an interesting thing.
22:18
Like, you know, these plants, they are going to terraform and try to make aggregation happen.
22:24
So like plants are also working with you towards a healthy soil.
22:28
But if you want those plants to use their photosynthesis to provide yields, maybe you don’t want them to put a ton of carbon into making their soil healthier.
22:41
So that’s another reason to kind of think about like, well, maybe you know, other crops, other parts of the system to just have a healthier soil is actually going to tell your plants that are on the soil to do less work.
22:54
Ok, so how do we think about aggregates?
22:57
We think about aggregates and measuring aggregates.
22:59
Well, we want to measure aggregate stability.
23:02
So we think about how like with getting back to what I mentioned earlier about does a healthy soil blow away or flow away, wet aggregate stability is kind of getting to that flow away measurement.
23:15
So you could measure wet aggregate stability by taking a sample of soil, you know, looking at your aggregates and then putting them into water and then testing it for 10 minutes and seeing how much of it dissipates, right?
23:31
And you want it, you don’t want it to flow away because that’s your flow away fraction, right?
23:35
You want it to stay in place.
23:38
And similarly, the blow away part, we measure dry aggregate stability.
23:44
And here we take sieved soil at different, you know, size fractions or aggregates.
23:49
And then we are going to shake it and then see what the mean weight diameter is after a certain amount of time in each of these different fractions to figure out like how many aggregates in these different fractions have stayed in place after the shaking happens.
24:07
Ok, I am going to play this video if I can.
24:10
Oh, it says, that says escape.
24:12
OK, let me see.
24:14
So this is showing you the wet aggregate stability test.
24:16
And this is a young Francisco Arriaga.
24:20
I think this is from like 15 years ago.
24:22
But this video has like so many views.
24:27
And I think it’s because it’s one of the best examples.
24:31
Oh, people are chuckling because it he does look really young, doesn’t he?
24:35
Because it’s Francisco, but he is doing this demonstration and it’s and I do, I’m not going to deal with the volume.
24:42
I’ll just narrate for him.
24:44
I’m not as well as him and his cool accent, but he is showing, you know, different, different aggregates from different treatments.
24:53
And so I think the one he’s pointing at right now, that’s a soil that has had the most integration of the different soil health principles, into that treatment.
25:04
And I think the middle one, the least integration of soil health principles.
25:08
Uh oh!
25:11
And this one, the last one is going to be kind of intermediary to just show you what that middle one looks like.
25:21
So this is kind of illustrating that concept of we don’t want it to flow away.
25:26
So if you can maintain that aggregate stability, try to incorporate those principles in a way that works for you, hopefully it won’t flow away, and you will be able to improve that aggregate stability.
25:38
So this is another thing I think you could probably do on your own if you wanted to check it out, right?
25:43
Mason jars, trying to get the little sieve that’s in there, the wire mesh sieve.
25:50
That’s, that’s pretty approachable if you wanted to get some sense of it.
25:54
There’s also a test from the Soil Health Institute called the Slakes Test.
25:57
That’s like an app that you could use to do this.
26:00
All right, sorry Francisco, we’re going to move on.
26:05
Ok, all right, so I titled the tox infiltration and aggregation.
26:10
What’s in it for you, right.
26:12
So what is in it for you capturing more rain seems pretty good, right?
26:16
So you get a one-inch rain event, and you want more of it to infiltrate as opposed to run off that that’d be great for your operation especially.
26:24
You know, we are having more water that isn’t showing up in like the frequently and in ideal amounts, right, as sometimes we want it to.
26:37
Sometimes a lot of it shows up.
26:38
Sometimes we have to wait for the rain.
26:40
So like ideally capturing the rain when it shows up and not having it run off.
26:44
That sounds pretty good.
26:46
Here’s some data kind of to this point from The Ohio State University.
26:52
We are going to do some of these studies here, so hopefully I’ll be able to, this is like what every new professor says, like someday I’ll have new data from your place I can show you.
27:01
So definitely looking forward to that.
27:03
But it illustrates the principle where this blue line test is equivalent to about 1 inch of rainfall.
27:11
And on the, the, the Y axis here, these are seconds.
27:15
So 3600 seconds is an hour.
27:19
So it in one, it took the conventional soy rotation in to about one hour to infiltrate this one inch rain event.
27:27
Corn, soy wheat with reduced tillage was about 15 minutes.
27:34
And then corn, soy, wheat, clover, the clover did something got to like 15 seconds to infiltrate this all the similar all in a similar soil type at the same field station in Ohio.
27:45
So just an example of like, what’s in it for you?
27:49
All right, another what’s in it for you?
27:52
I feel like people are going to know what this is here.
27:54
Who knows what this is.
27:56
Yeah.
27:57
So many people knew what that, who has these?
28:03
Yeah.
28:04
Yeah.
28:04
Do any of you have them?
28:06
How does it work for you?
28:07
Do you like using it?
28:10
OK.
28:11
OK.
28:12
What do you use this for…manure with it exactly
28:19
So you can apply irrigation with it.
28:20
I kind of want one too for research.
28:21
So I also am like, maybe I could come visit you and like see it in action.
28:26
I’m very curious about it.
28:27
So yes, these can be used to apply irrigation.
28:30
It’s an, for those who don’t have one or long for them and look at them on the Internet like me.
28:38
They are autonomous irrigation instrumentation.
28:42
So you can actually, it’s like an irrigation robot.
28:45
So it allows you to kind of irrigate or apply manure as fertigation without having to like dig a high capacity well and like invest in one spot.
28:54
And these are really nice too because you can move them right from field to field.
28:59
But guess what you have to care about, sorry, got to care about infiltration, right?
29:04
Because if you invest in one of these and you use them, you actually have some dependency between the infiltration rate of your soil and the maximum loading rate when you’re applying liquid manure.
29:18
So that’s another kind of what’s in it for you situation is if you decide to apply, you know, liquid manure fertigation and who is it?
29:26
I think it was you in the blue shirt with the blue hat.
29:29
You had mentioned this nutrient thing before, right?
29:31
So this is important.
29:32
It is important to think about infiltration and nutrient application together and to try to match those rates to each other.
29:41
So that’s my talk.
29:42
Thanks for listening.
29:44
And I think we’re on time if anybody has some questions, but you’re a good group of asking questions during too.
29:56
What about tiling?
29:58
I mean, I don’t even know where to go with that.
30:02
So what about tiling specifically?
30:08
Yeah, nobody talks about it.
30:11
OK, well, I don’t think, I guess I would say that tiling A tiled system can be a system that has good soil health.
30:22
So I guess that’s the first thing that we should say.
30:23
I think about tiling like irrigation of just like sometimes we got to put water on, sometimes we got to take it away.
30:29
So and I think of it also in the sense of there are engineered ways that we can add water to our system or take water away from our system.
30:40
And then there are like ecologically or biologically engineered ways that we can add water or drain water from our system.
30:47
So some of the soil, soil health principles I think are going to be effective in kind of improving the infiltration in the drainage of the soil in your system.
30:56
But yeah, like I am not going to say that a system that really needs to be tile drain, I don’t know that soil health practices are going to make it so you don’t need to tile drain your system.
31:10
I don’t know if that’s the question you’re asking, but yeah, right, right.
31:21
Yeah, yeah, absolutely.
31:23
So I guess for the question of what about tiling and how to interpret that, I’m not saying like we shouldn’t tile if you need to tile, like I would say that tiling, if it’s needed, like let’s think about how to do it in a way that we can also protect our waters that we all care about as well.
31:43
And so there’s a lot of kind of investigation.
31:45
Steven is here.
31:46
I don’t I don’t know if you want to opine, Steven about conservation drainage.
31:51
So I would love Wisconsin, because we’re a little bit, we’re tiling more and more than the states around us are we we’re tiling more in a newer way compared to the states around us that are just tiled right.
32:05
So I would love it if we could become like the champions of conservation drainage because that’s kind of what Wisconsin’s where conservation started.
32:15
You know, like there’s a lot of like great history of conservation.
32:17
So I would love it if we could be leaders in that way.
32:20
But I don’t think I’m definitely not saying don’t tile if you got to tile.
32:26
Yeah.
32:27
In fact, we have some new, new research where we’re going to be doing some research, thinking about soil health and tile drainage together.
32:36
Exactly.
32:38
Yeah.
32:39
Absolutely.
32:41
All right.
32:42
Other.
32:43
Steven, do you want to say anything?
32:44
No, we’re just OK.
32:46
What about you, Kevin?
32:47
Kevin is also here and knows a lot about tile drainage.
Kevin Erb
32:53
Yep.
32:53
So what we’re saying earlier was that in these head and repeating for the people that are online, the rain 360’s, we’re taking manure out there, low volumes.
33:05
The concern that I have personally is that in these heavy clay soils that really shrink and swell, create big cracks in summer, we do have the risk.
33:14
We’ve seen manure go to drain tile from surface applications.
33:19
We’ve seen it get into the aquifer down 17 feet in Dodge County through surface applications.
33:25
There’s the suspected connection.
33:27
It’s not proven between manure irrigation with a 360 and associated fish kills in northeast Wisconsin.
33:35
We need to manage things appropriately.
33:37
You’re exactly right.
33:38
I think all of these tools, whether it’s soil health, drainage, the Rain 360 have their right fit, but we have to make sure we’re considering the field, the compaction in the soil, the soil moisture conditions, and there’s not a silver bullet solution.
33:56
Soil health may fix some problems but may cause others.
34:00
The Rain 360 solves a big compaction issue, but may cause other problems.
34:06
So anytime we’re looking at making a management change, we need to be thinking about what those possible unintended consequences may be and thinking holistically, not this is a silver bullet solution that’s going to save me a lot of time and money.
Mallika Nocco
34:23
I don’t know, hopefully that kind of gave a nice picture.
34:27
Thanks, Kevin.
34:28
I don’t have a rebuttal.
34:33
Yeah, no, I don’t, yeah,
Steven Hall
As the third pillar here, I would like to advocate for controlled drainage.
34:38
So having a structure right at your outlet where you can raise and lower stop logs is really can help, you know, mediate some of these factors, right, allowing you some control over your soil moisture to avoid sort of the shrink dynamic we have in these expansive clays.
34:53
So I think there’s some strategic ways, but I think they’re really the question to answer is what drainage coefficient do you want and what’s optimal for the system?
35:01
And really thinking not yes, no drainage, but how much and where?
35:05
And because it’s expensive too, right?
35:07
So not a trivial decision.
Mallika Nocco
35:09
And actually, Steven brings up a really good point about the timing, right?
35:13
So that if you have a controlled drainage structure this can actually time when your drainage, when you want to have that tile drainage to be operational for you, then maybe you can optimize it so it’s not at the time when you’re creating like a super highway of manure to streams.
35:32
So yeah, that’s a great, great point!
35:35
So infiltration and also I like the point that was made about how infiltration, I presented it as a great friend, but it could also turn against you, right?
35:44
If you have infiltration plus drainage, that can be a super, super highway, right?
35:49
So definitely some really great points made!
35:51
Any other questions?
Kevin Erb
Not a rebuttal, just one thing that’s not on the spinners on your table, Extension.
35:58
We’ll be doing our annual drainage workshop for farmers and drainage contractors in February.
36:03
I don’t have the date set yet.
36:05
I’m trying to find an expert on solar lift stations because that’s something that we’re seeing a lot of interest in right now.
36:11
The other thing is Extension has just for the first time in 30 years updated the list of drainage contractors available in the state and that is available online.
Mallika Nocco
36:21
Awesome, thanks and these workshops are fantastic!
36:24
Definitely if someone is like thinking about it, wants to learn more, wants to think more about the conservation aspects and control, highly recommend a drainage workshop.
Data, Insecticides, and Indirect Effects
Dr. Emily Bick, assistant professor and extension specialist, UW–Madison Department of Entomology
Dr. Emily Bick, assistant professor and extension field and forage crop entomology specialist, UW–Madison, shares research insights on insecticide use, resistance trends, and indirect ecological effects in field and forage crops. This presentation covers corn rootworm biology, BT and RNAi trait performance, and strategies to manage resistance through crop rotation and trait diversification. Emily also discusses corn earworm resistance screening, pyrethroid efficacy concerns, and aphid control in alfalfa. The session concludes with findings on how neonicotinoid seed treatments impact natural enemy communities and slug damage in conservation cropping systems. Learn practical recommendations for integrated pest management and sustainable insect control.
Transcript
0:05
All mic’d up here.
0:05
Hello everyone at the end of the day, so I hope you all stay with me over here.
0:11
Thanks for that lovely introduction.
0:13
I’m Emily.
0:14
I’m a, gosh, an entomologist.
0:16
So really I think about bugs, right?
0:19
All, all of the insects and all of the different cropping systems.
0:23
I fell under the title precision pest ecology, which basically just means how do we time and space different interventions in agriculture.
0:32
But I am the extension specialist for field and forage crops.
0:36
And now since this is the start of my fourth year here, I actually have something pretty exciting to share.
0:42
I’m going to talk about data.
0:43
I’m going to talk about insecticides, and I’m also going to talk about something called indirect effects or what is what happens when we put insecticides on our seed?
0:54
How does that impact our natural enemy community?
0:57
So this is all data that’s coming out of my lab that we did a a great number of collaborations to make this happen.
1:03
So excited to share this work with you.
1:06
I’m always going to start with corn rootworm because this is the billion dollar bug.
1:11
This is actually a $2 billion problem across the North Central region.
1:16
So if you have any corn rootworm questions, I mostly focus on corn rootworm.
1:22
I’m then going to transfer and transition into corn earworm.
1:26
And I’m just going to ask really quickly, who here grows sweet corn?
1:32
OK, some some growers out there.
1:34
So I’ve got some really fun bad news for you guys about sweet corn with corn earworm.
1:39
We did some insecticide resistant screening.
1:42
So I’m going to talk a little bit about that as well.
1:45
And then the final thing or the next two things I’m going to talk about are aphids on alfalfa, specifically pea aphids, and looking at which insecticides, which active ingredients work really well, which ones don’t work as well anymore.
1:59
And then finally, I’ll end up talking about that seed treatment and the impact on natural enemies.
2:05
Now all of this work is in process.
2:07
It’s multi year.
2:08
So keep in mind that all this stuff is preliminary results.
2:13
And before I dive in to this kind of data, insecticides, indirect effects talk, I would have put a little bit of an advertisement out there, but it has to do with insects.
2:25
Timing matters more than anything else, right?
2:28
When the insect physically shows up in your field.
2:31
So following one of the states, following Iowa State University, we initiated an insect pest text alert system, which last year had about 400 folks on that list where up to once a week over the growing season.
2:47
I think we sent all of 6 texts out last year.
2:50
We sent a really good, hey, heads up, this is what’s going on in your part of the state.
2:56
This is the insect that you should be scouting for.
2:59
And while the first year that we had this two years ago, there weren’t that many large insect issues, last year we had true armyworm.
3:07
That second generation of true armyworm come around and it devastated a whole range of grasses, not just corn, but a whole range of forage grasses as well.
3:18
And the folks that were on this listserv were able to get that early warning, were able to get that, hey, heads up, this plague of locust style insect true armyworm was sweeping through the state and hopefully that allowed them to respond in a really timely manner.
3:35
So you can really easily find it.
3:37
You can search insect pest text alert or pest alert on the crops and soils website.
3:45
Let’s see.
3:47
OK, now we’re going back to my favorite insect over here.
3:50
We’re talking about corn rootworm.
3:52
When we think about corn rootworm, we’re actually thinking about 3 different species of insects.
3:58
They all fall under the Diabrotica species or Diabrotica genus.
4:02
They’re three different species.
4:04
There’s actually a fourth.
4:05
There’s a Mexican corn rootworm, but it only makes it as far north as Texas, and we really care about two of these three primarily.
4:13
Well, southern corn rootworm, which is the spotted looking insect.
4:17
It’s also called the spotted cucumber beetle because it eats lots of things, but it also exists in our area.
4:22
It caused about 10% of the corn rootworm damage.
4:25
We’re really trying to think about northern and western corn rootworm.
4:29
These are insects that are pretty small.
4:32
The northern is that bright green color.
4:34
The western has this yellow and stripes.
4:36
The black head and these insects, well, you might see them flying around your field mid August or so.
4:43
Really you’re going to run into them earlier in the season because of their biology.
4:48
So when we’re talking about western and northern corn rootworms, we know that there’s really no rescue treatment, but at the same time, it’s the immatures that are causing the damage.
5:00
It’s that first through third instar.
5:02
So we really need to understand the life cycle of these corn rootworm insects.
5:08
Well, First off, eggs are laid and they overwinter in corn.
5:12
So when you see those little green adult beetles or the little striped, striped yellow and black adult beetles flying around the field, that kind of mid August to mid-september time period, that’s when they’re mating and when they’re laying their eggs.
5:29
One thing that’s good to understand is these insects have kind of cracked the code for the fact that we rotate our crops.
5:39
Western corn rootworm will readily lay its eggs in other crops.
5:43
So think about eggs in soybean crops or alfalfa crops as a way to kind of break that rotation resistance.
5:51
And northern corn rootworm will occasionally lay their eggs in other crops.
5:57
The larva start becoming a problem mid June.
6:00
This is primarily driven by soil temperature and it has to do with them feeding on the roots.
6:05
Starting around that June 15th time period and all the way through about August 15th.
6:13
We do our root dig right when the the larva are at their largest stage, right about around that July 10th, and once again then we cycle back the the larvae will then pupate in the soil.
6:26
They’ll then emerge as adults kind of starting early August.
6:31
Most eggs are laid after that August 15th date because these are sexually reproducing organisms.
6:38
And while the adults will do a little bit of damage, they can feed on silks, they can reduce kernel set.
6:44
Mostly they are not the problem, it’s mostly the fact that they’re running around laying eggs.
6:51
Now, some folks have raised the idea of spraying those adults as kind of a control for next season, but really the evidence hasn’t suggested that so far.
7:02
We will be going through and testing that and I’ll talk about that in a little bit.
7:07
It’s also really good to understand how the resistance is happening, right?
7:11
So there are BT traits that are able to control corn rootworm and they control it at that larval stage.
7:20
Really the only time that you can impact that population is by the choices you make at planting.
7:27
You can put an inferro insecticide, right like force, like bifenthrin.
7:33
You can use a BT trait.
7:36
One thing to know is that BT hybrids really only confer a moderate dose of poison, which means you actually need more than one.
7:46
And while there are four BT proteins available, there’s actually a new RNAI protein that seems to work really well.
7:53
Three of them have something called cross resistance.
7:57
Cross resistance is really interesting because basically the same strategy that a corn rootworm uses to stop itself from being susceptible from BT, right?
8:11
BT is eaten by the corn rootworm larvae.
8:14
It then punches a hole in the gut when the larvae learns how or evolves the ability to stop that right?
8:21
It either processes it or the metabolisms are a little bit faster, or it literally pushes the the protein through it through its stomach a little bit faster.
8:29
That actually confers resistance to three of the four other proteins.
8:35
I know this slide says that there’s no fitness cost it there actually is a fitness cost.
8:40
So resistance is dominant, which means that it only takes one of those two alleles to be resistant for that resistance to show up.
8:50
But because there’s a fitness cost that means that when we rotate your field out of corn after, let’s let’s call it, I think it’s four years, then your trait, your population is going to go back to the non resistant part, which means that your population will literally go back to being susceptible to those traits.
9:12
So fundamentally, that means that if you plant the same hybrids year after year after year, with the same traits year after year, the same insecticides year after year, it’s going to be a huge issue because you’re essentially growing resistance in your own field.
9:26
However, if you’re rotating through, let’s call it soybeans and then BT trait and then the RNAI trait and then the inferro, and you go back to soybeans the next year hypothetically, or soybeans every other year, you can actually stop resistance in its tracks that way.
9:43
Now, we talked a little bit about this crop rotation resistance from the western corn rootworm laying its eggs in other fields, but the northern corn rootworm actually evolved a slightly different strategy.
9:56
It evolved the ability to have a longer diapause or really egg hibernation.
10:02
Which means that instead of hatching after one winter, the northern corn rootworm eggs can hatch up to four years after they are laid.
10:11
No, that that sounds like it’s a really, really big issue.
10:16
However, do know that every year that the eggs are in the field, there’s more likely that something’s going to happen.
10:22
There’s more likely that they’re not going to be viable the year they’re supposed to be hatched.
10:27
There’s more likely that they’re going to be predated on that they’re going to be punctured, they’re going to desiccate, right?
10:33
Something could happen.
10:34
So even though that has this, this new type of rotation resistance that longer diopause or hibernation, the longer the eggs are in the soil, the less likely they’re going to be viable and the lower your populations are going to be.
10:49
I should also note that there’s some insecticide resistance that’s been documented, especially in neonics, which means that this seed treatments just don’t work as well.
10:59
Oh, that’s a great question.
11:01
Is there, have I, do I have any thoughts on resistance to RNAI?
11:06
Well, I can tell you that I tested RNAI out and I’ve tested it the last two years and it works really, really well.
11:13
Well, I haven’t looked at the research on resistance to RNAI since it’s new, it’s a relatively new thing.
11:20
It’s not surprising that insects are able to build resistance to even new strategies, right?
11:26
Even trying to interrupt their their DNA replication, which is essentially what RNAI is doing.
11:33
So in this case, what I would recommend is if you’re having some trait failure, I would recommend rotating through different traits.
11:43
And if you have the ability to put in furrow insecticides in the ground, they’re actually a number of in furrow insecticides that work really well, right?
11:51
Force Evo, bifenthrin, all work really, really well.
11:55
And since it takes about four years to take a trait out of the system, right for that resistance to go away, I would just try to rotate on that four year basis.
12:06
So we, we looked at a couple different things out in the field and this is the the root node ratings, which is basically my lab going out and digging up representative samples on I think it was 20 different plants for each of the treatments spread kind of randomly blocked across the field.
12:26
We looked at the control, we looked at smart stacks, the smart stacks plus the RNAI trait and just the RNAI trait.
12:34
And this is the challenge when you have something like smart stacks plus that RNAI trait, you’re essentially keeping that resistance in your population.
12:42
You’re keeping the your foot on the gas pedal, right?
12:46
You’re making sure that that population stays resistant to your BT traits, which is why I would recommend to try to avoid resistance.
12:54
Keep in mind this is a field that’s been grown and continuous corn pretty much for 20 years.
12:59
This is what Brian Jensen was a had set up for us, right?
13:02
So we have a really, really high corn rootworm population, and it’s not surprising we have some resistance in this field since we’ve been testing these traits and these inferos on this population year after year after year.
13:14
I would recommend trying to rotate through.
13:16
I would recommend trying the RNAI treat one year, the next year, even in the neighboring fields, if you’re rotating across your farm, try that Smart stacks.
13:26
The next year, I would go to something like an in furrow insecticide.
13:30
And then by the time your 4 rolls around, your population is likely significantly less resistant to the first thing you tried.
13:38
Even if you developed resistance, it will then kind of digress, right?
13:43
There’s, there’s a fitness cost.
13:44
The insect just can’t build resistance without losing something along the way.
13:52
So that was kind of our, our early stages, our checking what’s going on with the traits.
13:58
And once again, I’m not the first person to report these types of results, but one of the big questions I get is on adult spraying, right?
14:07
It is I think a, a biological need for people.
14:11
As soon as you see an insect, you want to squash it, right?
14:13
I dealt with this when I was working in California and every single insect that you see flying around the field, you’re like, Oh my goodness, we can, we can get those ones, but we actually don’t care about individual insects.
14:25
We care about the effect of entire population of insects on your population of plants, right?
14:32
So we care about that aggregated effect.
14:34
And well, adults, if you hit the timing right, they might clip the silks, they might cause some pollination issues.
14:42
Mostly they’re just, they’re just flying around laying eggs, right?
14:48
That’s their primary function.
14:49
They’re not feeding as much as these larvae are feeding, which means that if you if folks are asking to spraying the adults actually reduce the number of eggs in the population.
15:02
Well, that’s a really good question.
15:04
We looked at some some sister states and everyone is kind of coming up with a no spraying the adults unless you do it in an area wide, unless all of your neighbors, you and all of your neighbors within a 20 mile area are doing this, this, this process, it’s probably not going to be able to reduce the number of eggs.
15:21
However, we wanted to try it out and we wanted to try it out in a couple different ways.
15:27
So we set up this field and this is at Arlington Research Station.
15:31
This is the blue barn.
15:32
It’s the Entomology building.
15:33
It’s not blue.
15:34
I think it was at some point this entomology building.
15:37
We have this continuous cornfield that’s been going on adjacent to it.
15:42
We took the northern 3 acres and we said we’re, we’re only going to care about these north and three acres.
15:49
We then split this area in half.
15:51
Well, technically we split it in quarters, but we, we basically we quartered this area and on one side we had traded and untraded, untraded and traded.
16:00
We used the Smart Stacks Pro, so the Smart Stacks plus RNA I and then we went out when adults were flying about a week after the kind of peak flight, we started spraying them, right?
16:11
We, we did one spray and then we followed this for the five following weeks and actually saw that our spray really, really worked in just the areas that we had sprayed, right.
16:22
So we had these, these little yellow dots or squares represent yellow sticky cards, actually counted the number of beetles on each of these sticky cards and saw that the spray worked.
16:34
In this case, we used bifenthrin.
16:36
Now what we’re going to be going to do next year is take a look at this area that we sprayed and we didn’t spray, that we had treated and untreated.
16:44
And we’re going to essentially have little transects within this area where we will go and dig roots, 5 plants per each of these lines.
16:55
Each of the lines represents 4 rows, right?
16:58
We’re going to dig the roots and we’re actually going to pressure wash them and give them a root rating and evaluate and see are there less larvae in this area.
17:07
We’re also probably going to take some soil samples and check are there actually less eggs in the soil at each of these spots.
17:15
And hopefully we can come up with a a really good answer for you guys about whether or not spraying adults is an effective way to reduce the number of eggs in your field that that overwinter and then thus reduce that larval number.
17:31
OK.
17:32
Next we’re going to talk about corn earworm.
17:34
We’re talking about corn earworm where you’re primarily talking to the sweet corn growers in the room.
17:40
Corn earworm is an insect called Helicoverpa zea.
17:44
It actually feeds on a lot of different things, right?
17:47
This, this insect, it, it flies up up north.
17:49
There’s a population that lives in Texas.
17:51
There’s a population that lives in Florida.
17:53
We’ve actually not us, but some of our, our colleagues have screened our population.
17:58
We get the Texas ones or these insects feeding not just on sweet corn, but it’s also called cotton bollworm.
18:04
It’s also, there’s a, a tomato name for it as well.
18:07
They feed in lots of different crops.
18:09
They get exposed to lots of different insecticides.
18:12
And as the generations cycle through, they move further and further north until they eventually hit us in Wisconsin, which means that, you know, our local population, if it’s resistant to something, it’s not our fault necessarily, right?
18:27
It is much more likely that it’s the fault of our our southern neighbors.
18:32
And there’s not much that we can do about that.
18:35
So this insect, it actually comes in a lot of different colors.
18:38
It is one of the the grosser insects.
18:40
And this is coming from an entomologist over here, right where if you’re shucking corn and you, you see something that has 3 or 4 black stripes in the back and a light colored head capsule over here, that’s likely to be a corn earworm.
18:53
You can see some pictures.
18:54
We’ve got some guides online about it.
18:57
What we did was we joined a group of 24 states.
19:01
This is let out of led by a guy Galen out of out of University of Maryland.
19:06
He’s actually emeritus.
19:07
So it’s kind of amazing that he leads the study year after year.
19:10
And he set up something called a Sentinel trapping network or Sentinel cropping network, where we basically planted the same 2 varieties of corn.
19:20
And these are varieties that are pretty much genetically identical except for one has two of those BT traits, a Cry1Ab and the Vip3A protein.
19:30
And the other one just doesn’t.
19:32
And what we were doing is we were screening to see how well were our BT traits holding up not just across Wisconsin, but across a 24 state region, pretty much the the northern 24 states in the contiguous US.
19:47
So and we’ll have the aggregated results and that’ll be written up in a report.
19:51
But looking at our study, we actually went and shucked 100 years of corn from each of these varieties.
19:58
These were planted adjacent to each other in the southern part of that field that we ran the spray trial in.
20:04
And we found that the the crop that had no traits had 31% clean ears, or literally just 31 clean ears.
20:14
Out of the 100 that we shocked compared to the traded crop which had 83% clean ears, clean ears are no insects in those whatsoever.
20:23
And even though we were targeting corn earworm, we also hand ID’d absolutely everything that was an ear pest in those.
20:31
So, so far the trait seems to work.
20:34
The trait combination seems to work for the untreated crop the the Providence.
20:41
There were 83 corn earworms in the 100 years that we shocked versus the traded only had 17.
20:47
And then something really interesting happened when we broke it down by instar as in what life stage is the insect in.
20:56
We saw this really interesting distribution where not only were there fewer in the traded population versus the untraded, they were actually a much younger life stages.
21:09
That has to do with the fact that as the insect will go along and it will munch, it’ll go along, it’ll munch.
21:15
It gets a little bit of a bellyache, right?
21:17
The BT trait, it physically punches a hole in the gut, right?
21:22
That’s what BT does.
21:22
It actually puts a hole in the gut lining for an insect and that means that the insect is just not feeding at the rate that would cause the next molting stage.
21:35
You can actually measure the head capsules and measure the insect length and get a really accurate level of what instar is this insect in.
21:43
So not only were there significantly more corn, corn earworm larva in these ears, but they were actually at an older life stage than what we what we would see without the BT OK.
21:57
So then last year I had some calls, I had some calls about pyrethroid failure, pyrethroid efficacy failure.
22:06
If you’re not putting out traits, if you’re growing either organic or you don’t have BT traded corn, which which good news still seems to hold up really, really well in our state.
22:16
You’re often times spraying 3 times during soaking or once a week during silking to essentially stop those larvae from eating the silks and getting into the ear.
22:28
And you’re spraying right around the, the mass flight.
22:31
If the flight of the corn ear worm lines up with the, with the timing of your silking, that’s the best way to protect.
22:38
And one of the best active ingredients that we have are a whole range of pyrethroids.
22:43
Now in three different sites in southern Wisconsin, we evaluated whether a gene for pyrethroid resistance was in our population.
22:53
And this is actually a little bit of a story.
22:56
So there’s an insect called Old World bollworm.
23:00
Instead of being a Helicoverpa zea, which is the insect corn earworm, it’s Helicoverpa armigera, right?
23:09
I this is essentially an identical insect or a near identical insect.
23:13
You physically looking at the two species side by side cannot tell them apart.
23:18
That has developed in Europe versus developing in the US.
23:23
And it was reported here about a decade ago in it was actually reported just outside of Chicago.
23:30
And we were really concerned, right?
23:32
The entomologist community was extremely worried that this insect would be the next invasive insect.
23:37
It would kind of sweep through.
23:38
It would cause this massive issue across many different cropping systems, not just in sweet corn.
23:45
But it didn’t do that.
23:46
It kind of disappeared.
23:48
And we’ve been looking, we’ve been screening using the Department of Ag, Trade and Consumer Protection.
23:52
They’ve got a, a pheromone trapping network.
23:54
They actually screen a number of those insects that come in year after year.
23:58
And we haven’t found the full genome of that insect.
24:02
We actually haven’t found Old World bollworm in the state of Wisconsin.
24:07
However, in Florida and also in kind of the Denver ish, Colorado region just South of Denver where they grow a heck of a lot of sweet corn, they figured out that it wasn’t that the insect took off.
24:20
It actually made it into the system of corn earworm.
24:25
So it actually handed off it.
24:26
It kind of was completely swallowed by our corn earworm population and it handed off a specific gene, which is cyp337b3.
24:38
And that gene unfortunately confers resistance to pyrethroid.
24:43
So when we were looking, when we were screening these, these populations of insects that come out of a sprayed corn earworm field, we’re screening them for this particular Old World bollworm resistance gene.
24:57
And we found in every all three of the populations that we looked at, we looked at moths, we looked at the immatures, over 87% of those insects had the old world bollworm gene.
25:11
So this is the first time this has been reported in Wisconsin.
25:14
It’s not the first time that there’s been a pyrethroid efficacy failure.
25:18
Actually for the folks that grow grow sweet corn, how many of you guys are are spraying with pyrethroids during that silking.
25:28
Yeah.
25:28
OK.
25:29
So some of you, some of you, not all of you are. Are the rest of you guys using traits or just corn earworm’s
25:34
Not a huge deal?
25:36
Yeah, that’s fair.
25:37
You can also change the timing of of planting, right.
25:41
If you plant a little bit earlier, you can miss the corn of your worm flights and us kind of get get out of the area.
25:48
So we worked with one of our colleagues who’s actually a USDA ARS scientist out of Iowa.
25:55
He’s in Ames and Doctor Brad Coates is a genetics person, which is good because I am definitely not a genetics person.
26:02
I like being in the fields.
26:04
I like being out there sampling.
26:05
I like thinking about these populations rather than thinking about what population genes are going on.
26:11
And he was able to to run all of these gels for us.
26:15
And you can kind of see it over here in green where you get that really strong bar over here.
26:19
And over here, if it’s bright white, that is where the resistance gene is.
26:25
If it is essentially absent over here, then you don’t have a resistance gene.
26:30
And if you kind of have a lighter color over there like these three, that’s when you have a partial resistance gene, right?
26:38
It’s a little bit ambiguous.
26:41
So what are we doing next year?
26:42
Well, we’re going to be working with a heck of a lot more growers.
26:45
We’re going to be kind of spinning up the engines and we’re going to be mass screening across Wisconsin.
26:50
Keep in mind, the insects that we screened were in three separate fields, three separate farms, I should say, where pyrethroids had been sprayed.
27:00
And also the insects then survived the sprays, right?
27:04
So we’ve already selected for the ones that can survive pyrethroid, which is why it’s not super, super surprising that we had this resistance gene.
27:13
So what we’re going to be doing next year is actually looking at a whole bunch of different farms across the state of Wisconsin before all the spraying.
27:20
So this is during the moth flights prior to prior to spraying events and collecting those moths, sending them to Brad and doing another screening event, seeing what our problem really is.
27:33
So that was the bad news of the day.
27:36
Next I want to talk about aphids on alfalfa.
27:39
And when we think about aphids, we’re usually thinking about pea aphids on alfalfa, right?
27:45
So these guys, they’re like green.
27:47
They’ve got these dark banded antenna.
27:49
They’ve got a black tip cornicle, which is the little structures off of the back of the abdomen that helped collect that honeydew.
27:56
Generally speaking, aphids are both asexual and sexual, which is great because asexual insects are much more susceptible to specific insecticides, right?
28:07
There’s less variance in the population, and it’s more likely that you can target them.
28:12
However, because they’re asexual as well, it means the populations can just ramp up out of nowhere and really, really surprise you.
28:21
So what we did was we we looked at these insects that have these piercing, sucking mouth parts that essentially cause reduced plant vigor.
28:29
If it gets really, really bad in alfalfa, it causes kind of this yellowing of the alfalfa plant.
28:34
And we took a look and we asked which insecticides were effective for these.
28:40
And we sprayed right when the population started booming.
28:44
And then we actually looked once a week for a couple weeks thereafter until it was time to cut the alfalfa.
28:50
This was the the second cutting, at which point we couldn’t look at our aphid population anymore because they weren’t physically there.
28:58
And that’s a really good reminder where if you have, if you’re within seven days of a cutting for alfalfa and you see a massive insect outbreak, often times you can do the cultural control effort.
29:11
You can actually just go ahead and cut a little bit early and that should wipe your field clean, really reduce that insect population.
29:19
So in this case, we tested against the industry standard, which is dimethylate with one of the permethrin insecticides out there.
29:30
We also looked at different rates of indoxacarb, which was ineffective by itself, but worked really, really well with flonicamidon there as well.
29:41
And then we looked at just a range of these treatments and it turned out we still have pretty good efficacy for everything except for indoxacarb on aphids.
29:51
Now keep in mind, we’re doing this.
29:52
This is a replicated block study, but we’re doing this in one site at Arlington Research Station and your population might look a little bit different.
30:01
Well, if it’s do move, they during their kind of when they get too crowded, they’ll actually grow wings and they’ll go and fly off into the air.
30:09
They and they’ll, they’ll kind of find you each year.
30:13
It might be a little bit different year after year.
30:15
So keep keep your scouting hats on and make sure you keep doing those sweeps.
30:22
OK.
30:22
The final part of the talk, and I know I’m getting close to over time so I’m going to go a little bit quickly here is on kind of indirect effects of that seed treatment.
30:33
Often times we in fact pretty much across the board, especially in soybeans, especially in corn, it’s really difficult to get non insecticided seed or naked seed.
30:45
And that’s because mostly, well when it comes to corn we’re really concerned about things like seed, corn maggot.
30:52
When it comes to soybeans, we’re really concerned about the insects that would feed right away on the soybeans.
30:59
And this actually came out of a study with some conservation croppings of system farmers that were really focused on slug damage.
31:08
So two years ago we had a big, pretty large slug population and it decimated some of these conservations from the no till, some of the cover crop systems, right, where we’ve done everything that we could for the soil and we just made it into a really lovely environment for slugs, right.
31:25
Who here has had slug issues?
31:27
OK, I’m seeing so.
31:28
Oh my goodness, lots of hands go up.
31:30
Excellent.
31:30
OK, so you’re the right crowd for this one.
31:32
So we were looking at this and we’re hoping, we’re hoping to actually have a second year of data next year on our like slug net project.
31:42
But we last year looked at 7 different sites and I should say it was it was my group, but it’s also Dane Elmquist, who’s our conservation cropping specialist.
31:50
Laura Flandermeyer helped out with this as well as Jordan Kampa.
31:54
And the first thing we did is we we compared a number of different treatments, but one of the treatments we compared was whether a seed had a neonicotinoid seed treatment or that insecticide seed treatment on it or not.
32:07
And right away the number of soybean plants that emerged was neon identical whether it had the insecticide on the seed or it didn’t.
32:16
But as soon as we started looking at things like slug damage, we saw a third of the of the essentially a 66% drop in slug damage when there was no insecticide on the seed, which is weird, right?
32:32
The slugs, they’re not insects.
32:34
I’m a little bit surprised that I’m working on slugs, right?
32:37
Not in my training.
32:38
They’re mollusks, but there’s something going on here where when you have this insecticide on the seed, you actually have more slug damage.
32:46
And then we looked at not just slug damage, but leaf damage in general at these seven farms, and we found identical trends.
32:54
There was three times more damage, leaf damage on the plants that had the insecticide that should have been or is meant to protect those plants from the leaf feeding insects early on.
33:06
This is all within.
33:08
This is all early, early stage work.
33:12
OK, so then we dig, dug in a little bit.
33:14
We’re like, what is going on?
33:15
And one of the things we decided to focus on is something called ground beetles.
33:20
These ground beetles are they fall into the the family gravity.
33:23
It’s actually the largest family of insects in general.
33:26
It’s a huge, huge diversity of insects.
33:29
And these are massive predators, right?
33:31
Many, many, many different types of species and well, we looked at those ground beetles.
33:36
We also looked at things like harvestmen, which are Opiliones or daddy long legs, other term for them.
33:42
They also looked at spiders.
33:43
And I’m going to start with those two elements.
33:46
There was no difference in the spiders or the harvestmen slash daddy long legs, which are also predators.
33:53
They seem to be unaffected if a seed had an insecticide on it or not.
33:58
But as soon as we looked at ground beetles, there was a 50% reduction across the board of number of morpho species or the number of species that were there in the field as well as the number of individuals.
34:11
So that means the diversity of your natural predators that are doing a lot of that pest control for you just dropped in half as well as the numbers that were out there.
34:21
And we saw this not just because we went out, we sampled a lot.
34:24
We actually they had these things called pitfall traps.
34:27
So we dug a hole in the field, we dropped a bucket in, put some ethanol.
34:30
And then I still have students finishing up this week.
34:32
Hope that hand ID’d every single insect and spider that was in that bucket.
34:39
OK, so this is first year work.
34:41
No one’s actually ever looked at slugs in the state of Wisconsin.
34:44
So we’re going to repeat this next year.
34:46
We asked the North Central SARE group to to fund it a little bit more because we were kind of just doing this for kicks.
34:53
But we think that this might be part of the story of what’s going on and why slugs have been such an issue in conservation cropping systems.
35:04
Anyhue, I want to open this up to any questions.
35:06
I know I threw a lot of data out there and I went about 5 minutes over.
35:10
So I’m sorry, Anne, for for going over there.
35:13
Are there any questions?
35:17
Yeah.
35:17
OK.
35:17
So what’s going on?
35:18
Let’s let’s dig in a little bit deeper.
35:20
And that’s a great question there.
35:21
It’s well, I’m not sure if it’s because the slugs are eating the plants and then holding those neonicotinoids, but it’s certainly because all the food source, the entire the entire foods.
35:32
Whoa, I know I’ve messed this up.
35:34
I’ll drop this over here.
35:35
The entire food chain of insects that are herbivores on plants that are feeding on the plants will eat the the insecticide either get a full dose and die or partial dose and not die and kind of keep living.
35:48
And then the predators will feed on those and the predators, ground beetles, massive, massive predators are also insects.
35:56
And that insecticide is then found in the ground beetles.
35:59
So I’m not sure if it’s directly because of the slugs, but it’s definitely because of the the insects feeding on there.
36:06
So it’s it’s a whole, whole chain.
36:08
Yeah, please.
36:13
As in you put more insecticide on the seed and the plant performed better.
36:18
Yeah.
36:18
Yeah.
36:18
That, that doesn’t surprise me at all, right.
36:21
Because a lot of the a lot of the yield issues for for plants are insects, right?
36:26
For for crops or insects.
36:29
Yeah, yeah, and it and it’s great.
36:30
It’s a general insecticide.
36:32
It is not quite non-toxic, but pretty close to non-toxic for mammals, right.
36:37
The off target effects are pretty good.
36:39
It breaks down in sunlight.
36:41
So neonics in general are to, to me, a great option.
36:47
Yeah.
36:48
Yeah.
36:48
So they in California and in New York, they’ve actually banned seed treatments.
36:53
So I’m guessing it’s going to be more of an option in the future to at least have access to naked seeds.
36:58
Because right now we were trying to figure out ways to pull that seed treatment off the seed.
37:03
And it was, we need to go to some really specialty locations, even buy seed that didn’t have that seed treatment on it.
37:12
Oh, I’m sure, I’m sure different formulations works differently.
37:15
That doesn’t surprise me at all.
37:17
However, I do want to say that we’ve talked to Damon Smith and he basically said that it’s really good that you have that pathogen protection, right, That fungicide on the seed.
37:26
It still makes economic sense in that case.
37:28
Now I’m presenting data from 7 fields across kind of the the central eastern part of Wisconsin.
37:35
It’s not across the entire state.
37:37
We’re hoping to expand this work and we also only have a single year of work out there.
37:42
But it’s something worth keeping in mind, especially a slug start as you adopt more conservation cropping practices, right?
37:49
You’re making the systems that you’re working in more hospitable, the slugs and you’re just, you know, we’re we’re kind of knocking down some of our natural enemies just with our business as usual.
38:01
So it might be one of those things that it’s worth tweaking on.
38:04
I should also say the data we presented is on sweet beans.
38:07
We’re going to look at corn next year as well.
38:11
Cool.
38:11
Any more, any more questions?
38:14
Well, thank you guys.
38:15
Appreciate it.
Wisconsin Corn and Soybean Weed Management Updates and Considerations for 2026 and Beyond
Dr. Rodrigo Werle, associate professor and extension cropping systems weed scientist, UW–Madison Department of Plant and Agroecosystem Sciences
Dr. Rodrigo Werle, associate professor and extension weed scientist, UW–Madison, shares the latest updates and future considerations for corn and soybean weed management in Wisconsin. This presentation covers herbicide resistance trends in waterhemp, including newly confirmed cases of HPPD and S-metolachlor resistance, and emphasizes the importance of residual herbicides and strategic tank mixes for consistent control. Rodrigo also introduces upcoming technologies like Vyconic soybeans and new herbicide products, discusses integrated weed management strategies such as planting green with cover crops, and highlights practical recommendations for 2026 and beyond.
Transcript
0:06
Thank you, Scott.
0:07
Good afternoon.
0:09
All right, folks.
0:10
So for those of you that don’t know me, Rodrigo Werle, Extension weed scientist.
0:14
Like Scott said, I’ve been here in Wisconsin since 2018.
0:18
OK, so wrapping up here, another beautiful season.
0:22
I really love this time of the year, just looking back and trying to process everything that we have learned through our trials, but also in communications with you all.
0:32
And then also time to start thinking about next year already, right?
0:36
And that’s my goal here.
0:37
I’ll present some of the exciting findings that we have that will hopefully help you and your clients battle some of the weeds that we’re dealing with out there.
0:47
But this is also the time where I really take in your questions and your your questions for me usually become research projects next year.
0:55
OK?
0:55
So please do ask questions because they help us a lot.
0:59
So hopefully we do relevant research for you guys.
1:02
So today I’m going to be focusing on corn and soybean weed management, some of the updates that I have for you guys and also considerations focusing 2026, but also beyond.
1:12
There’s going to be a lot of stuff coming down the pipeline.
1:17
There’s a lot of exciting things coming down the pipelines.
1:20
There’s also some concerning things coming down the pipeline if we don’t use them properly, right.
1:25
Jake, you and I already having a conversation on that a little bit ago here.
1:29
So let’s let’s just let’s talk about that today, OK, So like Scott said, I love putting pictures of my group.
1:36
The reason why I do that is because if if I if I don’t work with them, I’m not here, all right?
1:40
They’re the ones that do all the work that I’m gonna be presenting here today.
1:44
And I am truly blessed to work with these amazing people here.
1:48
OK?
1:48
So they do tremendous work throughout the year.
1:52
Right now, in about 10 days from now, we’re heading to Michigan to our big conference.
1:56
So all this people here are summarizing their data and they’re sending me their data right now so we can put posters and talks together.
2:03
So this time of the year is kind of it’s, it’s overwhelming and fun and exciting because then you got to travel around the state on the call.
2:09
They’re like reviewing posters, you know, all at the same time.
2:12
So it’s a lot of fun.
2:13
But where I’m going with this, they’re sending me a lot of data.
2:16
And then with that, I have a hard time on what I can put on this talk.
2:19
So hopefully you’re ready to be here until 4:00 because I got a lot of stuff to share with you all today and us because of their great work.
2:26
I also want to thank our sponsors.
2:29
Without their sponsorship we cannot do the work that we do.
2:32
The only thing that’s guaranteed in this picture here is my salary.
2:35
The rest we need to find sponsorship for.
2:37
Just to clarify that cuz some people don’t understand how we run our businesses right?
2:42
So as faculty at UW, we got a salary and an office and we gotta go fight for the rest.
2:47
So we need the sponsorship in order to do the work for you all.
2:52
And on behalf of our team, our extension team, we really want to thank you guys for one being here and for supporting us.
2:59
OK, so thank you all.
3:01
All right, so this is my outline for today.
3:04
I know I’m going to struggle to cover it all, but we will do our best.
3:07
The first part here, I’m going to give you an update on water hemp resistance.
3:11
Then I’m going to discuss some of the new traits that are coming down the pipeline and some of the potential products that we should soon have available in our portfolios.
3:21
I want to discuss herbicide tank mixes.
3:23
Today we’ve been talking a lot about tank mixes, but we have spent a lot of time talking about tank mixes from a pre emergent standpoint.
3:32
And if you’re thinking water hemp post emergence effective tank mixes is the way to go.
3:36
And I’m going to be showing you some kind of exciting think mixes, at least to me that I was not thinking about before.
3:43
But we have a new graduate student that’s looking into this and there’s there’s some excitement as far as that goes.
3:49
OK.
3:50
So think mixes are important.
3:51
And then lastly, if I have some time, I’m going to be talking about our planting green efforts for using cereal rye as part of an integrated weed management strategy in soybean cropping systems.
4:04
OK.
4:05
How many of you guys have seen this slide before a few times, who wants to present it?
4:11
OK, so I’m going to start with this slide because some of you have not seen it.
4:17
But then from this slide, I’m going to go to the next piece of the story.
4:21
So this is part of our herbicide resistance monitoring effort.
4:26
You know this effort here is sponsored by the Wisconsin Soybean Marketing Board.
4:30
So what we do and remember every time I say we somebody on that picture, OK, so when we do this effort here, this is OK.
4:38
Let me just take a step back here.
4:39
So this is work that we did back in 2018 and then we replicated this effort in 2023.
4:46
So our idea or behind this slide here is to understand how is water hemp adapting to the herbicides that we’re using in corn and soybeans.
4:56
So I have 2,4-D. have atrazine, I have dicamba, I have fomesafen or Flexstar, I have glufosinate or Liberty and I have mesotrione or Callisto, OK.
5:10
On top is the 2023 results or samples that were collecting in 2023.
5:15
On the bottom here is 2018.
5:17
OK.
5:18
So five year gap, my research question here in five years has water hemp adapted to the chemistry that we’re currently using, yes or not?
5:27
And the answer is yes, for the most part.
5:29
OK.
5:31
When Enlist Technology came online back in 2020, we would go out there and we would spray Enlist One, right?
5:39
And we would get really good control of water hemp.
5:42
Are we on the same page here?
5:44
If you go out there and if you spray straight Enlist One, what happens?
5:49
Do you get full control?
5:51
No, you twist them and they come back, right.
5:56
So that’s exactly what we’re seeing in our monitoring program.
5:58
You’re just validating that as a matter of fact, when we started doing research with enlist plots, we had all this.
6:04
We had liberty, We had enlist.
6:06
We had enlist plus liberty, and all we needed was enlist.
6:10
You Fast forward five years, we broke that already.
6:13
If you’re trying to control water hemp post emergence with straight enlist, you can’t, OK?
6:19
And this is what our data are showing here.
6:20
In five years, it took about five years for the water hemp to adapt.
6:25
So this thing is amazing, isn’t it?
6:27
I call it job security.
6:29
I love it, OK.
6:31
And the same trend is happening here for dicamba.
6:34
The yellow ones are the ones that I’m concerned about that we’re seeing an uptick.
6:38
So Flexstar, I don’t think that surprised you all, but this is the one that I’m really concerned about the mesotrione.
6:45
It’s not going up very fast yet, yet.
6:50
And I will stop there.
6:50
And I want you to hold that thought for a little bit.
6:53
All right, Rodrigo, we know this.
6:55
What else is going on?
6:57
Oh, glufosinate, It’s still working quite well.
6:59
OK, so good news here, Liberty, at least from a resistance standpoint.
7:03
We haven’t found liberty resistance in water hemp in Wisconsin yet.
7:08
States South of us have.
7:10
So it’s just a matter of time.
7:12
OK.
7:12
But Liberty is a very, very important herbicide.
7:14
It has become a very important herbicide.
7:16
And we really need to be good stewards of liberty because once we break liberty, what do we do?
7:23
OK, so we need to be good stewards of liberty or glufosinate.
7:28
OK, this is fresh.
7:31
This is the first week I’m presenting this.
7:32
So this is some work that my visiting PhD student, Luma Loueiro is leading.
7:39
OK, so here we have the latest, the newest cases of confirmed resistance.
7:46
So I’m going to go back one slide.
7:48
This thing here is messing me up.
7:50
So what we did here, we have multiple populations, a lot of populations behind this data set, OK, what we’ve done here, we selected the worst of the worst and then we decided to do some additional screening for resistance.
8:06
So today or this week is the first time that I come in front of you.
8:10
And then I say that in the state of Wisconsin, we now have water hemp populations that are resistant to Callisto or HPPD herbicides.
8:18
That is the first time that we confirm that in water hemp and we confirmed that in three different populations, OK and all three of them are from Southern Wisconsin to not very far from where we are.
8:32
OK.
8:33
So this is these are first confirmed cases of HPPD resistance or cholesterol resistance.
8:41
Does that concern you guys?
8:43
Why?
8:47
Yep.
8:48
So Callisto is one of the most important and one of the most affordable tool tools that we have for corn weed management, right?
8:56
You break that, what do we do?
8:58
OK, So this is very, very concerning.
9:01
The other piece of the puzzle is that Luma is also looking at resistance to herbicides that can be applied pre emergence.
9:09
OK.
9:11
So it’s very unfortunate.
9:12
And then this is not news because we found the population that we just published on and I was concerned this was going to be the trend.
9:18
So the worst ones that we have are also resistant to like let’s say fomesafen applied pre emergent.
9:24
So I’m not talking about spraying to emerge plants, I’m talking about spraying to the soil and then you’re losing the residual activity of the herbicide due to resistance.
9:33
So that’s that’s very concerning on the Flexstar.
9:35
But I’ve heard some people whispering already.
9:38
I think this is the problem here.
9:40
OK, so this is the second time that I come in front of you with something that I haven’t said before, which is that we now have a population that we confirm to be resistant to S-metolachlor dual applied pre emergence.
9:55
And that’s again very, very problematic because of how extensively we’re using dual or S-metolachlor in both corn and soybeans.
10:05
OK, So we have one population that we have confirmed high level of resistance to dual.
10:11
Illinois has a few popular, they have a few population they have confirmed recently we had not confirmed anything yet, but now, now we do here.
10:22
OK, So what am I trying to say?
10:25
Even our residual herbicides, we need to be really good stewards of them because otherwise we’re going to start breaking them.
10:31
And residual herbicides are incredibly important for especially for water hemp management.
10:36
OK, All right.
10:39
So Rodrigo, how do we manage this weed then with all the resistance that continues to happen?
10:45
I’m not throwing the towel yet.
10:47
I think there’s ways we can manage and I think the the most important one is the use of residual herbicides.
10:54
I had the same exact slide last year and I brought it back, you know, intentionally here.
11:02
We all know this, don’t we?
11:03
We know that we have to use pre’s, right?
11:06
But sometimes, you know, we have to make decisions on what kind of pre to use.
11:11
I’m not and I’m not here to tell you use that one versus this one.
11:16
I’m just showing you the importance of the pre.
11:20
We kind of know this, but I know when it comes down to the economics, sometimes we want to save a couple bucks here and there where we can.
11:27
And sometimes that’s the decision that will take us here versus here.
11:31
And I’m not talking about products, OK, I’m just talking about control.
11:35
So I’m trying to take a different approach when talking about priests to see if I can better convey that message because like, not that I’m failing, right, but I think we’re struggling with the idea of going to something on the far right there.
11:48
So my, the pitch here is that if you’re an agronomist or if you’re a Co-op or industry, you know you’re going to go to your grower.
11:55
And sometimes the grower doesn’t want to put the money down on the pre.
11:59
However, if you want to look good in front of that grower, if you want that grower to be really happy with you at the end of the year, especially in areas where you have heavy infestation of water hemp, you got to start with something on the right, on the far right here.
12:13
Because if you’re not on that far, right, what you’re going to do, you’re going to come, you’re going to deploy a post application, you’re not going to get full control and then you’re going to have to come back and do a respray scenario, which is going to cost you a lot more than had you invested upfront.
12:29
OK, what is my scenario here when you’re going for the very strong pre emergent herbicide about 35 days after planting and spraying, I only have a few plants and all these plants are manageable.
12:42
I can control all these plants here in this plot, whereas this situation here, this few situations, the water hemp is already past the ideal stage and there’s so much time here until canopy closure.
12:55
OK, So am I making a strong case here?
12:58
Yes or no?
12:58
All right.
13:00
And my point is not trying to sell fierce over boundary.
13:05
Boundary does very good in scenarios where you have relatively low infestation.
13:10
So if you have very or if you have well managed fields with low infestation of water hemp, boundary is going to deliver that same level of control.
13:18
But if you’re going in areas where you know you have tough water hemp and high infestation, maybe you want to stick to boundary.
13:24
But what you got to do is look at how much you’re applying, adjust rates and perhaps you can bring some additional partners here so you can deliver the same level of control that we might be seeing here in case had you used fears.
13:38
OK, So that very strategic decision early season is going to drive success at the end of the year.
13:44
So as the person making recommendation or as a person applying products, selling products, I think this is very, very important because now on my way back here, I’m going to have to call two or three different farmers that have emailed me the past couple days and say, dude, I spent 60 bucks and I’m still very, very unhappy with the level we control.
14:04
So my drive back, that’s going to be the kind of conversation that I’m going to be having.
14:08
OK.
14:08
So again, that upfront investment, it certainly pays off OK.
14:13
So that’s one point I want to make.
14:18
One day I’ll learn how to use this.
14:20
OK, as far as post emergence weed control.
14:24
I also presented this last year and I keep presenting it because almost every day in the past week here I’ve been, I’ve been asked to share this slide with people so they can use OK, so this is using straight Enlist
14:36
One post emergence. Here is just using liberty.
14:40
Here’s the combination.
14:42
OK.
14:44
And I know a lot of folks use this two way combination here this past year and they’ve been somewhat happy with it.
14:51
Folks that went just straight Enlist or just Liberty, they had to come back and do a respray.
14:57
OK, so this two way mix here Enlist plus Liberty working well in our Enlist one or in our Enlist E3 systems provided consistent we control.
15:08
OK.
15:09
I know a couple years back when I would talk about this mix, people would have to walk away because Liberty was costing us about $25.00 an acre.
15:19
But now being able to get Liberty for less than 5 bucks an acre, that’s game changer.
15:24
OK, so the Liberty or Glufosinate prices have really come down, so this becomes a lot more appealing.
15:30
As a matter of fact, farmers have learned that and a lot of folks instead of going this way, are now just going this way.
15:35
But then they’re also regretting because we all know what happens when you just spray straight Liberty.
15:40
If you have a little water hemp that has some size to it, you just don’t get full control.
15:44
OK.
15:45
So this two way mix provides higher control, but not only higher control, more consistent control.
15:51
And you’re going to hear me talking about consistency a little more often here.
15:55
So not only we want chemicals that give us high control, but we want consistency in the sense that sometimes the weeds are a little bigger, sometimes the weather is just not perfect for that particular herbicide to work.
16:06
So what are the things that work well together that provide good and consistent control?
16:12
That’s what we’re after in our program, OK.
16:16
The big question that I always get when I present this slide is Rodrigo, do I need to add dual to the tank?
16:22
Do I need to add a layered residual herbicide to the tank?
16:27
What do you guys think?
16:28
What did I say last year?
16:33
I said no?
16:34
What did you say, Jake, leave it out.
16:38
That’s what I said last year.
16:39
Don’t put that dual as part of your post.
16:42
What I would do is factor that in as part of my pre, right?
16:45
That was the message last year.
16:47
So just instead of is, I don’t want you to pocket that money.
16:50
I want you to instead of using the do as part of that post, move that up front for a stronger pre.
16:55
Just in the previous slide that I was showing you all OK, And I, I, I took a lot of heat on that, not only here, but everywhere.
17:03
Go ahead.
17:07
My I am even more firm on my attitude in drilled beans.
17:12
Then you definitely don’t need it ’cause you’re closing canopy easily two weeks ahead of 30 inch beans.
17:19
And that’s what that Dual would potentially be doing for you at that point.
17:22
So I love narrow row beans, whether it’s drilled or 15, they’ll give you at least a week to 10 days faster canopy closure than the 30 inches and then eliminates the need for that.
17:32
So yes, narrow row beans, it’s it’s a no brainer for the regular 30 inch beans.
17:39
If you’re spraying early June, yes, then I see the value.
17:44
But if you’re having to spray a post emergence application early June, I can guarantee you’re going to need another follow up post pass because there’s still a lot of canopy to happen.
17:53
But often times most of our soybean acres, they get treated towards the end of June.
17:59
Am I off here? Before beans water hemp that’s hopefully still 3 or 4 inches and not 4 inches?
18:07
Oh gosh, yes.
18:08
So, but anyway, so we decided to answer this question.
18:11
So we do a lot of small plot research and then this time, so you know what, this is the trend that Ryan was seeing with our data set and kudos to Ryan for putting all this together.
18:21
So then what I did, I went and I worked with Doug down at Lancaster Ag Station.
18:26
We had about 5 acres soybean field there that had good infestation of water hemp and by good infestation you can see here in the picture, OK, of the water hemp in the field.
18:38
And then we developed this trial here.
18:40
It’s a two treatment trial that we deployed with his commercial sprayer there.
18:44
So it’s a 30 foot sprayer.
18:47
So half of our strips we did not have dual.
18:51
The other half of the strips we added dual, OK.
18:54
So our post application was AMS, remember you need AMS.
18:58
How much dual front was applied?
19:00
I’ll, I’ll tackle that in one second.
19:02
Thank you.
19:04
That dual rate is going to be dependent on the soil texture.
19:09
Max we can go is the the 2 pints a pint and 1/2 is pretty standard.
19:13
So having that pint and a half up front, if that’s where the question is.
19:17
Yeah, perfect.
19:18
OK.
19:19
So here we did the yes, no dual, the very high rate there a pint and a half.
19:23
OK.
19:23
That’s what we did here.
19:25
And then the question is adding duo or not adding duo, is that going to improve or not water hemp control at the end of the year?
19:32
What do you guys think that I saw in this trial?
19:35
Did it improve water hemp Control or not?
19:37
And I was afraid when I did this trial.
19:40
OK, so in this in this particular trial here, do you think I saw benefit of adding Dual?
19:48
OK, so here are the results.
19:50
Right before harvest, we looked at water hemp control where I did put the dual, I had 97% + -1 standard error where we did not have the dual 96 + -1.
20:03
Statistically, they’re not different.
20:05
Is that 1% convincing you that that’s going to make a case or not?
20:10
So this is what we saw.
20:11
So Long story short, it pretty much validates what I told you guys last year with the caveat that I’m spraying here late June.
20:19
OK, So we were spraying late June soybeans or V4 V5 already.
20:24
I wish we were there a week sooner because of how windy it was this growing season and there was rain that week.
20:32
We ended up being there I think one week too late and that water hemp was already too tall unfortunately.
20:38
And I’m going to touch on that a little bit.
20:40
So if the only thing I would have changed here is I would have come at least four or five days sooner for my post application.
20:47
But Mother Nature and equipment and schedules and all that, were not working in my favor that week.
20:53
So we ended up doing a little later yet yet this was a very infested, heavily infested field.
20:59
I was surprised the level of control.
21:01
So this trial here we had a good pre emergence upfront and then we use it stink mix post emergence.
21:08
OK, why didn’t I see 100% control in this trials because of this?
21:13
That’s what we saw.
21:15
And all the time now I’m getting questions, say hey, Rodrigo, I didn’t put Dual.
21:19
I should have put Dual because now I have all these plants that harvest that I’m seeing.
21:23
They’re chest high.
21:25
You know, had I put the Dual there with my post application, I would not have seen them.
21:28
So you’re completely off because even anything that came up after that application, anything that germinates in late July or August is going to be this tall.
21:40
You’re never going to have anything that germinates that late that that tall.
21:44
The problem here is what happened here is that we just did not kill them in the first place.
21:49
You just ****** them off.
21:50
That’s what you did there because they were too big.
21:54
That’s what you did and I’m happy because I have a job, right?
21:59
So here, that’s the catch.
22:00
If you’re seeing this type of plants at the end of the year, there is not stuff that germinated and emerged later.
22:05
It’s just the stuff that we did not control in the first place.
22:09
And that’s why I bring this picture again, because some of these plants here were just too tall.
22:14
I know it’s probably hard to see it because we lost some resolution here.
22:17
This plant here has a lot of notes.
22:19
That plant is already almost 8 inches tall.
22:21
So we kind of missed the window.
22:23
So let’s just it’s not the chemistry that’s necessarily failing.
22:28
You know, it’s not other stuff that I could have added to the tank.
22:31
It’s just the whole timing.
22:32
We just missed the window on that.
22:34
OK, we good.
22:36
Yes, yeah.
22:39
Thank you.
22:39
So the the question was the carrier volume and the addition of oils.
22:45
Yeah, yeah, methylated seed oil.
22:47
So the answer to that, the both of the questions is yes, I am a huge supporter of a 15 GPA I don’t think we need to go all the way to 20 to slow things down.
22:57
So 15 GPA has done a really good job, with the caveat that we were spraying at the right window there.
23:04
OK.
23:05
So 15 GPA and 20 GPA in our trialing, they tend to do quite similar.
23:11
We don’t see a tremendous advantage like we hear across the landscape that everything should be on a 20 GPA.
23:16
I think we’re just diluting things a little bit too much.
23:18
So 15 GPA looks really good.
23:20
AMS is a must.
23:22
And remember AMS has to go in the tank first.
23:24
Treat that water good amount of AMS.
23:28
And then as far as the oils go for Enlist and Liberty, we have not seen the benefit.
23:34
I remember Jake asked the same question two years ago.
23:37
We’ve done on some additional trials, we have not seen oils improving control of Liberty and Enlist.
23:42
However, the oils or methylated seed oil, it’s our especially crop oil is essential if you have Clethidim in the tank for your volunteer corn.
23:51
So that’s the one time where I’m really going to push for the oils there.
23:54
For Liberty and Enlist using oils, we have not seen a tremendous benefit.
24:00
And sometimes when you put those oils in there and if we have some hot days like we had when we were spraying our post, you can really put your crop on fire.
24:12
Oh, hold that thought.
24:13
I’m going to have a slide on that in a little bit.
24:15
Really good question.
24:16
Yeah.
24:16
So the question was whether we tested Conventro.
24:18
We’ve been working with Conventro for the past couple years and I’m going to have a slide on that in a little bit.
24:24
Really good.
24:26
Yes, I know that sounds crazy, but potentially it’s either moving, moving the Zidro or the Dual up front.
24:36
So the beautiful thing here and I, I know putting two 15s may sound crazy.
24:41
However, the, the different group fifteens that we have out there, they require different amount of rainfall for activation and then they’re half lives is also different.
24:49
So even though they might be same site of action, they’re they’re just quite different on the way they react to different weather conditions.
24:56
If you have a lot of rain that Zidua is going to kick in, but if you have a little less reign, that Dual really tends to help.
25:02
So I, I still think there is a benefit or, or instead of having a Dual plus Zidua save and invest there either put more of one or more of the other, if I’m making sense.
25:15
So you don’t necessarily need to put the two.
25:17
You can put the two or you can adjust the rate of one of the components based on pricing.
25:23
It’s a good question.
25:25
And this idea of putting two group fifteens, we’re starting to see that if you think about storing, for instance, corn herbicide, that’s what it is.
25:33
You have Dual and Zidua.
25:36
And the the idea there is that a zidua tends to last longer.
25:40
So it can help you with late emerging water hemp, but also some grasses.
25:44
So that’s, that’s a very valid thought.
25:48
All right, so now talking about tank mixes and things that go well together.
25:52
This is research that my graduate student, Danny Zhu is leading and I just have one slide here trying to summarize his message.
26:01
And Danny started doing his work.
26:03
This work and this whole idea of tank mixes for post emergence and consistent control kind of came out of this and this slide that I just shared previously that was led by another student, Zaim.
26:13
OK, so what’s happening here?
26:15
Danny is looking at three different chemicals, right?
26:19
But Danny has a very challenging scenario for his research because he’s looking at post emergence weed control in corn, in non-GMO corn for atrazine prohibition areas.
26:30
So we’re trying to see is there something that we can use instead of atrazine that can make that Callisto work better?
26:37
Because as most of you know, if you want to see Callisto shine, you have to have atrazine with that.
26:42
But there’s a lot of areas in our state where we cannot use atrazine.
26:46
So how can we make that Callisto shine and don’t break it?
26:49
Remember, I showed the the initial slides of resistance.
26:52
We’re already breaking it.
26:53
So how can we make that Callista provide better performance?
26:55
So that’s what Danny did.
26:57
So here behind this slide, there’s a lot of data.
26:59
So he sprayed plants that were resistant or susceptible to herbicides, OK.
27:04
And they were 4 inches tall versus 8 inches tall.
27:07
And this is what we call the violin plots.
27:10
These are violin plots.
27:11
If you’ve never seen one before, what you want to look for here, You want to look for consistency.
27:16
So you want the base of the violin to be as chubby and wide as possible, as concentrated as possible.
27:23
You don’t like to see things like this because this is telling us there’s a lot of variability in your data.
27:30
OK.
27:31
So the first treatment is just atrazine.
27:34
When we have atrazine, the biomass of the plants was about 30% compared to the checks.
27:39
So in other words, in other words, third or in other words 70% reduction in biomass, but a lot of variability.
27:46
Callisto provided about 75 to 80% reduction in biomass, but by itself we had a lot of variability.
27:54
Bromoxynil, good old Buctril or now as Moxy didn’t do much by itself.
28:02
But when we start mixing things, that’s when the game changes.
28:05
So when I have atrazine plus mesotrione, as we all know, control was very good.
28:12
OK, Control was very good.
28:13
It wasn’t excellent in this particular trial, but it was very good.
28:16
What has been really surprising us is this mesotrione, Buctril or Moxy tank mix.
28:23
This two-way tank mix here is showing very consistent control and I’ve had some consultants that were in the room with me yesterday and they tried this in a commercial scale for the first time and they were very pleased with the outcomes.
28:36
So in these areas where atrazine cannot be used, OK, and they’re struggling with water hemp, this mesotrione plus bromoxynil, you did a really good job controlling water hemp post emergency.
28:49
Those of you that have used Buctril in the past, you know that sometimes crop response happens and that’s when you go fishing for about a week and then you come back and the corn will be just fine.
29:00
But for about a week, if you have just the right conditions, it’s going to look ugly.
29:05
You’re going to set the corn on fire.
29:06
And we did that in one out of six trials, OK, but there’s no yield penalty or anything, so just generating awareness, OK, There might be some crop response there, but the yield control was just phenomenal.
29:19
OK.
29:21
All right.
29:22
So now is when we start changing gears here, and I’m going to start talking about what’s coming down the pipeline.
29:28
How many of you guys have heard of Vyconic soybeans?
29:33
Kyle, what is Vyconic soybeans?
29:38
Five.
29:39
OK, 5 herbicide modes of action or five it tolerate 5 herbicides, right?
29:44
So what is Vyconic soybeans?
29:45
Viconic soybeans, I’m just using the Bayer portfolio as an example ’cause they are public about it.
29:50
I know the other companies are also working on similar trade concepts or platforms.
29:55
OK, but I’m this is information that’s coming out of Bayer’s website.
29:59
So the Vyconic beans that are going to be available to us in 2027, they confer resistance post emergence, post emergence, OK, to glyphosate, glufosinate and dicamba that’s not in use.
30:11
That’s pretty much the Extend Flex platform that we already have available.
30:17
Now they’re adding 2,4-D to the same platform and, and, and mesotrione.
30:27
I want you guys to think about that for a little bit.
30:31
This is a big deal, LG 27, but in the LG 27, LGT 27, sorry, it was pre emergence only.
30:43
This one is pre and post mesotrione.
30:46
OK, but here’s the deal.
30:48
So we have that coming.
30:50
And then you fast forward another three years in 20-30, they’re going to have what they call HT5.
30:55
So it’s all those five chemicals that I just talked about and an additional trait that confers high levels of tolerance to PPOs, Group 14s.
31:04
So imagine spraying Cobra to your soybeans and not seen any injury or imagine spraying something, let’s say Valor post emergence to your soybeans.
31:18
Isn’t that exciting?
31:20
I just hope the University will then hear that and you know, up my salary because I’m going to be a busy man.
31:26
We all right, All right, so this is what’s coming our way.
31:30
Now is when I, I stop a little bit and I ask you a question and I’m, and I’ll pose the question here.
31:37
All right, let’s say we’re in 2027 and the farmers that you work with, or if you’re a farmer yourself, you have Vyconic soybeans and now you have an option to use or not use mesotrione in your soybeans.
31:52
What what is your recommendation?
31:55
Are you going to use it?
31:57
No way yes, but I’m going to use it as part of my pre program.
32:02
Yes, but I’m going to use it post Heck, I’m going to use it always load it up.
32:10
Which way are you going to use it?
32:11
So I’ll give you like 10 seconds to think about it and then we’re going to come back to it.
32:16
All right, if you are, if your response is “A no way,” please raise your hand 123 OK, sorry folks online, we cannot do it that way.
32:26
It will get too complicated.
32:29
Pre emergence, 2. Post emergence.
32:36
Oh boy, 10 of you.
32:37
That’s kind of where we needed the most help with soybeans, isn’t it?
32:42
OK, I’m going to use a pre and post one.
32:47
There you go.
32:48
2-3.
32:48
OK, that’s good.
32:50
That’s really good.
32:52
Now the question to you is what are you thinking?
32:57
Why?
32:59
Why are you not going to use Callisto in soybean?
33:03
Yeah.
33:03
So the response was Callisto has been really good in corn.
33:07
If I use it in soybeans and I break it, what do we do in corn?
33:12
That’s that’s what I’m thinking the the whole time as well.
33:15
Somebody that said pre only, why who said that?
33:20
The convenience.
33:21
So this is where we’re heading towards.
33:23
If you’re, if you’re thinking through this simplicity here in the sense that we don’t even need to clean the tank anymore.
33:29
You can just go and that’s convenient.
33:32
But the weed scientist inside of me is just screaming right now.
33:36
Dude, what you’re doing? OK post.
33:39
Why would we use a post?
33:41
If you got a problem, you cannot handle this, use a post right?
33:45
And why use it pre and post?
33:47
Who said that pre and post?
33:49
Why would you use that pre and post?
33:52
I like where you’re going there.
33:53
We still have the other options and hopefully we’re mixing things right.
33:56
So I’m asking this because I don’t have answers.
33:59
I mean, I, I am concerned about resistance.
34:02
I think this, this thing here is going to be like the the major like swing that we saw towards enlist really rapidly.
34:09
I think it’s going to go this way with the HPPD beans.
34:13
We do not need to worry about carry over anymore from our corn applications.
34:17
We can use this.
34:18
We don’t need to clean the tank.
34:20
There’s a lot of convenience.
34:21
Convenience has led us to major problems as far as resistance goes.
34:25
However, back then we were not being strategic with our tank mixes.
34:29
We were just using the same damn thing, one single thing left and right and that took us to the wrong place.
34:36
I think we can change it.
34:38
Yes, you just, you just hit a very important word there, which is price.
34:43
And I’m going to come back to you in a little bit after I present this.
34:48
So my new student, Sabeel, he took on this project and what we’re trying to do here.
34:54
Now, we know that tank mixes tend to provide higher and more effective weed control.
34:59
That’s great to know.
35:00
But we need to know which tank mixes work well.
35:03
So poor Sabeel has been screening everything that’s under the sun here to see if we can find good ways to control water hemp.
35:10
And he’s done some phenomenal work with the assistance from Mobli, the scientists in my lab, and other colleagues.
35:17
OK, so here I have a preliminary list in front of you.
35:21
It’s very comprehensive.
35:22
It’s all like short codes.
35:23
If you’re looking close enough you can pick what the actives are.
35:27
But here I’m thinking about all our producers, I’m thinking about non-GMO growers, I’m thinking about in this growers and I’m also thinking those about those who are going to be growing Extend Flex and Vyconic in the future.
35:38
So we’re looking at all potential two way mixtures.
35:41
I think two ways is, is, is is where we got to be.
35:45
If you’re telling me we got to be spraying 3 or 4 different things post emergence, we have a huge problem.
35:49
I don’t want to go there.
35:51
I think two ways is, is the way to go and that’s why we’re doing it.
35:54
So he’s just done this for soybeans and he’s going to start this for corn.
35:58
We did everything in the greenhouse so we could sort out preliminary treatments that are showing very high levels of control, but also being consistent so we can take them to the field and then try to adjust adjuvant packages and so on.
36:12
So that’s the first piece.
36:14
Here’s where we go next.
36:16
OK, so I just want to share with you some of the very promising tank mixes.
36:20
Some of the tank mixes you’re not seeing there, they’re above the 90% would be our glufosinate and 2,4-D that I talked about already.
36:29
And then the other one that’s also promising that I’ve been recommending based on Nicholas work to our Extend Flex farmers is Liberty Glufosinate plus Flex Start.
36:39
So this 2 tank mixes, they’re above the 90% mark, but they did not make this final cut that I have here on the 95%.
36:47
The ones that the ones that made the 95% cut are going to be our 2,4-D plus fomesafen, OK, 2,4-D plus mesotrione looked really good.
37:01
Glufosinate plus Lactofen, believe it or not, glyphosate and 2,4-D still still did quite well in this trial, OK.
37:10
And I just want to give you a little more background information on this trial.
37:13
For this particular experiment, what Sabeel did, we have three different populations of water hemp.
37:19
We selected three nasty water hemp populations from Wisconsin to do this.
37:23
So it’s not just one population, it’s multiple populations behind this.
37:28
The best 2 treatments there, 2,4-D and Lactofen.
37:31
But the one that blew my mind was that one right there.
37:35
Can you guys tell me what you think that is the best one?
37:38
The highest control with the least amount of error.
37:42
What is that?
37:44
If you were to guess what glu plus? So mesotrione and liberty, what is the cost of this?
37:56
We’re talking $7-7.50 here.
38:00
Where can we use this right now?
38:03
Where can we use this tank mix right now?
38:07
Where can we use this tank mix right now?
38:09
Which crop?
38:11
Because here I’m thinking like, you know, the Vyconic beans, right?
38:16
But this thing kind of came as a slap on the face.
38:18
And I start talking with some people out there and some people have figured this out.
38:23
And this is where the weed scientist inside me is screaming again, right, ’cause we need to protect liberty for our soybeans.
38:31
However, we’re having issues controlling water, hemp post emergence in our corn in the sense that dicamba is really struggling.
38:38
So everybody’s like, we need something else in corn.
38:40
Where are they going towards? Liberty.
38:43
And most people are just using straight Liberty.
38:45
And I think that’s a mistake.
38:47
A few people, especially the Central Sands, they’re doing Liberty plus an HPPD herbicide and from them.
38:53
And then I start talking with our industry colleagues.
38:56
This two-way mixture is very, very effective.
38:59
And it just so happened to be incredibly affordable.
39:05
But then, you know, how can we be good?
39:07
I, I have to share this with you guys.
39:09
It’s my responsibility and it’s tough spot to be because I don’t want to.
39:14
I just told you guys, we found resistance to HPPD, but guess what, one of the populations that is HPPD resistant is behind this data set.
39:24
So the tank mixes even you might be having that resistance building there.
39:28
Dead weeds don’t set seeds.
39:31
When we have dead weeds, we slow down the whole resistance train wreck.
39:36
Are you guys with me here?
39:39
OK, so we’re talking $7.50 post emergence, that’s going to do great.
39:45
All right, how long is this going to work for?
39:47
I don’t know.
39:48
OK, but that’s one of the tank mix.
39:50
There’s possible there’s like 3 or 4 tank mixes here that look really good.
39:54
So if we’re if we want to take this resistance problem seriously, if we’re taking this seriously, OK And we still want the convenience that was described going to put a good pre down and we’re going to be using effective mixtures post.
40:09
And we’re going to be spraying them at the right time because if we don’t do, I’m back with my job security joke all the time.
40:16
That’s getting old.
40:17
But you guys still laugh.
40:17
So I still use it.
40:19
OK, But that’s the catch.
40:21
But there’s this two way mix here, the consistency.
40:24
We’re going to take it to the field.
40:25
And I feel confident coming here and talking to you because we’ve seen this in the field already.
40:30
I talked to Ryan and Ryan said, yeah, we’ve seen this in the field.
40:32
It looks good.
40:33
And I’ve talked to some colleagues.
40:34
It looks good.
40:35
If you try this in corn, what is the one thing you must be sure of before you go and you have the freaking right trait in the field?
40:47
Because if not, guess what?
40:48
It works really well on non liberty link corn too.
40:53
So that’s the convenience aspect.
40:55
Then if you were just running the rig, if you got non Liberty link corn and you put Liberty on top of that, you will never forget that day.
41:04
OK, All right.
41:06
So somebody asked about Convintro.
41:08
So this is a good time for that.
41:10
These are the new products that we tested in our program this year.
41:13
They’re all presented here in alphabetical order.
41:17
This is a summary by Ryan, the research specialist in our lab.
41:21
So this is the stuff that we were testing.
41:22
Some of this is already commercially available to you all.
41:26
Some are still pending EPA registration.
41:28
And with the whole shutdown, things have slowed down a little bit.
41:31
But the first one there is Convintro in my list.
41:35
What is Convintro?
41:36
Convintro is a is diflufenican.
41:39
Diflufenican is a new mode of action that will come our way for corn and soybeans.
41:46
It’s not new chemistry.
41:47
It has been around for a while, but we have not used it in corn and soybeans here in the Midwest.
41:53
So it’s going to be new to us.
41:55
That part is exciting.
41:56
It’s a new mode of action.
41:59
The strength of diflufenican is Amaranthus species.
42:03
They’re pigweeds.
42:05
That’s why there’s a lot of excitement.
42:06
So diflufenican, the the target species of diflufenican is Amaranthus OK or our water hemp out there.
42:15
So it’s very specific.
42:16
So if you’re relying on the diflufenican, it doesn’t do much on the other weed species.
42:20
Is, is OK on water hemp.
42:23
It’s not something you’re going to spray alone and it’s going to do wonders.
42:25
It’s it’s part of a integrated mix.
42:28
OK.
42:29
So diflufenican is the first one.
42:31
The next one is Kyber Pro.
42:33
You guys have heard of Kyber before.
42:35
They had some formulation changes there, so now it’s Kyber Pro.
42:39
As far as active ingredients go, is the same thing as in Fierce MTZ.
42:43
So you have Zidua, Valor, plus metribuzin in there.
42:46
That’s the three-way combo.
42:47
It just got reformulated.
42:50
We did some testing and is now registered and available to you.
42:54
We’re not going to be seeing Liberty 280 anymore.
42:57
Now it’s all Liberty Ultra.
42:59
Liberty Ultra has a higher concentration of the L isomer, which is the active isomer, OK, that does the the weed control for you.
43:08
So now it requires a lower use rate.
43:11
So historically we use 32 fluid ounces of Liberty.
43:15
If you’re using Liberty Ultra now you’re going to be using 24 fluid ounces, OK.
43:19
So it’s a lower use rate of that product, one that’s kind of new to us and we talked a lot about it during our few days this year.
43:29
If you came for a few days, you actually had a chance to see it as Rapidicil.
43:33
So that’s a new PPO herbicide by Valent.
43:37
It’s a Group 14 herbicide that provides a quick burn and I’m going to show that in a little bit.
43:43
What’s unique about this is that it doesn’t have residual control, but it has grass activity.
43:51
And remember when I was talking about the HT5 trait?
43:54
So right now if you spray Rapidicil on top of beans or corn, you fry them.
43:59
But when that HT5 trait becomes online in 20-30 or afterwards, then you can spray Rapidicil on top of soybeans and eventually corn.
44:11
So you have that PPO chemistry as an option post emergence, but for now it’s burned down only.
44:16
OK, so Rapidicil is the name of the chemistry and I’m going to bring, I’m going to come back to that in a little bit.
44:21
Corteva just released Sonic Boom.
44:24
So it’s a different version of Sonic.
44:26
It has sulfentrazone and metribuzin.
44:29
And then lastly, BSF is going to come up with Zidua Plus.
44:33
Zidua plus is Zidua plus imazethapyr.
44:36
The only difference between Zidua Plus and Zidua Pro is that Zidua Plus does not have the sharp end.
44:43
So the Zidua Plus right now has the flexibility of spraying pre emergence or early post emergence.
44:50
OK, so this is what’s new in the pipe that we are testing that will soon be coming your way.
44:56
Now I want to talk about Rapidicil here for a little bit.
44:59
We have the data here that Ryan put together.
45:02
So we did different pre herbicides with and without Rapidicil.
45:07
I think the pictures helped me better convey the message.
45:10
So this is a no till scenario.
45:11
So we planted corn into soybean stubble and we had giant ragweed that come early in this field.
45:19
OK, so this is down at the Rock County farm.
45:21
I planted corn, didn’t do nothing.
45:24
Five days after, here’s my giant ragweed infestation.
45:28
It’s important to mention that by the time we were planting corn, the giant ragweed, some of that was already established.
45:33
OK, so here is just giant ragweed. Our non treated check.
45:36
Here’s where we just burned that down with glyphosate.
45:41
And the problem with this population is that is is developing tolerance or is becoming resistant to glyphosate.
45:47
OK, And you’ll see that in a couple more pictures.
45:50
Here’s Storen, which is a really good pre emergent herbicide, but Storen was mixed.
45:54
with Roundup, you’re still seeing the giant ragweed.
45:56
Here is Maverick, which is supposed to be doing a similar job as Storen is doing here from a residual standpoint.
46:02
But the difference that we added Rapidicil and what’s fascinating about Rapidicil is you spray it within three to four days, the sensitive weeds are gone.
46:11
So it’s a very fast acting herbicide.
46:14
What is the other herbicide that does that for us?
46:17
That’s a very fast acting herbicide Paraquat.
46:24
OK, So this is not by any means like a paraquat replacement, but it kind of fits those scenarios where you need a quick burn.
46:32
OK, So there’s a lot of folks that we have maybe would be an option, but we cannot spray or we don’t we don’t want to spray or we can’t get somebody to spray it.
46:40
This is the potential.
46:42
But this is where I think I get OK.
46:43
So just keep going with the photos.
46:44
So that was 5.
46:45
This is 13 days after application, OK, And you can see that the plots are very clean here.
46:51
The giant ragweed and the Storen plots are starting to die because now you have a combination of the HPPD also kicking in.
46:57
OK.
46:58
And look what’s happening, the untreated check round up and then 20 days after, because that giant ragweed is building resistance.
47:04
This is just regrowing back.
47:06
Whereas here now we finally have clean plots both ways.
47:09
So again, for the rapid desiccation, the Rapidicil has potential.
47:13
It’s a new chemistry.
47:14
I want to make you guys aware of that.
47:17
But as far as conservation agriculture goes, our colleagues here talked a lot about cover crops conservation systems this morning and also this afternoon.
47:25
This is where I think this is exciting.
47:28
What we’re looking at is using Rapidicil as part of our cereal rye cover crop termination.
47:34
So I’m going to jump straight to the photos.
47:36
So here’s corn that we planted green.
47:39
So we had about a foot tall rye and we wanted to plant green into that rye.
47:46
This picture was taking seven days after planting and spraying.
47:49
So here is just Roundup.
47:51
Remember in May, it’s cold.
47:53
It takes a while for that rye to die, right?
47:56
The next treatment here is Roundup plus atrazine.
48:00
And I think I’ve talked about this in the past, when you mix Roundup with a clay based herbicide, you have a little bit of an antagonism there in a very slow death of that rye.
48:09
So seven days after we only had 30% control, that rye was pretty green.
48:14
Still remember I already planted green.
48:17
My corn is starting to come up.
48:19
Here’s the Rapidicil plus Roundup.
48:22
Within a week that rye was dry.
48:24
So we enabled us to plant green and get a fast, quick kill of that rye within a week.
48:30
So in this conservation systems where we are planting our corn green, if you want to see a quick death of that rye, that’s a potential and OK.
48:39
And then here’s even when we mix the Rapidicil, Power Max and Atrazine, it kind of overcame that antagonism that we were seeing.
48:48
What is the plant back on the Rapidicil is an excellent question.
48:51
I’m glad you asked.
48:52
So for corn, you have to spray before planting or a day before planting.
48:57
And soybeans you can spray up to three days after planting as of today.
49:02
And it’s the same thing for winter wheat, you can spray Rapidicil one day up to one day before planting.
49:08
So there’s a one day margin there for corn, not that we know as of now.
49:17
OK, so here’s a picture taken 14 days, 16 days after.
49:22
See that antagonism situation that I was talking about, Corn is still green, whereas here is dry.
49:28
And then a 21 or 28 days when this picture was taken, finally this this rye here is dead.
49:33
So it just took a while for this this treatment here to get fully controlled, whereas we had a fast cue.
49:40
Yes, yeah.
49:41
So the question was did did we need a roundup in there?
49:45
And that’s one of those that I wish we had that treatment, but we didn’t.
49:50
But my answer to you, I do think we need the, the roundup in there.
49:53
Just the Rapidicil by itself, you would not have done this.
49:57
So the, the roundup I, I am confident would still be needed.
50:01
We’re going to be doing this trial again next year.
50:03
And I’ll, I’ll bring you the confirmation.
50:05
But again, the question was, could you just have achieved this level of control of the rye with straight Rapidicil?
50:10
I don’t think so.
50:11
I, I still think we need a roundup in there.
50:13
I’m actually, I’m actually pretty confident on that.
50:16
So good question.
50:17
Yes, yeah.
50:19
So the question is when was that sprayed?
50:21
We sprayed that early May.
50:23
Yeah.
50:24
So early May is when we sprayed.
50:25
So we planted the corn early May and then we sprayed early May.
50:28
All right, folks.
50:29
So here’s the deal.
50:29
It’s already past my time.
50:31
So it’s it’s 3:05 and I have another three hours of content here.
50:37
I’m just kidding.
50:38
I have another 10 minutes, but I want to be respectful of your time.
50:42
Do you guys want me to go 10 more minutes or you want me to stop? And you will not hurt my feelings.
50:46
I got 10 more minutes.
50:49
Can I have 10 more minutes online audience?
50:53
You’re giving me 10 more minutes.
50:54
All right, The folks here in the room, who’s the clock is OK to go.
51:00
All right, so I’ve talked a little bit about this work.
51:03
This is the PhD research by Guilherme Chudzik and he, he wrapped up this project.
51:08
So I just want to bring some updates.
51:10
All right?
51:10
You all know that we’ve been doing work with planting green.
51:13
Steven, that was the question that I was posing to you.
51:16
If we start delaying the termination, can we help with some of the phosphorus?
51:19
Because that early planting of the rye sometimes is not realistic, but can we delay on the back end and benefit the same way?
51:26
So this is where I really want to pick your brain.
51:28
Go ahead, Steven.
51:30
Yeah, yeah.
51:30
So the key point with those scenarios, we were trying to keep the yields the same, right?
51:34
Not have to argue with people about, oh, you know, how much yield drag or not to put in there.
51:39
So try to keep it real simple.
51:40
But now things are set up.
51:41
I agree.
51:42
I think we can start playing on the back end and maybe doing doing different flavors.
51:46
So very, very exciting.
51:47
Thank you! For corn?
51:49
All right, so when we’re talking planting green and this biomass madness, I’m talking about soybeans.
51:53
OK, Let’s not go there with corn.
51:55
Corn doesn’t like this.
51:56
So this is soybeans.
51:57
All right, OK, so this is where we were going.
52:01
We need about 4500 lbs of dry matter.
52:04
This plot here, we had about 6000 lbs of dry matter.
52:07
The the rye was heading out.
52:08
So I love this for weed control, OK.
52:11
And often times we don’t get a yield hit unless your planter is not properly set up and then you end up with problems in the stand and it’s a disaster.
52:19
OK, so there’s a lot of concerns, but the other thing is that Shawn Conley is not here.
52:23
So I’m just going to throw him under the bus, right?
52:26
No grower wants to wait until mid-May to plant anymore.
52:29
They might as well be planting now.
52:34
Already missing GDDS out there, right?
52:36
Plant early, plant early.
52:38
The seed in the bag doesn’t yield, right, whatever that means.
52:40
So but anyway, so we have this conservation systems, we know the right biomass can help, but we got to be realistic.
52:47
No one wants to wait until this.
52:49
And I’ll be honest, like planting into this is a pain in the **** OK?
52:52
So why not try to get the yield potential by planting early and try to benefit from the biomass that cover crop?
53:00
OK, Well, then what you got to do in the system?
53:02
Don’t kill that rye so early.
53:04
Let that rye coexist with your soybean crop.
53:07
And people think I’m mad, right?
53:09
Say you went mad.
53:10
I mean, we’re never going to do that.
53:11
And that’s why we do this in the research trials.
53:13
And my answer to you is it’s possible.
53:15
And some folks are doing it so you can still go and plant early.
53:20
We did this trial at 20 different locations in the United States, OK, in the upper Midwest.
53:26
And you can do it.
53:27
You can plant early.
53:30
You can plant early.
53:31
So this trials were planted in Wisconsin April 20th, the earliest we could go after insurance kicked in, so April 20th.
53:38
And then we allowed that cover crop to grow for about 15 more days.
53:42
And by giving it 15 more days, it doubled the amount of biomass and it helped us without impacting the soybean.
53:50
So now I’m going to show you some data to convince you of that.
53:53
So here’s when we plant green.
53:55
This is the amount of biomass.
53:56
Rodrigo’s not happy yet because we don’t have enough biomass, people! Delay the termination.
54:01
So when we planted green and terminated, when we waited for the beans to be at the germination stage, VE stage.
54:08
VC right here.
54:09
We’re getting to where I like to be.
54:11
OK?
54:11
This is what our research has shown.
54:14
Multiple papers here.
54:15
Lots of lots of research to just put one line.
54:18
It’s amazing how much work goes behind one line here people, you have no idea.
54:22
Years of our lives dedicated to this one line.
54:24
But here this this is the sweet spot.
54:27
OK, So if you have your soybeans that about VE we’re getting to that point.
54:32
Rodrigo’s happy your water hemp is unhappy.
54:34
We’re good.
54:35
OK.
54:36
The question then you asked me is Rodrigo, we don’t weigh biomass, right?
54:40
We’re practitioners.
54:41
Tell us a proxy. Guilherme did that for you.
54:44
And what Guilherme is showing is look, you don’t need to clip biomass and weigh it’s about 30 inch tall rye.
54:51
So about 30 inch tall rye.
54:53
You got to where we want to be.
54:55
Let’s look at yields.
54:57
So here’s our soybean yield when we planted green and here’s a lot of data behind this, OK, When we plant green and terminate the day off, when we terminate the rye at the germination stage and here’s at the VE stage.
55:10
So no differences from terminating early.
55:13
We maintained yield and we’re talking about 15 days difference here.
55:17
So we’re giving the rye 15 more days to grow without impact or yield.
55:22
The caveat is you let it grow, another growth stage, you lose about 5 bushels.
55:27
Another growth stage, about 10 bushels, another two more growth stages, 30 bushels.
55:33
So that’s the catch.
55:34
You can let it, but you got to do it like clockwork.
55:38
About 15 days in, you got to go and kill it because if you let it extend, if the weather turns on you, then it gets risky or the Co-op doesn’t show up, then it’s problematic.
55:48
OK.
55:48
So that’s the one caveat of the system.
55:51
So this is what we’re talking about.
55:52
This is the stage here that if you’re terminating that rye up to the stage, according to Guilherme’s data here, no yield impact impact.
56:02
Now if you get to this stage, then you’re already losing yield.
56:06
So it’s like a one stage difference, you start losing yield.
56:09
Yes, Sir.
56:09
Yeah, so that’s a really good question.
56:11
I showed you guys the slow control.
56:13
That concern is primarily for corn.
56:16
In this case here, we saw the same thing.
56:17
So we sprayed at this VE stage and then there was a slow death of the rice.
56:23
We’re accounting for that when I’m presenting this to you.
56:26
So if you’re actually spraying up to this VE, you’re good.
56:29
If you want to be a little more conservative, which I encourage you to be, especially early on, perhaps do it here.
56:35
OK, So then by the time it’s here, it’s already dead.
56:38
But when we’re presenting this data to you, we do account for the slower death with the glyphosate.
56:43
It’s a really good question.
56:45
OK.
56:46
So when you get to this stage, Guilherme shows we’re losing about 5 bushels to the acre.
56:51
So this becomes a little, a little late, OK.
56:54
So this is our recommendation coming down to 1 slide, OK.
56:58
So my recommendation from years and years of data is 30 inch rye looks really good.
57:04
And if you planted that green and early, you either terminate at this stage or if the beans are emerged, because if the beans are already at the VE stage fully emerged, OK, and your rye is not there yet, I recommend you to terminate ’cause otherwise you’re gonna start stressing up too much or beans.
57:22
Once the beans start passing at this stage and you still have that green, round, green rye around it start competing for light, gets really spindly, you start losing stand and that impacts your yield.
57:34
So this is kind of that sweet spot, either or.
57:37
OK?
57:37
So you can plant early and you can still benefit from the cover crop, hopefully from a phosphorus loss system, but definitely from a water ham standpoint.
57:47
OK, Rodrigo convinced me.
57:48
Oh, Guilherme always has this caution here.
57:50
If it’s too dry, don’t do this thing.
57:51
It’s madness, right?
57:52
If you’re looking at the forecast, there’s not a drop of water.
57:54
Always go early.
57:56
Don’t don’t go on the late side because it can be problematic.
58:00
But here’s the weed data at the time of post application.
58:04
At the time that we went out there with Liberty and Enlist, if I planted green and no herbicides, I had this amount of plant in a square meter, OK, that I had to control post emergence.
58:15
Here is what happens with the amount of weeds in season as I let my cover crop grow.
58:21
The more biomass, the more suppression.
58:24
We talked about this right here’s when I integrate that with the residual herbicide.
58:29
So just by using a herbicide at the time of planting, this is the amount of plants I’m going to deal with post emergency.
58:35
Allowing more biomass with a herbicide looks a lot better.
58:39
This is true integrative management here in front of you and this is what Guilherme did here.
58:43
So you’re going to plant early, you terminate at that point, you’re going to have a lot of weeds to control in season.
58:49
You bring you delay your termination without a residual herbicide, you have a 33% less weeds to control.
58:56
You do a herbicide with a cover crop, you have about 50% reduction on the weed density in season.
59:02
You have a higher amount of biomass which is what I’m recommending to you today.
59:06
Combined with a pre emergence herbicide you have a 70% reduction that weed density.
59:12
So the strategy is really working together here to lower the weed pressure in season.
59:17
Yes, Sir, that is a beautiful question.
59:20
I love that question because that was the that is the next version of the project and Guilherme.
59:24
I get too excited with data and I want to run with everything.
59:27
The guys say calm down.
59:28
We we got to look at more time, but initially this is where I was going.
59:32
So you got to plant and spray your pre.
59:36
Then you wait until VE come with glyphosate to kill the rye and then you have to come back again to do a true post application.
59:44
How many people want to do that?
59:47
Not many.
59:48
And I know that we’re somewhat limited to two passes, right.
59:52
So we’re, we’re researching that at all this site years here across the US, what we’re learning is and it blew my mind because I thought we needed a pre here and then just you know exactly where you’re going.
1:00:04
But what our data says is that delivering a pre here at this stage provided better or not that that is no longer a pre because the crop is already up.
1:00:16
Delivering your early season residual program here did better than here.
1:00:21
In a 2 pass system.
1:00:23
So killing the rye and delivering A residual herbicide at the same time followed by a post application was better than that three pass idea that you just asked, which blew my mind.
1:00:34
But that’s the consistency of the data’s there.
1:00:37
The caveat here is that once your crop is emerged, you lose metribuzin, you lose Sharpen, you lose Sulfentrazone, and you’re losing Flumioxazin.
1:00:46
So you’re losing some important chemistry that might change in the future with the traits, remember, but not as of now.
1:00:53
So you’re down to Warrant Ultra.
1:00:56
So I’d love to see Flexstar then as part of your mix.
1:00:58
Flexstar has residual. Warrant Ultra prefix, right?
1:01:05
Or you can start making your mixes there with Flexstar Plus Outlook, Flexstar plus Warrant, Flexstar plus Zidua, Flexstar Plus Dual.
1:01:13
And I would definitely bring Pursuit into the mix.
1:01:17
It’s affordable and it’s really good in small seeded grasses and some of the other small seeded brow leaves other than water ham.
1:01:24
So the three-way combo of 15, Flexstar, and then a group 2.
1:01:28
Usually pursuit tends to do really well here in the system.
1:01:31
So you put your residual and you kill the rye here and then you come back with your post.
1:01:36
So it’s still a 2 pass system and it’s showing.
1:01:39
It’s, it’s looking pretty good.
1:01:40
The, the, the madness there.
1:01:42
I know where you’re going because of the interception, right?
1:01:45
So the big question that we have too is how much interception are we having?
1:01:48
We do get interception.
1:01:50
And right now we’re doing a series of projects for the past few years where we’re looking at all the potential chemistries that we can use, you know, from a residual standpoint.
1:01:59
And if you want to find out which ones are more compatible, so give us about another month, month and 1/2.
1:02:05
So we send a lot of samples to Mississippi State Chem Lab and $30,000 to a lot of money.
1:02:12
And the data is supposed to be coming back.
1:02:13
There was a delay on the payment the the universities don’t want to release the data yet, but it’s coming.
1:02:17
Give me another two months here and we’ll have some answers for you.
1:02:20
Which chemistry is more compatible with these conservation systems in the sense that they will travel through the residue and get to the soil for residual control of water hemp?
1:02:29
It’s a really good question.
1:02:31
Did I answer that?
1:02:32
I spoke for like 30 minutes.
1:02:33
I don’t know if I answered it.
1:02:34
OK, thank you.
1:02:36
So Guilherme says here, resistance herbicide, resistance management is a numbers game.
1:02:40
Bringing all the strategies together, planting green delayed termination with residual herbicide is looking very, very promising.
1:02:47
OK.
1:02:48
So with that said, I just want to thank you guys.
1:02:51
Sorry for taking a little bit of extra time here.
1:02:53
There’s a question.
1:02:53
OK, Yeah.
1:02:55
So the question is, are we going to have Vyconic soybeans in our plots?
1:02:57
So we’re already working with Bayer, but we were doing primarily bare ground trials cause working with genetics that’s not released yet.
1:03:05
It’s complicated.
1:03:06
That’s all I’m going to say.
1:03:08
But next year we do hope to have the genetics in our plots.
1:03:11
Then you guys can come see it at the field days.
1:03:13
That is the hope for that.
1:03:15
Yeah.
1:03:16
But we’re already doing trialings with Bayer, looking at platforms.
1:03:19
Yeah, yes, yeah.
1:03:21
So the question is the whole tie up here.
1:03:23
So that’s why I also like this 30 inch tall rye ’cause if you’ve been to a 30 inch tall rye, you still see soil.
1:03:31
So you’re not fully intercepting.
1:03:33
Once you already passed your mid thigh, that rye canopy is fully closed.
1:03:37
There’s a lot of interception there.
1:03:39
But when you’re still that 30 inch, you’re still seeing soil.
1:03:42
So there is some interception, not a whole lot.
1:03:44
And if you’re lucky, it rains in the next day, then you’re gold.
1:03:47
And that’s why we’re looking to this this data set here ’cause it’s gonna tell us which molecules are less likely to be absorbed with a D to the green leaf of the rye that is more prone to be washed off by eventual rain.
1:04:03
But we also looking for molecules that are photostable because sometimes when we spray to the rye and it doesn’t rain for 2-3 weeks and that happens in OTO in conventional TO2, right?
1:04:14
That’s those molecules might be exposed to sunlight for too long and start breaking down.
1:04:18
That’s what we’re looking into.
1:04:19
We’re thinking about you guys.
1:04:21
We want to make sure that what you’re spraying is compatible to that system.
1:04:24
And we’re also looking at things that tend to hold together better when you have different years.
1:04:29
Some years are very dry, some years are very wet.
1:04:31
So remember that consistency that was talking about the whole time for post controls?
1:04:35
We’re trying to do that too with our pre herbicides.
1:04:38
Alright everybody, thank you guys so much.
1:04:41
Sorry for the extra time.
1:04:42
Yes, Scott.