In this webinar, Josh Kamps, UW–Madison Extension regional crops educator, covers how to assess plant populations, determine crop growth stages for corn, soybeans, and wheat, and properly collect and interpret soil and tissue samples.
In this video, Josh Kamps, Regional Crops and Soils Educator with UW–Madison Extension, provides an in-depth training session on crop staging, stand counts, and soil and tissue sampling.
Josh explains the importance of these practices for making informed decisions about replanting, nutrient management, and crop protection. The session also includes practical tools like the Bean Cam app and sampling techniques for both conventional and no-till systems.
Resources
Be prepared
- Web Soil Survey or download the Soil Web phone app (Apple, Android)
- Tool Checklist & Reporting Template
Pest & crop management calendars
General crop scouting resources
- Crop Scouting Basics for Corn & Soybean – Crop Protection Network
- Crop Scouting Educational Resources – Iowa State University
- Growing Guides – UW Madison Integrated Pest & Crop Management
- UW Plant Disease Diagnostic Clinic
- UW Soil & Forage Lab – Soil Sampling
- UW Madison Department of Entomology – Insect Diagnostic Lab
- UW Plant Disease Diagnostics Clinic
Transcript
0:05
All right, so I have, I have 12:00.
0:07
So I, I do think I’m going to get started again.
0:09
Just a brief introduction.
0:10
Josh Kamps, regional crops and soils educator with extension.
0:15
I cover Jefferson Rock and Walworth counties.
0:19
I’ve been with extension since 2018.
0:22
I started in the southwest part of the state, Grant Green, Iowa, Lafayette counties and then moved with my wife and our our our dog to Janesville, so closer to my wife’s family here in Rock County and serving this area.
0:39
Now today we’re going to talk about crop staging, stand counts and soil and tissue sampling.
0:46
So hopefully we can keep some interest on in this talk, in this discussion, I’ll build this out a little bit more and we’ll have some love, a chance during our three in person trainings later this summer.
1:00
If you are able to attend those, you know where we can really go to the field and practice some of these skills there.
1:08
OK, so I see a few more names are coming in as I was introducing myself.
1:12
So again, Josh Kamps with Extension, we’ll get started here.
1:17
All right, so while you’re finishing up with that outline or excuse me with that demographic survey, just a little bit about what we’re going to talk about today.
1:26
I’m going to actually start with some stand counts, give you some basic information on, you know, taking that stand count as our crops are, you know, starting to emerge or even, you know, getting into some of those different growth stages.
1:40
That is the next topic then is doing some crop staging for corn, soybean, and then I included wheat as well.
1:49
You know, what stage of growth is that crop in?
1:51
There’s some important reasons why we want to learn that skill.
1:57
It’s one that we’ll use then just kind of without a lot of thought as we’re entering fields, you know, in the future, we’ll be able to kind of do a quick assessment, you know, what, what stage that crop is at to help with some decision making for the for the operator.
2:14
And then we’re going to end with a conversation about soil sampling and tissue sampling and why we might, you know what, excuse me, how, how we kind of do those processes in the field and then some different timings that we might utilize that.
2:30
So to begin with, stand counts, it’s as simple as as it sounds, we actually are, you know, counting, getting an idea on that stand, that crop stand in the field.
2:41
So how many plants are are in a certain field, the density of those plants across that acre of land.
2:51
It might, you know, help with us assessing that crop’s yield potential.
2:55
There’s obviously a lot of factors, you know, with the crop that is just emerged that’s going to impact the yield potential of that crop.
3:04
But the amount of plants, you know, in a given area of the field.
3:08
So the amount of plants per acre is one of those main factors.
3:13
OK.
3:13
Those are the reproductive sources in the field.
3:18
Those are the little factories in the field.
3:19
So, you know, we, we have a goal and we set the corn planter or the soybean planter up and how close do we meet that goal is really what some of this initial work is.
3:30
So this might be, you know, a, a project that that you as a, a crop scout would undertake when you, you know, are going to some of these fields early on is getting an idea of that stand dent density, you know, how many plants are in a field per acre.
3:47
It might also aid with making some replant decisions.
3:51
So if a cropped stand is not adequate, if we don’t think we’re going to be able to reach a yield potential goal that the grower has, you know, it might become a time when they want to plant a different crop or replant the same crop to try to get, you know, a higher yield, put potential in that in that crop.
4:14
And then there are there are some tools that we might use.
4:18
I have them broken out here by these three titles.
4:20
A traditional method, a hoop method or a camera method.
4:26
OK, so you’ll, you’ll need to have some basic information when you’re going to the field to take these stand counts.
4:33
And really it’s going to go back to how we’re measuring 1/1000th of an acre.
4:39
OK, so it depends on the row width.
4:43
You can see I have a table there that’s out of one of our replanting guides that Dr Joe Lauer had put put together.
4:51
But this is that basic information.
4:53
So if we know the row width of the crop, we measure that length and that gives us 1/1000of an acre, OK, So kind of that standard corn planting width is 30 inches.
5:08
So that would mean we have to measure roll length of 17 feet, 5 inches, count all the plants in that area and then take that times 1000.
5:19
That’ll be our planting density for that spot in the field.
5:27
Here’s another example.
5:28
This is more in line with what our soybean planting width is.
5:32
OK, so again, you can see 30 inches there, 17 feet, 5 inches, but then it goes down from there.
5:40
You know, another popular width would be 15 inches.
5:43
So that’s twice, twice the row length.
5:46
All right, to get to that same 1/1000th of an acre.
5:51
So as we narrow our rows, we often, you know, have a little bit greater spacing between the seeds.
5:58
So that’s why we need to measure a little bit longer area to get a better reflection of what that entire area in the field in the field is.
6:10
OK, a different way to think think about it is to use some type of measured area.
6:18
So like a hula hoop for instance, is what this type of type of tool is some some type of circular, you know, object that is pretty uniform so that we can have a diameter across and and then we have a factor.
6:35
So for instance, if you have a a hula hoop or some type of a ring with a diameter of 21 inches, that factor then is 18,119.
6:47
So what that means is we’re going to count all those plants within that ring.
6:51
All right?
6:52
And then we’re going to come back to this chart and multiply it by that factor.
6:57
All right.
6:58
So it’s a different way to do that density, that plant density across the field.
7:06
It it may work, you know, for the crops that you’re looking at it may, it may work better to just do that row count.
7:13
But another tool that I wanted to share, and this, this chart is available actually in, in the Purdue publication.
7:22
But you know, if, if you want to take a screenshot, you know, this is all public information that that once you kind of have this chart, you know, then it then it works for when you’re out in the field.
7:37
Another method that that may be of interest is this camera method.
7:45
The cool Bean lab at UW Madison has, you know, worked with some of the computer technology people on campus and has come up with what is called the Bean Cam.
7:59
OK, so it’s a, it’s a app.
8:01
I have a screenshot there of what it looks like.
8:04
I had our integrated pest and crop management site so you can download that, you know, with iPhone or iPad or if you have an Android tool.
8:18
The link there is is there as well.
8:20
And I see it just got added to the chat.
8:23
But the way this is set up is we take 5 pictures.
8:28
I have a little example for you there on the right hand side of the screen field.
8:33
I put a name up there.
8:34
Johnson 2 is the name of the field and I have those five different sample pictures that were taken and it gives me an average.
8:43
There’s some calibration instructions there for how you might want to set that.
8:49
What I ended up with for estimated population was just under 100,000 plants put in the date.
8:57
You know that I was in the field taking that this, this was last year.
9:00
I actually was looking at a field that has some slug damage to the soybean plants.
9:07
It gives you a recommended, you know, fill in rate of how many seeds you might want to add.
9:13
But then what’s interesting is the the research that Shawn Conley’s lab and others across the country have done is, you know, what is the potential of reaching our maximum yield with the current stand we have and then also, you know, with adding additional seeds to the field.
9:32
All right, so you can see both of those stands are at 100% of yield goal.
9:38
So it really wouldn’t make sense to add any additional, you know, bean seeds to that to that field since we were able to meet that goal with the stand that we had.
9:48
All right, So a little bit extra information there maybe than what you know you’ll, you’ll be collecting, but it’s another tool that it might, it might work out, you know, if you have a smartphone with you, it might be a kind of a quick way to do that across the field.
10:06
Maybe compare that to one of those other methods and you know, kind of see how is it working for you and the conditions that you that you have.
10:18
OK.
10:18
And a little bit about small grains.
10:20
A lot of those decisions have already been made, but I, I thought it was important to include it.
10:26
It’s something that I think we do every spring, you know, if we plant a small grain crop, is it did it over winter?
10:34
Is it a a good enough stand?
10:36
Some sometimes we do that from the windows, from the the windshield, right.
10:42
But there’s reasons to get out in the field and with your with your work.
10:46
You know, that’s, that’s one of your main goals is to give that good advice to the growers that you’re serving to help them know, you know, where, where they at with their, with their plant stand.
10:57
So here, here’s the steps.
10:59
I, I took this snapshot out of the wheat visual guide that’s at the IPMC website.
11:09
But we want to count the number of plants in a three foot length.
11:12
We want to do this in three areas across the field.
11:16
Take the average of those counts, multiply that number by 4, then divide by the row width in inches.
11:23
OK, so here’s an example on the right hand side for you.
11:27
We have those 3 counted areas.
11:29
They ended up with 40, 35 and 45 plants each.
11:34
Divided that by three for an average of 40, multiplied by that factor of 4 to get 160, and then divided back by the row width.
11:45
So 7 1/2, kind of a standard drill width.
11:49
So we got 21 plants per square foot, OK, and some information on the right hand side that you know you might use or you know your supervisor might use.
12:01
This is through again, Shawn Conley’s research at UW Madison.
12:06
With that, you know, plants per square foot.
12:09
OK, What is that goal that we need to reach our yield goal?
12:14
Less than 12 plants, Sean says automatic replant 12 to 15 plants, you know, maybe consider a replant depending on current economic situation.
12:26
You know, for that small grain crop versus planting another crop, 15 to 22 plants, you got a chance of meeting your yield goal.
12:36
You know, there’s some other things that need to come into play, maybe the amount of tillers that we have, you know, per per plant.
12:43
And then if we’re at that 22 plants, we should have that full yield potential for the crop for that year.
12:53
OK, I guess I’ll just I’ll pause there for just just a half second and, you know, see if there’s any questions about, you know, crop stands, why we take them.
13:08
Did I, you know, gloss over something too fast?
13:12
Do you have another technique?
13:14
I on the last slide, I can go back there.
13:18
I think 2 slides ago, I did throw in a little line there about taking a drone image and some of that work has been evaluated.
13:29
If our you know, if our software is calibrated right that we’re using, I think it can it can work.
13:36
It might be a way, you know, to get out over a larger fields, save a few steps.
13:42
But again, you know, just making sure that that work is, has been evaluated, you know, back to more of those hand type counts is a way that, you know, we really can be confident then that that, that that’s going to work.
13:58
All right.
13:58
And I, I did see a question that that came in to the chat.
14:04
Open that up.
14:04
Real quick. Question is what’s the ideal stand count for rye to take to harvest?
14:13
That is a really good question.
14:15
I am going to default to the same stand count that we used for wheat, OK.
14:26
And so if we can meet those those goals, I do think it within Shawn’s small grains guideline, there’s a little bit in the very end that talks about some of our other small grains, barley, trader kale, rye and such.
14:44
And you know, all those plants are a little bit different and there’s stand density.
14:49
So yeah, I’m going to default to that for right now.
14:51
And maybe one of my colleagues that is on if, if they know that answer, they want to put that in the chat or I will follow up afterwards to get a more exact answer for you.
15:03
Thank you for the question.
15:07
OK.
15:08
Now getting into that crops growth stage, you know, knowing, knowing this for your field matters because why does it, why does it matter?
15:20
Well, I have a few reasons here that I wanted to include.
15:24
There probably are a few others, but we’re going to we’re going to start with these for today.
15:30
So thinking about corn and soybeans, even even some of our small grains, our herbicide guidelines are very specific for what growth stage those crops can be in, all right.
15:40
So if you think about what a herbicide does, it is a product that is inhibiting the growth and actually killing, killing a plant, all right.
15:50
So when we spray that, often times we spray it on the target plant, but also on our crop plants at the same time, right?
15:58
So we’re expecting our crop plant to metabolize that that herbicide, while we are, you know, expecting that weed plant to take in that herbicide and, and cause death.
16:16
All right, they all, they all are a little bit different, but the goal right, is that we’re going to kill that plant.
16:24
They all affect different, you know, growth points within, within a plant, different herbicide modes of action.
16:32
So with that you know, knowing that crop stage where the crop can metabolize that herbicide and not have an impact on further growth and development is important.
16:45
You know, if we don’t want to cause stress to a plant at a time when it is starting to think about the yield goal that it wants to have for that for that year.
16:56
Another reason might be monitoring that crop’s growth and development.
17:01
If we have a crop that we want you know, ready for harvest at a certain time, if we are curious, you know how our crop is developing for maybe putting on another application of fertilizer.
17:15
It’s important to know what that growth stage of the crop is.
17:19
And then one of the one of the other important areas is meeting that timing for a fungicide application.
17:27
Our plant pathologist Damon Smith has done a lot of work looking at timing of fungicides for multiple types of plants.
17:35
OK, we’re going to talk about a little bit of that today, but understanding what that growth stage is.
17:41
So we can time that fungicide to protect, you know that developing plant protect either the either the seed head protect you know those leaves stores the top of maybe the corn canopy protect that flower during development of the seed pod and soybean.
18:03
Those are some reasons, you know why we need to understand the growth stages to make those recommendations.
18:12
OK, so beginning growth stage is germination.
18:16
I thought it was important to include this.
18:19
Some of our crops are are still in this stage, right, The ones that haven’t emerged yet.
18:24
So we’re going to start with corn.
18:26
Think about germination, that that first step where the seed imbibes oxygen and water, that radicle emerge, emerges and moves downward.
18:37
The coleptile emerges and moves upward.
18:40
And then later those lateral roots will, you know, start to grow away from the mesocotyl.
18:46
All right, so couple good pictures here from the corn guide at UW Madison so that we can kind of understand what that looks like underneath the surface of the soil.
19:00
Corn grow staging, though, is really based off of the leaf collars.
19:05
OK, So to have a, a fully to have a growth stage further than you had last time, you need to have that entire leaf collar, right?
19:18
So you can see that on this corn plant on the right hand side where that that leaf, it’d be that first true, true leaf that comes down to the stem.
19:28
It forms that full collar around the stem.
19:30
And you can see that on the second leaf as well.
19:33
Second leaf collar not included in this picture would be, you know, most likely the third leaf that does not have a fully developed collar.
19:44
OK, so it doesn’t completely fit around the stem of the corn plant.
19:48
So we can’t give it that extra growth stage.
19:52
So this would be a V2 or in the second growth stage.
19:57
All right.
19:58
And then on the left hand side of the screen, I have just another image there that shows that that germination and developments of that early corn seedling, that very first leaf is going to be that true leaf is going to have kind of a rounded tip on it.
20:15
But where that meets the stem that is considered the first, the first collar.
20:23
OK, another representation of this.
20:26
From a guide from the university at Purdue, you can see that going up the plant a little bit farther there in the picture on the right.
20:35
That first step, true leaf at the bottom, that’s at leaf collar one or V1.
20:41
As you go up the plants, you have V2, V3.
20:45
That 4th collar is just hardly fully formed, but that would be a V4.
20:51
And then our, our fifth collar, our fifth plant leaf is not fully merged yet.
20:57
So we can’t, we can’t give that the next growth stage.
21:00
That would be a V4 corn plant.
21:03
All right.
21:03
So if everything’s, you know, attached, well, this is pretty easy to, you know, to identify once you kind of get an eye for it, once you know that you’re looking for that leaf, but it has to come all the way back to the stem and form that collar.
21:18
OK, So corn has vegetative stages from VE, which is the emergence stage all the way up until VT, which is tassel.
21:28
OK, some important stages when yield potential is being determined V6 through V11.
21:36
OK.
21:37
So when we have that, that 6th collar on the plant, that’s when we’re starting to determine the amount of rows that are on the cob, OK.
21:47
And a little bit of an interesting fact, kind of a fun fact, kernel corn, corn ear rows are always going to be even numbered, OK?
22:00
So has to do with the anatomy of the corn plant.
22:04
So we’re going to be 12, 14,16, 18, maybe even 20 those rows.
22:10
The amount of rows really has an impact on yield and that is going to be determined through that V6 to V11 time frame.
22:19
All right.
22:19
So we’re thinking about trying to reduce stress to the corn plant at that time.
22:25
You know, hopefully we have some of our herbicide applications, you know, done before that.
22:33
That corn is actually starting to canopy at that point.
22:36
Hopefully we have our soil fertility, you know, adjusted at that point so we can let that corn crop develop.
22:44
And then from V12 to VT, the number of kernels per row and that your ear size are being de determined.
22:52
OK.
22:53
So another timing when we want to try to avoid, you know, stress to that corn plant.
22:57
If we have the ability to put some ear irrigation water on, you know, if if it’s dry, that might be reasons to consider that you know, kind of during those time frames.
23:09
Another interesting piece about the corn anatomy is that every corn plant has a different amount of leaves, OK?
23:17
So it’s somewhat based off of the relative maturity of a corn plant, but it’s also based off of that growing geography of the plant.
23:26
So for instance, maybe 110 to 115 day relative maturity corn plant might have 21 to 23 leaves.
23:35
OK, So that’ll actually have a V21, a V22, a V 23.
23:41
And then that VT is that final vegetative growth stage, whereas maybe a shorter maturity corn plant in northern Wisconsin for instance, would maybe only get to V-17 OK before it before it gets to that VT or that tassel timing.
24:00
So there’s not a, a definite number of leaves.
24:04
It can be based off of the growing conditions, based off of the genetics of that corn plant and the, you know, in that environment that it’s growing in.
24:16
OK, so this will be a little challenging to describe here virtually, but I wanted to share it anyway.
24:23
Hopefully when we get in person here in later June, this will be a really good skill that we can learn when we’re in the field.
24:30
But there’s a couple of growth staging methods for if we for if we’re in a field that’s missing, you know, that really nice beautiful bottom true leaf and collar and we can just count those all the way up.
24:45
There’s a process here where we can kind of go back in and do some further investigation to say, OK, what growth stage is this plant?
24:53
We actually have to go down to the base layer to the soil and kind of pull back a little bit of soil there and start to identify some structures on that corn plant.
25:03
So we want to look for a stem node that’s right at the surface of the soil.
25:08
This little chart I have up has a star next to representative plant.
25:13
We’ll see that in a couple of slides.
25:15
But that just means, you know, looking at picking a plant that you know, meets kind of that representative goal across the field, you know, not not picking kind of an outlier plant.
25:26
So it’s called the six leaf method.
25:29
So first we kind of clear out that space by the surface, the soil, and we’re looking for that node.
25:35
I think this picture does a pretty good job of kind of showing that that bulge or that node on that corn plant, this node is typically that 6th stem node case.
25:46
That gives us a little bit of an idea of how far along this plant is.
25:50
You know, if we’ve lost those bottom leaves.
25:52
So maybe maybe they were eaten off by insect damage, maybe they dried, dried and fell off.
26:02
Who knows what happened to them, but if those leaves aren’t there anymore, this method will help us better understand what that growth stage is.
26:12
OK.
26:12
So you might need to take a knife and kind of open that just a little bit and expose it so we can, you know, kind of see for sure what we’re looking at on that stem node.
26:23
And then once we have that identified, then we can count up from there.
26:26
OK.
26:27
So we know that that is our, you know, our six leaf collar for instance.
26:32
Then we can go up from there and keep adding leaf collars until we run out of them, you know, until we get to those newer leaves.
26:39
So that’ll, that’ll give us, you know, that corn stage of that, of that plant.
26:46
And again, that that little* there, you know, 50% or more of the plants in the field are at or beyond, you know, the size of that of that plant is what you want to try to try to measure.
27:01
OK, a little kind of confusing, but hopefully again, in person we’ll be able to explain this just a little bit more.
27:09
Another way is actually to look at that plant, you know, from the root up.
27:13
So corn staging that inner mode method.
27:16
So we’re going to dig a representative plant, actually split it open with a pocket knife, OK.
27:22
And we want to try to look at those root nodes.
27:25
All right.
27:25
That’s going to give us an idea of the the age and the development of that of that plant.
27:31
So identify that fifth stem node, OK, that’s kind of the the more dominant looking one, they’re kind of towards the top.
27:41
The internode between the 4th and the 5th usually has a little bit of a kind of a gap there.
27:48
That might be a way that kind of show that to us, we can kind of count either way and then and then count upward from that fifth stem node.
27:57
OK, to determine that highest visible leaf collar.
28:01
So again, we want to try to, you know, pick, pick uniform plants, you know, that have the right developments for getting a gauge on that entire field, right.
28:12
So we’ll we’ll take a look at both at six node method and the internode method in person.
28:19
Hopefully between now and then your fields on that you scout, will just have perfect leaf structure and you’ll be able to find that first collar and work your way up from there.
28:28
Or again, reach out or ask some questions afterwards.
28:31
We can talk through it some more, a little bit more about corn grow staging once we get into that reproductive stage.
28:39
Another important check in point is that pollination.
28:43
OK, so there’s a little bit of a trick here.
28:46
Granted, every ear of corn is important to your, to your growers, but it’s important too, to know what that pollination level is.
28:54
So a little bit of a trick here.
28:55
You can remove an ear carefully, you know, pull the husk back, you know, from that ear, you kind of want to wait till that pollen shed has stopped, maybe two to three days.
29:06
Once you’ve, you know, carefully pulled those husks back and you can, you can shake that ear.
29:11
OK, Any of the silks that fall off, that’s a good sign that they actually pollinated so that that little ovule was actually fertilized.
29:23
If the silks are going to stay on there and retain on there, well then that’s kind of a sign that those kernels did not become fertilized and they will not develop any further.
29:36
OK.
29:36
So a, a way to get an idea on that pollination, you know, across the field, you know, as one of the more important stages of corn production, reproductive stages are from R1 to R6.
29:51
You know, that corn plant actually is in a VT and an R1 stage simultaneously during pollination.
29:59
All right, that that the tassel is producing that pollen while we have our ear development in the R1 stage accepting that pollen and then that that really critical stress period of time 14 days before and 14 days after R1.
30:14
So it kind of catches some of those later V time frames, vegetative time time frames and then, you know, into that R1 time frame as well, trying to avoid crop, crop stress again at that at that point.
30:32
OK, finishing up on corn, the six reproductive stages, I just, I think it’s interesting that, you know, once we hit that silking or we hit that tassel timing, we really can start to predict, you know, when that crop is going to be, you know, at maturity.
30:53
So I think it’s important, you know, as you’re scouting those fields to kind of mark, mark some of those timings down in case the grower has questions, you know, late later on.
31:03
Hey, when did that, when did that field tassel, when did that field start Silk, That can give us some, some pretty good guidelines here based off of the research data that we have.
31:13
And it’ll be roughly this many days before that corn reaches that black layer stage, OK.
31:18
And the black layer is that physiological maturity stage of corn when that when it starts to dry down, it isn’t taking any more nutrients in and moisture isn’t leaving back into the stem so that the crop is starting to dry down, OK.
31:39
And a look at this maybe from like a corn silage standpoint, OK, looking at that ear and how those kernels look R1 through R6 kind of an important fact as well as we really, you know, need to wait until that corn kernel, that corn ear has developed and reached about that half.
31:58
Milk layer
31:59
You can see how the total dry matter, how it just explodes from early R5 where it’s at 45% dry matter up to that mid R5 where it’s at 90% of total dry matter, OK.
32:12
So really a lot of extra yield, I guess I’ll say, you know, for that salvage crop, if we can allow that starch to dry, it’s a little bit more in the field.
32:21
Again, follow all you know, you’re a little bit too much information maybe for some of some of your work here this year, but some interesting information as you build out your skills moving forward.
32:34
OK, a little bit on soybeans, pick the pace up a little bit.
32:38
So again, they go through that germination process, the imbibes water, the radicle forms, the hypocotyl elongates, but it’s a different plant, right?
32:49
So it’s not going to push that stem out like the corn plant does, is actually trying to lift that entire, you know, seed up to the surface of the soil so those cotelydons can open up and form the first leaves.
33:03
OK.
33:03
There’s a couple of methods here for doing that soybean grow staging.
33:09
I just wanted to kind of share that within Sean’s guide that I pulled all these snapshots out of.
33:16
He, you know, he, he talks about the difference between kind of the node method and the leaf method or that trifoliate leaf method.
33:29
OK, so grow staging field, we want to take you know, into account different places within the field.
33:35
The recommendation here is to pick five different areas.
33:38
I think that’s a pretty good number on the low end.
33:41
You know, if you if you pick a few more, I think that’s I think that’s fine.
33:45
But determine the growth stage of those of those areas.
33:49
You know, pick at least 10/10/10 plants in each area and make and make a little bit of a chart.
33:54
You know, is it at V3, is it at V4?
33:57
What’s what growth stage are those plants at?
33:59
And that can help give you a field average.
34:01
I think a good technique for when we are doing other crops as well.
34:05
You’ll have some type of a table set up and keep track and try to get that average from across the field.
34:13
Here’s what some of those early growth stages look like for soybeans.
34:16
So on the left is that emergent stage OK, that cotyledon is hitting the surface of the soil and opening up.
34:24
And that growing point is there.
34:27
That VC is the that first unifoliate leaves.
34:32
OK.
34:32
So that next step right after the cotyledon, you can see there’s a first leaf node is present at that time, but it has not reached the leaf stage yet until a full trifoliate opens.
34:46
OK, so this is actually V1 soybean.
34:50
So we have those cotyledon leaves down at the very bottom.
34:53
You can see those there, that first leaf node where those first true leaves opened up and then we have our second leaf node followed by those trifoliate leaves, which makes this a V1 plant OK.
35:09
And there’s some there’s some other information there.
35:12
Again, this is all within that soybean growth guide, some really good information, you know, presented in a way that I think is pretty, pretty straightforward to understand.
35:22
V2 we have some of those similar, you know, features there with the different leaf nodes, but then we have that second full trifoliate that’s open.
35:33
V3 is, you know, again has the first trifoliate, the second trifoliate, and we work our way up that stem.
35:41
Then that third trifoliate opens up, OK, hits that V3 growth stage again.
35:48
You know, important to know if we’re putting different herbicide products out on the field, these early growth stages for both corn and soybean, you know, are those plants going to be able to take in that herbicide and metabolize it and not ’cause injury to the plant?
36:04
And I have the…
36:06
After V3, because you know, we, we learned that a corn plant can have different vegetative growth stages.
36:14
Soybean plants are the same.
36:15
They actually can have almost infinite number of vegetative growth stages.
36:19
And there’s a lot of reasons why.
36:24
But anyway, we can’t really put a true count on that.
36:28
It’s it’s V3 to to whenever the plants start to flower, OK.
36:32
And that’s at this R1 stage, all right.
36:35
And this is one of those first stages where, you know, if there’s been some white mold risk, you know, in that field or if maybe we have a soybean variety that is susceptible to white mold, this would be one of those first timings that we may consider a fungicide application.
36:54
Again, utilize some of those tools that that Damon Smith, our plant path pathologist, has put together.
37:02
He has some tools for both soybean and corn that help us gauge, you know, are the weather conditions right for needing a fungicide application.
37:13
We might have the plants in the field.
37:15
We might have the plant at the right stage.
37:19
You might have the disease risk.
37:22
But if the weather conditions aren’t there, we may not, you know, see that disease risk in our in our fields.
37:28
Damon always talks about that as being the disease triangle.
37:31
So we’ll learn more about that in future in future talks.
37:36
V2 simply means that there is, you know, there’s, there’s more open flower nodes, you know, on those on those plants and flowering can continues.
37:48
It’s based off of day length and whether the plants, you know, have a determinate growth type or indeed, indeterminate growth type.
37:59
V3, the next growth stage there actually it was one of those later reproductive growth stages as far as, you know, us being able to really put out any type of a crop protectant, you know, on those plants to help reduce that risk of that white mold spores, you know, getting getting into the flower and affecting the development of the of the soybeans.
38:28
So just you know, kind of kind of knowing our window is kind of at R1 to R3, which can be, you know length of time is not definite, but that’s kind of our window to protect that soybean seed, that soybean yield in our field from white mold.
38:47
Just a picture I thought was interesting looking at that development of the seed pod, you know through more of those later stages, R3 through R6.
39:00
OK.
39:00
And a little bit on wheat.
39:02
So, so spring management, which we already took care of this year, we’re pretty much past that, that green up is that Feekes 3 or Feekes 4, OK.
39:11
So often times like our wheat that’s planted on time will actually reach a Feekes 3 in the fall before winter before it goes through the vernalization period
39:22
So when it starts to wake up or green up in the spring is going to already be at Feekes 3 pretty much and hits Feekes 4 pretty soon.
39:30
So that’s a good timing for doing one of those stand counts, a good timing for nitrogen app application and a good timing to be thinking about any weed can control that we might need in the field.
39:41
OK, so there’s some further study that we can learn about the amount of tillers on a wheat plant.
39:47
This picture I thought showed that pretty well.
39:50
We have that main shoot.
39:51
So that’s that main plant that came from the seed that we planted last fall.
39:56
But then these tillers have developed tillers in small grains are positive.
40:01
Tillers in corn are maybe not really a positive.
40:06
OK.
40:06
We’re we want that corn plant to focus on that one, that one stem and maybe one or two ears we want this wheat plant that will actually the tillers help us.
40:15
Those are extra growth points, extra places for yield to develop on that on that plant.
40:20
So there’s some things to think about.
40:22
You know, not just the amount of plants, but the amount of tillers that are on the plants as well can maybe affect our stand counts for for small grains.
40:35
This V5 or not a V5.
40:38
Excuse me, excuse me.
40:39
This Feekes 5 point is when that head is starting to push up through the stem, it’s a point when that plant becomes a little bit, it comes risky to do, you know, many herbicide applications, it becomes risky to to drive in the field very much.
40:57
So you want to try to have, you know, any of any of that work done ahead of time so we don’t injure that plant because it actually won’t be able to grow back, you know, from injury when it’s at this Feekes 5 stage, since that head is starting to actually emerge above ground and, and get up into that growing stem of the plant.
41:18
Sorry, wrong way.
41:20
And again, you can open up that stem of the plant and you can see these different growing nodes.
41:24
OK, It’s kind of an interesting way to see, you know, where that where that head is actually at and those different growing nodes.
41:32
Feekes 8 is a flag leaf stage, may or may not, you know, be reason to think about a foliar fungicide.
41:39
It really depends on the the year, you know, if you’re helping to advise some of that, you know, connect with our specialists at UW Madison be looking for some of that information.
41:53
This isn’t an every year kind of recommendation, but this is kind of timing to protect that flag leaf, which really helps with the yield potential of that of that small grain plant.
42:08
Did it again.
42:09
OK.
42:10
And then one of the more important growth stages though in wheat is this Fusarium head blight stage, OK or this Feekes 10.5.
42:20
So that’s really the stage when the flour start to come out of that head.
42:24
And this is common for you know for other small grains as well.
42:27
We have kind of a small window that five to seven days from when that flowering be begins when we can put a fungicide product out there to help protect that plant from Fusarium head head head blight.
42:41
So something that you know to talk with our growers and to have them be aware of that.
42:46
The window is kind of small, but this is a research type window that that we know we can really make an advantage to the the quality of the grain if we can, if we can hit this timing right.
43:00
OK, I’m going to skip the last stage there.
43:03
It just talks about that kernel, that physiological maturity of that wheat kernel and then the dry down that happens.
43:11
All right, a little bit about soil sampling.
43:13
I, I can see I maybe haven’t left myself enough time.
43:17
So I apologize if you were mostly here for the soil sampling part, but this this may be something that you’re still doing in a few fields, maybe growers that have picked up some new acres for this year, you know, or maybe you’re just going in because it didn’t get sampled last fall and you want to get a sample this spring.
43:36
All right, so we want to sample to three quarters the depth of tillage.
43:40
So if we’re planning like a nine inch chisel plow depth, that’d be like 6 and three quarter inches is your sampling depth.
43:48
No till kind of that six to seven inches is the recommended depth.
43:53
OK.
43:53
So kind of get yourself Cal calibrated know know where that depth is on your soil, on your soil probe, you know, so that we’re sampling to the right depth.
44:05
Just a little note if we are kind of curious or think our soil pH might not be quite in line and no till, we want to take that zero to 2 sample there to get a more accurate pH sample.
44:19
But we want to take 10 cores equal 1 sample.
44:23
OK.
44:23
So 10 pushes of the soil core into the ground, 5 acres Max per soil sample.
44:29
You can sample less, you know, if you want to sample more frequently and then they’ll collect those samples from representative locations in the field.
44:38
So for instance, on the right hand side here of the slide, there’s a 15 acre field we’re kind of sampling.
44:44
We broke that up into three kind of general areas and we’re sampling, you know, 10 times across each of those three areas.
44:53
So we’re going to collect, you know, 30 sample cores.
44:57
Those are in three different samples.
44:59
And we might, you know, this might be 1 field though.
45:02
OK, so you’re going to have three soil samples for one field.
45:06
But if it’s all managed the same, when we fill that out in that soil submission form, we’ll, you know, we’ll get an average, we’ll get a combined result for the entire field, which is normally how we make the recommendations then for the next four years.
45:26
OK, so that routine soil test, this is a sample sheet for UW Madison for the soil and forage lab.
45:33
You know, work with whatever lab is convenient in your part of the state, you know, fill out the submission form as accurately as possible.
45:42
If you do so, you know the some recommendations will be given back and these are the same recommendations that you’d get through A2809, which is our soil sample or our soil application guidelines for Wisconsin.
45:58
The same information that’s within the SNAP Plus program and really the information that, you know, we want to be giving growers as crop consultants, you know, that really meet that meet that spot between, you know, meeting our yield goals, but also not causing, you know, extra nutrients being placed in the landscape.
46:19
OK, So those profitable for fertility recommendations is what is what you’re going to be getting back.
46:26
We need to include the soil name, the crop rotation, the yield goal for that crop, any legume or manure credits that are present in that field.
46:36
Those are all information pieces that will help us get the most accurate fertility recommendation back from the soil lab.
46:45
So nitrate tests, you may be, you know, doing some of those here pre plant or pre side dress.
46:52
So these are a couple of soil nitrate tests that are available.
46:55
It has its own form.
46:58
So, you know, make sure you print that out separate or have that available when you’re taking those samples.
47:06
You’ll need the field ID, sample number, crop, some crop information, soil names, soil organic matter and your application history for the PPNT, not as much for the PSNT.
47:19
OK, That is just feel that ID and that sample number.
47:23
Use something that you know gives you or gives the grower or your manager, you know, the information they need.
47:31
Then to get back to that, to that right field, you know, figure out what you want to call those fields sample numbers, you know something that works for you.
47:41
For the PPNT, we actually are going to collect a zero to 1 foot sample and then a one to two foot sample.
47:48
All right, So you may need a specialized soil probe, you know, you can extend down deeper into that soil profile.
47:56
We’ll want to collect 15 cores from a field area up to 20 acres in size.
48:02
OK, so that means 15 soil core is zero to 1 and 15 soil cores 1 to 2 foot.
48:08
If you’re really feeling ambitious, you can collect 2 to 3 foot soil cores.
48:14
Usually we don’t recommend that just for the amount of extra effort that it takes and that can be estimated at the lab.
48:23
OK.
48:23
So if we have a good sample of 0 to 1 foot and a good sample of 1 to 2 foot, we can then estimate the nitrate content in the two to three foot portion of the soil.
48:34
We’ll want to sample in the spring ahead of any nitrogen application.
48:40
And on the right, right hand side, it just kind of talks about how we use that information to make a recommendation.
48:47
I’m not going to talk about that today, but it will be within the slide set that you’ll have access to. A pre side dress nitrate test.
48:55
So a little different timing here.
48:57
We’re sampling the V3 to V5 growth stage.
49:01
OK.
49:01
So another I guess reason to kind of know what our growth stages are is for our fertility application and the sampling again, 15 cores from across the field area up to 20 acres in size.
49:14
So if your field is 10 acres, you you can still pull 15 cores.
49:18
If your field is 40 acres, you’re going to want to pull 2 separate samples, OK.
49:23
Sampling depth though is just zero to 1 foot and sample between the cornrows.
49:28
OK, So this is getting an idea.
49:30
So we might have put some fertilizer out already early or we put some manure out early.
49:38
This is getting an idea of what the what’s been broken down through this organic matter to the nitrogen cycle and is available now to our growing crop.
49:49
A little bit about tissue sampling and again, I, I apologize, we kind of have to rush through this a little bit, but we’ll have a chance at the in person meeting to talk about this.
50:01
More. Reasons for maybe taking a plant tissue test, you know, gauge the level of crop nutrient uptake, confirm a nutrient deficiency, diagnose a nutrient imbalance.
50:14
If you suspect A nutrient deficiency when you’re pulling these tissue samples, it is a recommended, recommended approach to also pull a routine soil sample at the same time.
50:26
OK.
50:26
So within a similar area of the field gives us a chance to, you know, better understand is this deficiency we’re finding in that growing plant part of lack of not having those nutrients available or or is there something within the plant that’s not allowing them to be taken up?
50:45
Right.
50:46
And this is a chart that is within every plant tissue sampling form.
50:53
It’s usually on the backhand side, but just gives us an idea of what part of that plant we need to sample.
50:59
OK, so for instance, for a corn that is 12 inches, which they really should have a growth stage there.
51:06
But anyway, 12 inches is probably that V4 to V5 stage.
51:14
We want to actually sample the entire plant and sample 10 to 15 plants.
51:18
OK.
51:18
So again, every plant is important to the grower, but if if it is, you know the goal of getting some plant tissue analysis, we do have to sacrifice a few plants for the betterment of the field.
51:33
Apologize.
51:34
OK.
51:34
And this is the submission form, what it looks like for the plant tissue test at the Wisconsin lab.
51:41
Again, it might be different at other labs, but contact information, payment information, sample ID, crop name, stage of growth, plant part, field appearance and then was a complimentary soil sample submitted.
51:56
OK, just some basic information that you’re going to want to have.
52:00
OK resources in just a couple slides here are left again.
52:05
We’ll some of this has been shared out during the talk.
52:09
I do suspect we’ll have a pool of resources that we’ll put together that will be available at the in person trainings.
52:17
You know, a, a, a big set of information that you know, can be for you to have a few credits here where I grab some of the snapshots and such, some of the graphs for my talk.
52:32
One thing that I wanted to just share, I guess as we finish up for today, is that, you know, really think about that soil sampling or plant tissue sampling ahead of time.
52:45
It, it makes a lot of sense if you, if you can sit down, you know, at the office before you head out or, or wait in the truck before you head out and get all of your soil sample bags labeled.
52:57
Know what size of fields are you’re headed to.
52:59
So you know how many sample bags to prepare and bring.
53:03
Throw a few extras in.
53:06
Occasionally something happens where a bag will rip open or maybe there’s a bag that you know has an issue to begin with.
53:13
But have those labeled ahead of time.
53:15
You know, labeled in the way that works best for you with your manager’s guidance, works best for the grower because that really is important work that you’re doing.
53:25
It’s hard work and important work.
53:28
And having that labeled well can really help when you get that data back to be able to connect that back to certain fields.
53:35
With that, thank you for attending.
53:39
We’ll look for another inch of rain maybe next week around Tuesday night, Wednesday morning.
53:44
So you can join us again next week.
53:47
And I’ll stay on if there’s any other questions.
53:49
If I miss some in the chat and you want to and you want to talk some, I will hang on.
53:54
Thank you for your time and attention.
Foundational Crop Scouting Training
Providing crop scouts with the key foundational skills necessary for successfully scouting field crops including corn, soybeans and alfalfa.