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Mike Howell (00:08):
The Dirt. With me, Mike Howell, an eKonomics podcast where I present the down and dirty agronomic science to help grow crops and bottom lines. Inspired by ekonomics.com farming’s go-to informational resource, I’m here to break down the latest crop nutrition research, use, and issues. Helping farmers make better business decisions through actionable insights. Let’s dig in.
(00:39):
Well, hello again everyone. Welcome back to The Dirt. Hope everybody’s getting plenty of rain as we’re moving into this production season and the crops are off to a good start. We have Dr. Karl Wyant back with us today. Karl, if you would, I know you’ve been on several times in the past, but if you would, introduce yourself to our listeners again. We may have somebody new joining in that hadn’t heard about you yet.
Dr. Karl Wyant (01:00):
Hey Mike. Thanks for having me back. Happy to be here. I am the Director of Agronomy here at Nutrien and I live out west. I live in Arizona and I came up in the California/Arizona ag production areas and have had lots of interesting experiences here with the intersection of what you’re putting in your spray tank and the water that you’re using to mix it with. I’m looking forward to our chat today.
Mike Howell (01:23):
Well, Karl, back when I first started, we would get water wherever we could get water. That may be a public water system or it may be pumping it out of the creek or a ditch bank if we happened to have one close. It really didn’t matter as long as we had enough liquid to mix our pesticide with it and get it put out. But I understand there’s a lot of things that have changed and that people are taking a different look at the quality of your water source. What are some of the main quality indicators that somebody needs to consider before making a pesticide application or a fertilizer application?
Dr. Karl Wyant (01:53):
Yeah, you’re right Mike. You can get your water from just about anywhere. That could be a real challenge. Some water sources are super clean, some of them not so much, and I’m looking at the folks that are pulling their spray water from dugouts that they have on their farm and comes out looking like chocolate milk. So there’s a couple pieces of data we can actually use to look at water quality and those categories are water hardness, bicarbonate, the pH of the water and the turbidity of the water or how cloudy that water is. We’ve got just a couple of data points to use that we could actually look at and predict how that water source, wherever you get it from, how that water source might actually interact with your favorite crop protection material.
Mike Howell (02:33):
Karl, you threw out a lot of big words there. I know what pH is, but I haven’t done a lot of time looking at the pH of the water. But start with your list and define each one of these indicators and maybe give some parameters around what’s an acceptable level, if that’s possible, with each one of them. Let’s start with water hardness and tell us what water hardness is and how we measure the water hardness.
Dr. Karl Wyant (02:55):
Sure. Water hardness. Folks might be more familiar with that term if they have a water softener at their house, and what that water softener is doing is removing positively-charged ions like calcium, magnesium, iron from the water itself and making sure that you have a better experience when you’re doing dishes or what have you. Farmers have to worry about water hardness because of the charges of those ions. They can actually go into your crop protection active ingredient and start rebinding with the active ingredient like glyphosate and rebind them and twist those active ingredients into a shape so that they no longer work and you as a grower get less efficacy and the performance of the product is worse off than if you didn’t have that water hardness.
(03:39):
So sadly, you can’t see it. You can’t just look at the water and be like, “Oh, that’s hard water. That’s soft water.” It all looks like water, but what you can do is test for it, spray water sample. Typically what we like to see is water hardness below 80 to 100 parts per million. When you start getting up over that, that’s when you can have some really nasty interactions and it’s really tough to say who has the hardest water in the United States and Canada, but there’s some nasty stuff out there. I’ve seen reports of 500, 600, 900 parts per million and we have to deal with it. It can be a real challenge and like I said, something you can’t see just looking at your water, you got to measure it using your lab equipment.
Mike Howell (04:20):
Okay, I think the second one you mentioned was bicarbonate. What do we mean when we’re talking about bicarbonates?
Dr. Karl Wyant (04:25):
Bicarbonate is a type of carbon that can be in your water. You have CO2, you have bicarbonate and you have carbonate. You have three species of CO2 and it’s highly dependent on the pH of your water. When you have a slightly alkaline water, you can have a lot of bicarbonates and that can be a challenge because that bicarbonate can bind with active ingredients and cause them not to work real well. If you want to think about bicarbonates, especially those bicarbonate levels above 400 parts per million, think about your dims. That’s sethoxydim, clethodim, tralkoxydim. And all the chemists are going to make fun of me for how poorly I’m pronouncing these. Also on that list is 2,4-D. They can make it hard for that product to work.
(05:10):
Another piece you have with your bicarbonates is that they like to resist pH changes, so the pH is a measure of how alkaline or how acidic your water is. In a perfect world, your spray water quality would be slightly acidic to neutral. That’s not the case though. Some water is very basic. It’s almost like oven cleaner. I’ve seen reports of 9.2. We’re shooting for like a 7 or a 6 all the way down to somewhere acidic water. When you have high bicarbonates, you try to drop your pH of your water and that bicarbonate will resist the buffering, the pH drops. You got to add a lot more pH adjustment product to make it all work. So it’s a nasty little guy. I wish all of our waters were below 100 parts per million on bicarbonate, but that’s not necessarily always the case.
Mike Howell (05:54):
Karl, you mentioned pH there talking about bicarbonate, and I’m sure pH is going to have other roles as well is why it’s on our list twice. Talk a little bit more about pH and why that’s so important.
Dr. Karl Wyant (06:06):
PH is just like soil, one of those strong determinants of how things are going to behave in a spray mix. Particularly we will focus on the alkaline side of pH. PH is a water above 7 and I mentioned earlier I’ve seen a report of 9.2, just really alkaline water. That farmer should be selling that water at the store for lunch money, some fancy spa water or something. But when it’s that high of a pH, something that can happen is this phenomenon called alkaline hydrolysis, and it’s where the high pH of the water actually starts cutting your active ingredient apart and those active ingredients, they lose their ability to perform because of the alkaline hydrolysis, that cutting, the lysis part is actually really just destroying the actual active ingredient. Now, not all active ingredients are susceptible to this alkaline hydrolysis.
(06:57):
That’s why a lot of people try to move their water down so they can avoid that alkaline hydrolysis issue. But if you do run into this, there’s some products that are super sensitive. We have this thing we call alkaline hydrolysis half-life, and it’s the amount of time that it takes for half of that active ingredient to lose half its strength at a certain pH. There’s some products that you go to a pH of 9, they’ll lose half their efficacy in about 15 minutes. That’s how quick it is. That’s how bad it can be. Not all products are like that. Some have the same rating, same conditions all the way out to a month, three months, so you really don’t have to worry about it. It’s really product by product, active ingredient by active ingredient, and therefore to fix that, a lot of growers just drop pH automatically.
Mike Howell (07:42):
And the last thing you mentioned was turbidity. What is turbidity when we’re talking about spray water solutions?
Dr. Karl Wyant (07:48):
I want you to picture a glass of clear water. That’s low turbidity. And then think of a glass of your favorite hazy IPA beer, right? You’ve got two glasses, low turbidity on the clear water, high turbidity on the hazy IPA. We see spray waters go out because finding that water, you might not have a lot of options like we talked about earlier. You might have to get it out of this ditch. That’s the water. It could be really dirty and when you have all that stuff in the water, it can actually bind with the active ingredient and render it not so useful.
(08:19):
Turbidity is a tough one. If you can let your water source settle before you start pumping it into the spray tank, that’s a good way to reduce turbidity. Just pulling off that top couple of inches if you can. A nice way to measure it if you have high turbidity without spending a lot of money, get a five gallon bucket, white one, and fill it up with your water source. Drop a quarter in. If you can see the quarter at the bottom, you’re in good shape. If you can’t, you’ve got high turbidity water and you need to manage that a little bit differently.
Mike Howell (08:46):
Here on The Dirt, we’re dedicated to offering the best agricultural knowledge. I’m happy to share that three CEU credits are now part of that offering. Check out the available podcast CEU credits and other learning opportunities by visiting nutrien-eKonomics.com and clicking on the agronomics tab.
(09:09):
Karl, we’ve talked about all these different factors and I guess maybe before we started doing all of that, we maybe should have talked about how an applicator can know what the levels are. How can we test this?
Dr. Karl Wyant (09:19):
Yeah, so we mentioned these levels and this is where the utility of getting your water analyzed by a reputable lab. The lab should have something that’s called irrigation spray water test or the irrigation water test or the spray water test. Some of them combine that into an irrigation and spray water test, something like that. And what you should be able to do is go to your water source, let it run for a couple minutes just to clear out some of the stuff out of the pipes and then fill up a clean bottle please, not a Dr. Pepper bottle that you just emptied, and then take it to the lab as quick as you can. Don’t let it roll around in your truck for a week. We’ve all been there.
(09:54):
Get it to the lab and they should be able to say, “Hey, here’s what’s in your water”, and hopefully they’re not just giving you a bunch of numbers. Hopefully they’re giving you an interpretation like, “Here’s your water pH. Here’s its potential to interfere with your spray water mixes” and things like that. They’re not super expensive if you kind of think about how many acres that water source treats. I did some math one time with a grower saying, “Hey, if we take this sample and we know this water source treats about 1,200 acres, now we’re talking about pennies per acre input on just the cost side”, so it can be very economical. It can give you a lot of data.
(10:29):
Just make sure you either have a good friend nearby that can help you interpret the data or the lab provides it back to you in a way that you can get something out of it because there’s a lot of good water reports out there. There’s a lot of them that are also just a bunch of number barf and people will look at it and they say, “I don’t know what this means”, and they don’t use it. It’s a challenge. Presentation of data is always a challenge.
Mike Howell (10:48):
Does no good to get the data if you don’t know how to use it. Karl, many of our listeners are accustomed to using the soil testing lab. Can these type labs also test our spray water sources?
Dr. Karl Wyant (10:57):
Yes. A lot of the labs that you’re sending your tissues to or your soil samples to can also test your water. Just give them a call or maybe flip the page on the test ordering form and there might be a water test sitting right there. You just maybe haven’t checked that box until now.
Mike Howell (11:12):
So Karl, you’ve talked about some of the problems that we can run into if we’re using some poor quality spray water. I guess the next logical question is how do we fix these problems? Are there some solutions to this? Going back to my graduate school days, one of the things I was looking at was buffering the pH of the spray water with some insecticides, so I know that we can put some buffers in there and keep that water pH from changing. But can we actually change the pH if it’s too high or change the turbidity or other factors? Is there’s some products that’ll help with that?
Dr. Karl Wyant (11:41):
Yeah, that’s a good question. One place when I’ve worked with growers on this water issue is they’ll have multiple water sources on a farm and we take water samples from each and the exercise is to go through the chemical and physical data of the water. What we start doing is saying, we don’t fill our spray tank from that well. That’s just plant water. The crop water. That is not for filling tanks because it’s just so nasty. And then we find the well that tends to give the best quality of water and we just try to change the water source. I know that’s not always possible, but it’s a place to start, just knowing what’s in your water and if you do have better options because you might have a better option just a few fields down the road depending on how you fill up.
(12:19):
The other part is products, and that’s where you have the pH buffers where you can drop the pH and that’s good for waters that have a pH challenge, but it doesn’t really fix the hardness of the water or the turbidity of the water. The nice thing about changing your pH is that bicarbonate is tied to it. There’s this interesting chart, just in case you need to learn a random phrase for the day, the chart, it’s called the, and I’ll try to pronounce it. The Bjerrum plot and this is a fact that you’ll probably soon forget, but the Bjerrum plot shows how tied bicarbonate levels are to water pH. At slightly alkaline water pHs, you have really high bicarbonates, but as soon as you start dropping your pH like you would with a pH buffer product, your bicarbonates go with it. It drops with pH. So if you fix your pH, you’re going to fix your bicarbonates. It’s a really nice easy two for one.
(13:08):
We still have the water hardness and that’s where you have products on the market that not only impact the pH and by extension the bicarbonates, but they also impact the water hardness. They tie up those ions that are floating around that can bend your glyphosate or other weak acid herbicides into stop signs and impact their ability to kill weeds. There are some good products. I always like to say, start with the data and let it point to you what exactly you need, how much you need, and then have that next conversation.
Mike Howell (13:36):
Now, Karl, I know by and large people use water as the carrier for a lot of pesticides, but in some cases we’ll use fertilizers as a carrier for pesticides. Is there any “watch-outs” when we’re looking at things like that?
Dr. Karl Wyant (13:48):
I think when you’re using the fertilizer to carry the pesticide, that’s where really having that understanding, reading that pesticide label in a thorough manner because you might be adding two things together that shouldn’t go together either from a safety standpoint, it could make some byproduct that could cause some headaches, or you’re adding in, let’s just say go back to our micronutrient example. You’re adding in a fertilizer product to say your glyphosate and you’re inadvertently tying up that glyphosate because you’re increasing the water hardness. You’re increasing the hardness of that environment that the pesticide needs to work through. You can introduce some challenges. And so having that plan and knowing these different properties that we’ve discussed today can shed some light on maybe some performance issues you might be seeing.
Mike Howell (14:32):
Okay, Karl, well, you’ve given us a lot to think about and I hope our listeners are going to take another look at their water source before they start making these pesticide applications in the crop this year. Anything else we need to discuss before we move on?
Dr. Karl Wyant (14:45):
No. I think just for sampling, make sure you commit to that once a year. Right now is a great time to grab a water sample as we get going into the planting season. Know what you’re working with over your spray season and if you do see some changes in your performance, go back and take another water sample, see if the water’s changed. That can be quite a surprise to folks to see how water chemistry is dynamic over time, especially if you’re tied into a reservoir, an aquifer like a well or some other water source that tends to be a little more subject to nature.
Mike Howell (15:15):
Okay, Karl. We really appreciate you taking time out to visit with us today. I know our listeners have got a lot out of this. Now, Karl, I know you’ve got a website that people can look at and get some more information. Can you share that website with our listeners?
Dr. Karl Wyant (15:27):
Yeah. There’s a great resource that’s offered up by Purdue and their extension team. It’s document PPP-86. I know that’s meaningless, but the title will really tell you what you’re looking for. The Impact of Water Quality on Pesticide Performance. If you want a deeper dive after you listen to this session, I highly recommend you check out that link and you’ll see exactly how these water quality parameters we mentioned today can have a big impact on how your crop protection program is going.
Mike Howell (15:58):
Okay. Thanks a lot, Karl. Listeners, I hope you enjoyed the first segment of today’s show. If you did, please take a minute and give us a rating on your favorite podcast channel or app and give us some feedback as well. We want to hear from you to help make the show even better and don’t keep it to yourself. Please share these episodes with coworkers, family, friends, anyone you think may benefit from the information we’re sharing here. Don’t forget to visit our website, nutrien-eKonomics.com to help find the latest crop nutrition news and research information as well as market updates, a growing degree day calculator, a nutrient use calculator, a rainfall tracker, and much, much more. It’s all at nutrien-ekonomics.com.
(16:45):
Most episodes of The Dirt are now available for CCA credits. Visit our website and click on the agronomics tab to find these CCA credit opportunities and if you have a question, you can ask one of our agronomy team members. Simply ask your question and one of us will get back with you. Thanks for listening. Now, Segment 2 of The Dirt.
(17:08):
Listeners, welcome back to Segment 2. As you know by now, we’re spotlighting different research farms across North America and today we’re traveling to the great state of Florida. To help us spotlight a research farm in Florida, we have Dr. Barry Tillman with us today. Dr. Tillman, welcome to The Dirt.
Dr. Barry Tillman (17:24):
Thank you. Glad to be here.
Mike Howell (17:25):
Dr. Tillman, if you will, tell us a little bit about yourself and what you do and what research farm you’re going to be talking about this morning.
Dr. Barry Tillman (17:31):
Sure, Mike. I am a peanut breeder. I’ve been breeding plants for about 25 years now. I started out actually in rice in Texas and the parts of the Southeast where rice are grown, through Arkansas, Louisiana and that area. Now I work in peanuts, specifically in Florida. In the Panhandle of Florida, the University of Florida has a couple of research stations. The one I am located in is the North Florida Research and Education Center. It’s located in Marianna, Florida, just not far off of Interstate 10 in Jackson County.
Mike Howell (18:00):
I know that experiment station well. It goes back to my peanut days at Mississippi State and we brought farmers over to come to the field day there at Marianna multiple times. Always learned a lot at that experiment station and glad we’re able to talk about it a little bit today. Dr. Tillman, if you will, tell us a little bit about the history of the station there in Marianna.
Dr. Barry Tillman (18:18):
Sure, yeah. It goes back to just after World War II actually. This was a, maybe a lot of stations like that around North America, it was a air force base. It was Graham Air Force Base, and as it was decommissioned after World War II, acquired by the state, at least part of the land was acquired by the state for different purposes. Actually, the Marianna Airport is on part of it today. It’s a little municipal airport and we own part of it as the research station for ag, and there’s another state agency that owns another part of the land, so it was a big air force base. Originally there was an agronomist here that had just a small station. He did trials with soybeans and corn and other crops in the area and it’s grown over the years.
(18:54):
Now we have actually five faculty members at the station. Myself in peanut breeding. We have a forage breeder. We have two animal scientists as well and another forage agronomist so the station’s grown quite a lot. We have about 18 graduate students who are working here at the moment on various projects, either master’s or PhD programs. We have a dorm on the facility. So we’ve actually outgrown our facilities considerably given the way that our personnel have grown over time. We’ve been very successful in grants and research and extension program. From a very small beginning in the late ’40s until today, it’s grown considerably in its research capacity.
Mike Howell (19:32):
Dr. Tillman, that’s quite a history there, and I have been on several research farms that, as you mentioned, were part of the military bases in the past and some of those are quite unique in what they can do there. I think of Marianna and I think of peanuts naturally because that’s what I was interested in, but I know y’all do work with a lot of different things. Talk a little bit about what kind of research is going on there at the station and if there’s some outstanding accomplishments, highlight some of those from the past.
Dr. Barry Tillman (19:57):
Yeah, so I’ll start a little bit with the peanut side of it because that was for a long time the primary program here at the station was peanut breeding. My predecessor Dr. Dan Gorbett was here from 1970 until I came in 2004. So the breeding program has been ongoing at Florida for over a hundred years now. We’ve released many cultivars over that space of time and continue to run the program towards cultivar development and developing new varieties for farmers that have better disease resistance, higher yield and what have you. But in addition to that, around 2000 is when we added a beef unit to the Marianna site, and that added about a thousand acres of land, and the other faculty members, the other four besides me who are here, are all working in the beef and forage industry.
(20:39):
There’s some unique facilities here associated with that that I’ll mention. One is called a feed efficiency facility where they have unique feeding stations where they can measure the amount of feed that a cow takes in each bite, and that cow has a radio tag in its ear. They can measure the feed intake as well as the weight gain from that animal on the feed that they eat. That’s a unique thing. They also do what’s called a Florida Bull Test, where they bring in consigned bulls from growers around the area here, and they do physiological and genetic tests on those bulls to determine their fitness, and then they sell those bulls in an open auction. That’s another program of the beef unit side.
(21:15):
Of course, there’s also forage work going on. Obviously cows eat forages, and so the forage breeding effort just hired a brand new faculty member here a few months ago replacing a long-tenured program, excited about having someone here to ramp that program up. Also a forage agronomist who’s looking at integrating legumes into bahiagrass pastures and shown some really good promise there. So I think there’s some really exciting things coming out through those programs in addition to the peanut breeding, in the forage and beef area too, in these programs.
(21:44):
They’re looking at also methane reduction. As you know, that’s one of the greenhouse gases that is of high interest. Looking at ways that they can feed cattle different things to reduce methane, so a lot of things going on here for a small station. A lot of activity, a lot of people, and a lot of research and extension activities going on.
Mike Howell (22:01):
A lot of great work it sounds like, as always. Dr. Tillman, I mentioned earlier that we always came over for the Peanut Field Day. Do you have a date set for the Peanut Field Day yet for this year?
Dr. Barry Tillman (22:12):
We do. It’s going to be on August 8th this year, and it’ll be an early morning start again and last half a day. We’re actually meeting here next week to begin planning our speakers and all the stops. But yeah, we’re looking forward to that day again. It’s always a good day. It’s usually one of the hottest days of the year, so you can come enjoy that and a few gnats.
Mike Howell (22:30):
I well remember the gnats, but I do want to let all our listeners know if you happen to be in that area on August the 8th, that field day is definitely worth going to. Always one of the best field days that I have been to. Dr. Tillman, where do you see the farm going in the next 50 years? You’ve talked about the history. What’s the future look like?
Dr. Barry Tillman (22:48):
Well, that’s a really good question. I hope that on the peanut breeding side, we’re continuing to do what we’ve always done. There’s no doubt that breeding is a continuous exercise. We can’t just stop and then restart it. It’s a process. It takes 10 years sometimes that we make a cross until we release a cultivar. So you can’t just stop that and restart it at a moment’s notice. It’s a continuous effort, and as I mentioned before, it’s been going on since the late ’20s here in Florida or early ’20s. I think the first cultivar was released in 1943, but the breeding efforts began in the ’20s in Gainesville, so that effort continues. I’m just one in a long line of breeders who’ve been running this program, so in the next 50 years, I hope that that continues. I believe if we’re successful, we’ll help the industry continue to maintain sustainability and profitability.
(23:31):
There’s a lot of the bahiagrass pastures around this southeast, right? That’s one of our biggest grasses, but it’s a pretty poor forage from a nutrient standpoint. So I really feel like that if we can develop some techniques and varieties through our breeding program and agronomists that would allow legumes to be integrated into that system, growing sort of as a companion crop with the bahiagrass, it would improve the nitrogen-protein balance in that system and improve weight gain. I think that’s an achievement that’s sort of relevant to us. It’s been shown by our agronomists here to work. It’s just a matter of how do we get it implemented out there in the real world.
(24:05):
The other part of it on the animal side is genetic. The ability to utilize the feed efficiency facility to improve the weight gain potential of cows is really something that’s exciting from a genetic standpoint as well as the feeding material that they’re using. We’re working with our animal scientist colleagues here, looking at feeding peanut hulls and some of the things that they may bring to the table for animals, especially when it comes to methane production. So even though we’re working in quite disparate areas, there’s areas of overlap that we think are unique because of our location here and the fact that we have animal scientists and agronomists on the same site together.
Mike Howell (24:39):
Well, Dr. Tillman, we appreciate you taking a few minutes to visit with us this morning and tell us about the research farm there at Mariana. Listeners, thanks for tuning in this week and as always, if you need any more information on anything we’ve talked about today, you can visit our website. That’s nutrien-eKonomics.com. Until next time, this has been Mike Howell with The Dirt.
