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[00:00:00] Mike Howell: 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.
Listeners, welcome back to the Dirt. Glad you’re tuning in. We’ve got a little bit different episode for you today. Before we get into the different part of this episode, we’re gonna welcome back Dr. Brian Hopkins from BYU, Dr. Hopkins. Welcome back to the Dirt. Thank you, Dr. Hopkins. If you will, before we get started, remind our listeners a little bit about what you do there at BYU.
[00:00:58] Dr. Bryan Hopkins: I’m a professor here at BYU. I do teaching and research. I have kind of a unique background, which is reflected in this interview today. My first degree was in turfgrass science, and I have spent some of my career focused on turfgrass and sports turf, especially golf. But I also have an agricultural background.
And in terms of my current research, I do both. I have about 50% of my research is in. Turf grass and about 50% is in agriculture. I tend to focus on shallow rooted crops and potatoes are shallow rooted and so is turf grass typically. Anyway, I kind of got an odd background that not too many in the world do, but that’s me, odd.
[00:01:36] Mike Howell: Dr. Hopkins, we had you on earlier in the year and we talked a lot about potato production. How is the potato crop going this year? Is it harvest time yet? Just getting started
[00:01:46] Dr. Bryan Hopkins: in most of the main places, of course, you have to supply potatoes all the time, especially for the french fry market, like McDonald’s is the behemoth.
They require just a constant fresh supply of potatoes, and one of the things that we do to make good money on potatoes is if you can keep them in storage for a long time. And so our goal in my family’s operation is to try to keep ’em all the way through July. That’s about the limit of what we can do reliably, but we can really have a pretty high sell value on the crop if we can do that.
But then you start kind of running out about July. So we do have some folks who have already started harvesting the early crop based on contracts. And some of the fields I’m working in got sprayed here recently to prepare ’em for harvest. You typically kill the vines three weeks before you harvest. So that’s starting up, but it’s still a little early.
Most of the crop will start coming out about the second week of September.
[00:02:41] Mike Howell: Well, Dr. Hopkins, what we wanted to talk about today is you kind of alluded to it was turfgrass management and thought it would be good to do that. Last weekend was the start of college football. Always an exciting time. We love to go dove hunting in the morning, get that kicked off, and then sit around and watch college football in the afternoon.
I know there was a lot of exciting games that happened. Saturday. Not going to get into the results of those games. I know some people are excited and some people are a little disappointed after this opening weekend. Wanted to talk a little bit about the field that everybody plays on. Some people play on a natural surface, some people play on an artificial surface, but the goal there is to make that surface as productive as possible.
Keep it safe for the athletes. But today we wanted to focus on a natural surface and what it takes to make that. The best possible playing surface for these athletes to play on. And Dr. Hopkins, I understand that you have quite a bit to do with the football field there at BYU, and our listeners may be thinking, well, that’s basically just an acre of grass, what possibly could be challenging about growing an acre of grass.
So let’s talk a little bit about what goes on there. We know that you have a natural surface there as opposed to an artificial surface. So let’s start with that. Why did BYU choose to go with a natural surface versus an artificial surface?
[00:03:51] Dr. Bryan Hopkins: That’s a complicated topic that we could spend at least an hour talking about, but I’ll try to give a brief synopsis and I’ll just show my bias right outta the gate that I am not a fan of artificial surfaces environmentally.
They’re a problem. I can list all the reasons why, but they’re just not good. Maybe more importantly, they’re not as safe for athletes. There’s a lot of data out there. Everything from higher injury rates. We’ve measured those personally on our surface compared to when we play in artificial surfaces.
There’s some really good scientific studies. It’s not always super clear, but to me, the preponderance of data shows they’re not safe, they’re hot, they’re miserable. I used to play football. Coached football. And I can tell you it was miserable when you had to coach and get three a days going on on those artificial surfaces.
And we’ve measured temperatures as hot as 180 degrees. You do a search on the internet and you’ll find situations where cleats were melting. That’s not a safe situation. That’s more likely to not just have lower body injuries, but to have heat exhaustion and it’s just not good. And typically athletes, unless you’re a kid in high school, who’s got stars in your eyes seeing these?
Really beautiful artificial surfaces and they are, they’re gorgeous. That’s one of the appeals. But if you look at the professional athletes, the guys who live this, they almost to everyone want to play on natural grasp Surveys in the NFL, for example, are greater than 95% of those athletes prefer natural grasp.
There’s some interesting conversation, you know, like when Odell Beckham got. Injured. He’s blaming it on the grass. And I can point to several situations where athletes’ careers were ended because of injuries on the surface anyway. They wanna play on natural grass. It’s just where we ought to be playing football.
It’s hard though. Uh, so what you mentioned is, isn’t it just growing grass on an acre? No, it’s not. It’s complicated and because it’s complicated, more and more high schools are switching over ’cause it’s. Easier. In some ways, they get talked into the idea that it’s cheaper, which it’s not. It’s not cheaper.
You give the same budget and I will give you a beautiful grass field. I can do that, and those of us who are experts in it can, but it’s not a simple situation for a lot of reasons. Traffic is one of ’em, but also mowing short. Typically coaches want the grass mowed short, and for some of the grasses like Kentucky Bluegrass.
Doesn’t like to be mowed short. We tend to get some challenges. We get compaction, surfaces get hard and we can’t have that. You know, that’s unsafe. Like if you’re playing on a natural grass field and it’s as hard as the parking lot, well that’s not safe. So we can’t do that either. We need safe surfaces.
[00:06:25] Mike Howell: Dr. Hopkins, I really wish I had you close to Poplarville, Mississippi. I need somebody else to help me out with this. Our local football coach came to me, it’s been five or six years ago, and they were having trouble growing the grass on the field, and my son had told him that I did a little bit with fertilizer and he wanted to know if I could help him out.
And we did some work out there that summer and we had him grass growing. Really nice, beautiful field, but. The next year, I went back, I said, I’ve got some more fertilizer. He said, I don’t need it. We’re putting in artificial turf, and I threw a fit. He said the reason they were doing it was because they had nine teams that were playing on that field between football and soccer.
They just could not keep it going with that much traffic on the field. And I kinda understand that. You can practice somewhere else and play and keep the field in good shape as well. There’s a way to do it. But after they put the artificial surface down, I got to notice and the kids would come over off the field to get water, and instead of drinking the water, they were pouring the water on their feet.
And I got to asking my son, and it’s exactly like you said, it was so hot. They had to cool their feet off. They were having blisters on their feet because it was so hot out there. And I’d never thought about that, but it’s a real problem. There are situations where you
[00:07:30] Dr. Bryan Hopkins: just don’t have any choice. Like here at BYU, for example, we have.
Intermural fields that just have constant play. And it’s really tough to have natural grass if you don’t have some opportunities to keep the surface healthy and give it a little bit of a rest. And obviously, indoor facilities, now there’s some exceptions to that, but most indoor facilities, there’s no choice but to have artificial notable exceptions.
Uh, Arizona Cardinals and Las Vegas Raiders, for example, they grow their grass outside and then they. Pull it in for the professional teams. Dallas Cowboys can switch out between artificial and natural in less than one day. And then you’ve got some hybrid stadiums, like the Madrid Stadium is like this technological marvel where they’re growing grass and still playing inside.
So anyway, there’s some exceptions, but there are cases where you have to have artificial and to be fair. It’s getting better. When I was a player, Idaho State University’s field was concrete. I mean, it was a carpet on top of concrete. It was terrible. I hated it. It was painful to play on it. And I’ve played on Boise State’s field, the blue smurf turf, they call it.
[00:08:39] Mike Howell: I was gonna bring that up at the end, tell you we needed to do something about the blue field, but since you brought it up, why did they select a blue turf up there?
[00:08:46] Dr. Bryan Hopkins: I really don’t know. That’s a good question. I don’t know the answer to that. We always kind of made fun of ’em, but yeah, it certainly has brought them some notoriety.
Everybody knows about it, so I mean, that’s the big advantage of artificial is I don’t have to paint it all the time. Right. And if you’re growing natural grass painting, that’s a big part of your budget and it’s a pain in the rear, especially if it’s raining in Mississippi. That’s hard to do and a little easier.
In Utah, we don’t get as much rain. Anyway. What I’m saying though is that the artificial fields, the technology is definitely better than it used to be. It is getting safer and there’s some technology there that’s improving it, but I’m still not a fan.
[00:09:22] Mike Howell: Well, Dr. Hopkins, let’s spend a few minutes and talk about some of the challenges associated with growing this turf and some of the things people may not even think about.
You just mentioned one, and that’s the paint. Now I’ve painted a few football fields in my day. Now we just painted the stripes on ’em. We did not paint the end zone like y’all will have to be doing there at BYU. Grass has to have sunlight, and when you’re painting the stripes on those fields and painting the end zones, different colors, that’s going to interfere with the sunlight, getting to that and interfere with the grass growing.
Talk about how you deal with the paint and keeping the grass growing.
[00:09:53] Dr. Bryan Hopkins: Yeah, and that’s a bit of science and an art. Our field manager, Dustin Pixton, he’s great. He’s got tons of experience in professional soccer and football and anyway, he’s really good at his craft and we have other. Folks on be with campus that are really good at the paint part of it.
Robotic painters are really helping, especially high schools, you don’t have to have as much sophistication as maybe you used to. So there’s really some great technologies that are helping with paint. But yeah, you’re right. You put a paint on and you are inhibiting photosynthesis. These paints, they’re specialty paints.
They’re biological paints. We don’t just use the paint from Walmart. We have to buy specialty paints and apply it, and they are less likely to cause damage, but they do inhibit growth. Heat can be an issue. For example, we get requests sometimes from athletics and whoever, and they wanna paint the end zone black or dark blue.
For the first game at the end of August, you’re gonna have to replace that end zone because those. Dark colors are gonna absorb the heat and it will kill most of that grass. If it’s white paint, it’s not gonna absorb as much heat and you’re more likely to be okay. However, these fields are getting painted six times.
Like in a college football, it’s six times and every other week-ish. And if you do that by the end of the season, the grass is definitely thinner in those areas that are consistently getting painted. There’s some things we can do to try to overcome that a little bit. Try to continually putting on new seed, try to reduce the growth.
We put in some growth regulators, which is also nice because then you don’t have to paint as often. That’s especially good for a high school. If I can kind of slow that growth down. I don’t have to paint every single game maybe, or certainly don’t have to paint for practice. So those are all things that have to be managed.
The fact is it does get a little thin if you watch games, which I do. I have to watch every game twice. ’cause I first watch how the grasp performs and then the next time I watch it, I watch and see how the players did. But I watch these kinds of things ’cause I do a lot of consulting in the NFL and for colleges, et cetera.
And so I’m always looking, but you’ll notice the divots still come up. There’ll be more, by the end of the season, you’ll have more divots like where logos are painted, for example. ’cause that grass is struggling in those areas.
[00:12:03] Mike Howell: Well, Dr. Hopkins, we talked about sunlight and photosynthesis. One thing we may not think about is shadows.
You know, different stadiums have different structures and it may be taller on one side and shorter on the other side. Or now everybody has a jumbotron that’s gonna be putting shadows out on the field, so part of that acre of grass is going to get sunlight a lot more intense than another part of that field.
How do you manage the areas that have more direct sunlight versus the areas that have more shade during the day?
[00:12:29] Dr. Bryan Hopkins: Yeah, that’s a huge thing. And again, some stadiums are worse than others. This time of year, you’ve got pretty good coverage. Not too many shadows, but yeah, by November, certainly December and even January in the pros, you’ve got some pretty big shadows.
Like in our stadium for example, we got a big jumbo tron in the south end, and. We get some pretty good shading. So by the last game of the year, that ground is frozen solid at that end of the field, which is not safe either. That’s a concern. I’m a proponent in high-end college fields and professionals, and on those kinds of fields, one thing you can do is put in a heating system.
So like Real Salt Lake, for example, soccer up in salt. Green Bay Packers, Chicago Bears have these underground heating systems. We even have one in our baseball field, which is artificial, but it doesn’t really keep the grass from going into dormancy. That’s still gonna happen, but if we can keep the ground soft.
Then it’s gonna be a safer surface. And so I think that’s one thing that you can do. And that’s not cheap. High schools aren’t gonna be able to do that. It’s a problem. But high schools can be built to where you don’t have too much of a shading problem when they build the field. They need to be thinking about that.
But like you said, in a big. Stadium. You’re gonna have shade, you’re gonna have to deal with that. Trying to keep the grass alive and not going into dormancy. We can cover the field. There’s some cool technologies for that. Putting on growth blankets, that’s gonna help. Sometimes we can blow air, warm air in there that can help.
There’s lights. In fact, there’s some really cool new research on wavelengths and lighting. FIFA is coming to the United States, north America. As part of that, they have sunk a lot of money into research and there’s some really cool stuff coming out in terms of being better at being able to have portable lights.
And so a lot of professional teams now have that. They have portable lights that they kind of move around in the stadium. Just trying to keep that grass growing a little healthier and giving it a little more sunlight during those times of year. So a number of things that could be done. Everything from low budget, just planning your stadium right to high budget with these various technologies.
[00:14:33] Mike Howell: Dr. Hopkins, another thing we have to worry about, and you kind of alluded to it as compaction zones. You talked about the end zone with the paint and getting compacted on the end zone in the shadows, but there’s a lot of traffic areas, especially on a football field, between those hash marks get a lot more traffic than it does on the outside of those hash marks.
What can you do to manage the compaction in these high traffic areas?
[00:14:54] Dr. Bryan Hopkins: The main tool that we have is aeration my lawn at my house. I have never aerated it, and I’m the turf guy at BYU. I just, I don’t have enough traffic to worry about it. It doesn’t really get compacted, but areas that get a lot of foot traffic or vehicle traffic, they need to be aerated.
It’s important to have different types and depths of aeration. So for example, we might go through and use like a six inch. Core that you know, by the time you get across the field, those spikes have actually reduced down to four inches. ’cause that sand is abrasive and it actually wears ’em out. Get a single use out of ’em.
So that’s not cheap, especially if it’s a sand field to do aeration. But you really need to, do I need to do the whole field? Maybe not. Maybe just the center part, especially if I’m a high school. Just pick the places we can measure that. We have devices that are not that expensive to measure how compacted a field is.
The NFL requires that we have certain types of tests that we have to do before a game, and if it’s too hard, they will not play. For example, a few years ago there was a game in Mexico City that got canceled. ’cause it just was too hard. So those kinds of things can happen and need to be dealt with, with aeration.
I also mentioned different types. So we’ll have deep tying, like go down nine inches. We have aeration that can kind of twist back and forth to sort of fracture the soil. In some cases you have air that you can push into the soil to actually pop it up. So there’s different types of aeration, but that needs to be done.
Usually we do that in cooperation with. Top dressing with sand that has a number of purposes helps keeps the thatch down to a reasonable level. We want some thatch that helps. It’s kinda like a blanket, a little softer surface, but excess thatch is not good. And so top dressing and aerating can help reduce the thatch, helps keep the surface even.
So we typically on athletic fields are aerating and top dressing. Now on the high end fields, we want to use a sophisticated technology like we have at Lavell Edwards Stadium here at BYU. And it is technology that was first developed in golf. When golf started getting popular after World War ii, if you look at golfers during a rainstorm, they’re standing in the clubhouse.
Just wait for it. As soon as it stops raining, they wanna go out and golf. Well, all that traffic on those little greens and tee boxes, it’s too much. You know, so you’d get these muddy messes. So some really, uh, smart soil scientists back in the day used some sophisticated technology to figure out how to build perch water table systems with soils that won’t compact.
So in golf that like PGA. High-end golf courses, they’re gonna have what we call A-U-S-G-A Spec Golf Green. In sports world, we have, it’s pretty similar, but it’s A STM Spec Sports surfaces. These are sand based fields. It’s not just any sand. It has to be very specific sand, and it’s sand sitting on top of gravel.
The gravel and the sand have to be specific sizes and shapes in order for it to work. What will happen is that you create a perched water table, so the water contrary to maybe what might seem obvious, like, oh, well the water’s just gonna pour through that. Actually no. If you build it right, water will perch up in the sand, and so the grass is happy.
It’s got some water in the root zone. It doesn’t. Ever gets so high as long as I build at the right height, which is textbook is about 12 inches. And that varies depending on the type of sand. So if you have this 12 inch thing, the bottom six inches or so is just water down there in the sand, plenty for the roots, right on the surface though it’s dry enough that it’s good to play on.
And then the other thing that’s cool is that if you get the right size and shape of sand. It doesn’t compact. So I’m the architect for the field of BYU and that when we first built it, I had these daily construction meetings and the manager, he said, yeah, we put on an extra inch of sand and now we’re gonna compact it with those huge rollers.
Right? Not some little tiny thing like construction level rollers. And I said, it’s not gonna compact guys. And they kinda looked at me like, yeah, right. Anyway, they went out there and did the back. So they ended up having to take an inch off in order to meet specs, which was not cheap. But yeah, it doesn’t compact even with 350 pounders running out there.
So on those fields, I don’t have to aerate as often. We still do aerate and eventually after years of building up organic matter and a little bit of silt and clay, blown in coming in on the water, whatever, over time, they start to compact a little bit. But that’s on the high end fields. That’s what we are typically doing.
High schools. You can’t afford that. You wouldn’t want to. It’s too expensive and technical to try to grow grass on these fields, but for those guys, you just need to be religious about aeration and top dressing. It needs to be part of what you do. Some soils are better than others. I got a call from a local high school to do some consulting for them, and they wanted to put in a sand base field, and I went down there and looked at their field and I’m like, man, this is a beautiful soil.
This soil has got nice aeration and structure and takes in water. I talked him out of it. You know, there were a couple places on the field that were a mess that we had to fix. So it kind of depends on your budget and what you do. But typically aeration is the answer.
[00:19:48] Mike Howell: Dr. Hopkins, speaking of drainage and some of these high schools that can’t afford to do this sophisticated drainage, one thing they like to do is keep those fields level, and that’s probably the worst thing you can do.
If you could put a crown in that field and let that water roll off to the sides, it seems to help drain those fields a lot better. I’ve been on some fields that were. Pretty much cut to grade and they seemed to hold water a lot worse than the ones that had a crown in the middle of them.
[00:20:12] Dr. Bryan Hopkins: Yeah, that’s a really great point you make, and I teach that.
I teach an urban soil and water class here at BYU, and it’s one of the things I focus on is the first thing you ought to be thinking about is surface drainage. So for football fields, we would typically wanna put a crown, like you say. The field at Auburn, for example. I don’t know if it still is, but it used to be the biggest crowd.
It was like 36 inches. I think the middle of the field was 36 inches higher than the outside edge. You would watch games and first half the opposing quarterbacks would typically overthrow ’cause it was such a. Difference. And believe it or not, there’s no standard for that. They can kind of do what they want, but yeah, usually like a 12 to 18 inch crown is going to give you good surface drainage, get a big barn burner, and you gotta have somewhere for it to go.
Obviously with soccer, that’s tough. You really can’t do that. You need a flat field because if you got an 18 inch crown, the coach on the other side of the field can’t even see the player’s feet or even the ball. So you can’t do that in those fields. You want them flat, but you tilt them, we want at least a 1% or 1.5% slope and they, it’ll drain those soccer fields.
You want ’em to drain side to side, not end-to-end. If you try to do end-to-end, you create some problems. But I can drain 40 yards, 50 yards is sideways. That’s not a problem. So even Lavelle Edwards, even though we have that sophisticated drain system with our perch, I failed to, actually, I failed to say that on that Persch water table system.
If we get a big rain, like a few years ago, we had a game with Texas and it just dumped several inches of rain in just a few minutes. And what happens on that perch water table? Same thing on a golf grain, is that if it fills up, it actually starts to drain and it’ll just drop the water down into that gravel.
You get enough hydraulic head on it. Even though we have that system at Lavelle Edwards Stadium, we still have a crown. Just extra precaution, but you don’t have to. If I have that perch water table system. I can be totally flat and I’m fine. Like at real Salt Lake professional soccer team up in Salt Lake City, they have a Persch water table system like I’ve been talking about, and their field is completely flat with no slope at all.
So you can do it, but in general, high schools definitely wanna have a crown on the football fields or a slope on the soccer.
[00:22:22] Mike Howell: Dr. Hopkins. Another issue with water is irrigation, and this is one of the things that I see a lot of, especially high school coaches. They need a lot of help with this. They’ll have practice in the morning and then they’ll get out there and turn the water on 11 o’clock in the morning and let it run till three o’clock when they get ready to have a second practice.
And that’s probably the absolute worst thing they can do. Can talk about irrigation when they need to be watering these turf surfaces and how much irrigation they need to be applying and timing, that kind of stuff.
[00:22:50] Dr. Bryan Hopkins: It really depends on the soil. If I’m on a sand, I can do that and get away with it. But if I’ve got any amount of clay, normal soil loam, soils, you don’t want ’em having traffic on ’em when they’re wet, that’s gonna create compaction and gonna destroy your surface, and you don’t wanna be too dry either.
Right. I always use the analogy of. For the beach, right? If I’m at the beach, I’m gonna build my sand castle, not out there in the water where the sand is completely wet, there’s no strength, it just falls apart. But if you go out too far away from the beach up into the below sand where there’s no water that has no strength, it doesn’t hold together.
But in between those two places, water is actually kind of acting like a glue. And so that’s where I want to be during practice and games is I wanna have a modest amount of water. You don’t want ’em too dry, not too wet, and that’s hard to give an exact formula for timing because I’m down there in Mississippi with a heavy clay soil.
That’s gonna be probably a different answer than if I am up here in Utah on a sandy loam soil. Also, the grass type matters too. The two main. Grasses for sports turf in the south is Bermuda grass and preferably hybrid Bermuda grass. And in the north it’s Kentucky Blue Grass. Those are almost exclusively.
We do get some fields with tall fescue and a few others, but they make up the vast majority. So if I’m down in Mississippi and I’ve got hybrid Bermuda grass and clay soils. I can get away without watering that for several days. That hybrid Bermuda, it roots deeply. As long as you’re fertilizing it right and treating it right, it should have nice deep roots down in that soil.
And I can possibly even get away with just waiting until after the game on Friday night and then water up on Saturday. I’ve had consulting situations where that works just fine. Most of the fields, I can’t do that. I’m gonna have to water during the week, so I might need to wait if I’m in two days and I’ve just gotta water.
Then I wait till after that second practice and try to give as much time as I can between turning on the water and the next practice the next morning. It takes about 24 hours for the gravitational water to escape most of these fields. But if you can wait and give it a day, a full day before you get any traffic, that’s the best scenario.
And there’s a whole bunch of other things to factor in in terms of good water management, but that’s super important. Water’s kind of keying, and if you’re not doing that right, then you’ve got other problems.
[00:25:09] Mike Howell: Dr. Hopkins, you talked about fertility. What do we need to think about in terms of fertility?
When we’re talking about turf grass, we want it to stay lush and green, but we don’t necessarily want it to grow like we would a forage crop out in a pasture or a potato crop or a cotton crop. We wanna keep it manageable, and that was one of the problems we had on the football field here at our local high school.
We put the fertilizer on it, and we grew a lot of grass. They had to mow it at least once a day. Sometimes it could have been mowed twice a day, but. They did not appreciate having to mow it that often.
[00:25:39] Dr. Bryan Hopkins: When I teach this, I sort of think about things in two categories, with nitrogen being the most important category and it’s managed differently than most of the rest.
I need nitrogen there, especially on sports fields. It’s really important for recovery. Bermudagrass and bluegrass both will kind of repair themselves, but they gotta have the nutrients they need, and so you need the right amount of nitrogen. Excess nitrogen herz rooting, and I don’t want that. I need good root growth.
I think that’s really imperative to make sure that I’m not putting on excess nitrogen, and that’s easy to do. And frankly, most of my sports field managers are putting on more nitrogen than they should. The golf guys, I dunno why they got it figured out better. Typically with good high-end golf courses, they seem to dial that in.
But I have a hard time convincing some sports field managers to back off on their nitrogen. You don’t want too little either. Again, you gotta have it. I tell people sort of the minimum, like if I’m a high school low budget, I’m gonna put on about three pounds of nitrogen. For my Kentucky Bluegrass annually, and that’s gonna get spread out.
I’m gonna put on about one pound in the spring with about 50% slow release, like ESN. You could use ESN or other polymer code like duration, polymer code urea, or other slow release nitrogens. I tell people at least 50% slow release about one pound total nitrogen in the spring.
[00:27:05] Mike Howell: Dr. Hopkins, let me stop you.
We’ve got a lot of row crop people here. You’re talking one pound per,
[00:27:09] Dr. Bryan Hopkins: oh, I’m sorry. I switched over to my turf grass folks, one pound of nitrogen per thousand square feet. In the urban world, that’s what we talk. We don’t talk acres, but yeah, thank you. Glad you stop me there. Anyway, about a pound in the spring, and then you need about two pounds in the fall.
Again, if I’m in a low budget situation. I can get away with that. I can put on one pound 50 Soul release, quick release in the spring. And then about right now, end of August, 1st of September, I’m gonna put on two pounds on my Kentucky Bluegrass. Again, 50 50. And that’s gonna get me through. That’s a pretty inexpensive program to do that.
Now, if I’m in a little higher end program, I’m gonna bump that up to maybe four or five pounds. I’m probably gonna put on an application early summer. I might put on as much as three pounds in the fall, especially if it’s sandy. If it’s really sandy, more likely to leach that out. So three to five pounds.
Now for Bermuda grass, for my Southern guys, we tell people about one pound of nitrogen per thousand square feet. Per month of active growth. So if I have 12 months of active growth, then that’s up to 12 pounds. Now, I personally wouldn’t do that. Um, by using the slow release, I can cut that back and I do usually, I’m usually half that.
So if I’m eight months of active growth, frankly I’m still probably at that four or five pound annual application rate for nitrogen. I think that’s a good formula, and I do tissue testing to watch it. Especially on a high end, like BYU, we’re gonna tissue test. There’s no reason not to do that. And that way I know if I’m a little high, I can dial it back and it’s gonna cut down on my mowing and my clippings and my painting.
It’s gonna save a lot of things and better roots. I mean, there’s just a lot of reasons. So I actually spend a lot of my time consulting, dialing in nitrogen and getting it down to, okay, what’s my minimum? And still have a nice green grass. Now switching over to the other nutrients. Sulfur’s a little bit like that.
So I kind of lump my sulfur in with my nitrogen. I usually just put on ammonium sulfate as part of what I do, and then my sulfur’s usually taken care of. I could talk about that for a month, but that’s a simple solution right there. But phosphorus, potassium, possibly micronutrients, although grass is really good at just scavenging those.
We don’t see that too often, but I really get on people about soil testing. You need to soil test. Same as we talked about with potatoes. I’m not just gonna go out there and, and that’s what most people in the urban environment do. If you’re a farmer and you did that, you’d be broke, you’d be outta business.
And there’s a reason for that. It’s not good to have too much of nutrients. So what I see commonly in the sports turf world, I come in, take a soil sample, the phosphorus, potassium levels are sky high, even sometimes toxic. Like it’s possible. But that’s what we do. We just find some formula. We go down to homeowners, same thing, right?
Going down to. Lowe’s, home Depot, whatever, and you buy something that’s got all the nutrients and you just go out there and put it on you never soil test. And after a few years of that, you’ve just got yourself into a problem. And I’m dealing with one this week where they were like, we do not know our grass is sick.
We cannot figure it out. They had phosphorus levels that were sky high. So soil test, if you need it, you need it. I mean, we definitely wanna have enough. Phosphorus is really important, especially on sports fields to help that grass recover when it’s damaged, but excess not a good thing. The soil test isn’t as critical for nitrogen.
Nitrogen doesn’t hang around like phosphorus and potassium does, and so I sort of have my recipe for nitrogen and sulfur and then. My p and k and the micronutrients. I really just point people to soil testing and I’m happy if anybody wants to reach out to me. I do a lot of free consulting too, just, you know, if somebody’s just got a soil test, I’m happy to say, Hey, this is what I do, and I’m happy to help people with that.
[00:30:45] Mike Howell: Dr. Hopkins, well, we’re on that subject about the p and k. Just because you go down to your local store and get a 25 pound bag of fertilizer, that doesn’t mean you have to put the entire bag out on your lawn this year. If you don’t need 25 pounds, you can seal that back up and use the rest of it next year.
I get that question quite a bit. Just because you have to buy 25 pounds doesn’t mean you have to apply 25 pounds. I want everybody to keep that in mind. Dr. Hopkins, we’ve talked a lot about growing the grass and getting a good quality turf out there, but we also know we have to mow that grass, and that’s quite a challenge on these athletic fields.
We want to have that grass just right. Talk a little bit about what we need to pay attention to when we start mowing the grass and how tall we need to keep the grass and things like that.
[00:31:28] Dr. Bryan Hopkins: The battle there is. Coaches and players are just almost universally convinced that you have to have low mowing height for speed and whatever, and that’s just not true.
Scientifically, several studies have been done and doesn’t affect athlete speed at all. Now, there are some other reasons maybe why we would wanna mow low. For one thing, if I’m playing a night game in the fall, I’m more likely to get the water in the canopy and it gets a little more moist. And so having a short mode grass is a little bit beneficial there.
Golf obviously affects ball roll. We mow golf greens down at a tent or an eighth of an inch, and it affects how fast and how smooth and straight that ball will roll. Same thing in soccer. So we’re typically kind of stuck with low mowing. The problem is, is the bluegrass and the tall fescue, the other cool season grasses, they’re typically upright type growth and they wanna be mowed two, two and a half inches, maybe even three inches is where sort of their happy place is.
And that’s higher than we typically wanna have. If. Sports field. If I can get people to mow at an inch and a half, I’m happy because I feel like my grass is happy. But most of the time that’s too tall for their liking. And so inch and a quarter, or even an inch, sometimes three quarters of an inch, if you’ve got a big budget, your professional football team or soccer, and you can afford to replace your grass fairly often.
Go ahead and mow at three quarters of an inch. Your bluegrass, if you’re at high school, you should not be doing that because you can’t afford probably to be replacing that grass very often. And so mowing at three quarters of an inch, you’re just creating an unhealthy situation for that bluegrass.
Bermuda grass is warm, season grass. It has more prostrate growth. It can be mowed really short. It’s used on golf greens, you know, it’s extremely short and be fine, but it can also tolerate taller mowing and. Inch, inch and a half is no problem. So you’ve gotta kind of know your grass, but like three quarters of an inch on Bermuda, that’s great.
That’s not a problem at all. The other concept here for both of them though, is the lower you mow the more often you have to mow. If you take off more than about one third of the chute. Anyone mowing that harms the grass and it can actually slow down root growth for a couple of weeks if you do that.
Sometimes we get people, especially high schools, making the big mistake of they just mow it once a week and they mow it too short. Well, you can’t do that. If you’re only gonna mow once a week for bluegrass, you probably ought to be mowing it. Two inches, maybe one and a half at the very lowest. If it’s Bermuda, you can mow once a week at an inch, and that’s not a problem.
Maybe even three quarters of an inch, but you start going below those levels, then you’re gonna have to mow more often. If you’re a golf green, you’re mowing pretty much every day. If you roll it and do some other things right, you can get away with every other day. Most sports fields, they’re mowing every day, every other day.
Typically. One of the challenges with sports fields though, is paint. And as soon as we start laying the paint down, then we’re not mowing anymore. And so that’s an issue. So I have to think about mowing versus painting. I can’t not have the field painted, and especially if something goes wrong, I gotta have a little bit of buffer time.
And we’re usually starting like three days out to paint fields and then you are not gonna mow, and then you need to mow as soon as you can. Like for us. If we have a game, let’s say you have a game Saturday night. Well, the field manager, he’s mowing right after the game because it hasn’t been mowed for like three or four days.
And we know this rule of if we let it go too long, it’s a problem. So that’s really a tricky part of that, especially for high schools that have low budgets. I would just suggest if you can’t afford to mow. Twice a week, then you shouldn’t be mowing low. There’s studies that show it’s not gonna affect your player’s speed.
Anyway, I hope that answers your question.
[00:35:09] Mike Howell: Yep. Back when I was playing, our coach would let the grass get really tall when we were playing certain teams and mow it really short when we were playing other teams trying to speed ’em up and slow ’em down. I didn’t think it worked back then, so I’m glad to hear you say that.
Dr. Hopkins, last question I’ve got for you. This time of year, we’ve got our summer grasses, and they’re growing great. They’re looking really well here in a few weeks, in some areas, couple of months in others. We’re gonna get this first frost and we’re gonna start losing these summer grasses and they’re gonna go dormant.
We still want to keep this good green grass for our playing surfaces. Do you have any tricks? How can we keep a green field in the later months? Well, some of the things we’ve talked about help.
[00:35:45] Dr. Bryan Hopkins: Good agronomics. It starts there, right? Let’s make sure that we’re fertilizing, we’re watering, and we’re mowing.
Right? That alone is going to give you a little bit of an extension in terms of dormancy. Other than that, it’s tough because if I have a big budget, then there’s some things I can do. I mentioned earlier the growth tarps that can help. For example, I have a friend, Tony Leonard is the manager of Philadelphia Eagles.
He has effectively used those growth tarps, even though he’s growing Bermuda grass, which is a warm season, not really suited for Philly, but yet there’s some real advantages of Bermuda grass, and he went with it and he has been able to use growth tarps to keep that looking good. Even late season games with the pros and looks really good.
I’m, I’m always so impressed at what he’s done there. The other option, again, on Bermuda grass is to over seed. That’s not too terribly. Expensive or difficult, like if you really want to have green grass. It’s pretty commonly done, very commonly done in the pros and the college about right now actually, or maybe in the next couple of three weeks.
You can go ahead and moat really short, even possibly phrase mowing if you have time. Depending on what sport it is. If it’s football, you can’t do that, but mow down, detach it really well. Put some perennial ryegrass seed is usually what we use. Some folks use Kentucky Bluegrass. But you can oversee that and it’ll pop up.
So like for example, Arizona Cardinals, they do that every year, right? So in January you’re looking at the green part of that grass is actually the perennial rye. The, the Bermuda is still underneath, it’s still alive, but it’s dormant. It’s knitting everything together. It’s giving you the good surface.
Like you can’t have a peral ryegrass sports field. It’s a terrible sports grass, but as an over seed on top of Bermuda, it gives you the color, a lot of dissatisfaction. It’s hard to get it out so it doesn’t look bad the next year. That’s a little bit of an art and a science, but that’s another option that you can do.
If you have the bluegrass, though bluegrass is pretty tolerant to cool conditions and it’s surprisingly avoids dormancy, even getting some hard freezes in there if you’re in the north, that’s really an option. Now, one of the main focuses of my research in recent years is using hybrid bermudagrass in northern areas.
We have it growing here in Provo. We don’t have it on our football field. We don’t have any of our sports fields, but we’re looking at it anyway. That’s a bit of a challenge. We’re facing significant drought issues and Bermuda uses less water. It’s one of the reasons why we’re looking at it. Plus, to me, quite honest, Bermuda versus bluegrass.
Bermuda’s a better sports field surface. It’s gonna knit together, it’s gonna play better, gonna have less slippage, and so kinda like it for those reasons. But yeah. Anyway.
[00:38:26] Mike Howell: Dr. Hopkins, we really appreciate you taking time to go through all of this with us. It’s a little longer episode than we’re usually turning out, but I think we got some great information out of this and hope it’s something that some people can use.
Do you have any closing comments or anything that we may have left out that you wanna leave our listeners with before we sign off?
[00:38:42] Dr. Bryan Hopkins: Maybe just say, I think it’s important that we have, there’s a lot of folks anti grass and they want to switch over to artificial or have rock lawns and. I, I don’t think so.
I think there are ways to be able to have our grass. Yeah. Maybe at my home I ought to cut back my grass and I have, I don’t have a ton of grass, but I think it’s important that we have golf courses and that we have sports fields and we have places for kids to play on playgrounds and. I want plants.
Plants are a good thing for our planet. They’re good for all kinds. I got a list of like three dozen scientifically proven reasons why it’s important to have plants in our lives. Everything from generating oxygen to sequestering carbon out of the atmosphere. But anyway, it is important to learn how to do it right and.
Going back to what we started with, with artificial. If you’re switching to artificial because you just can’t get the grass to survive and look well, well, then you just need to ask some questions. There are some resources out there that we can point you to to help you get a healthy natural grass surface. It’s possible.
[00:39:42] Mike Howell: Dr. Hopkins. Thanks a lot, listeners. We hope you enjoyed this episode as much as we enjoyed bringing it to you, Dr. Hopkins, if you need some more controlled release fertilizer for that school up north to help get that bluegrass turned green, we can probably help you out with that. Listeners, if you’ll hang around for just a couple of moments, we’ll be right back with segment two.
Farming Isn’t farming without questions, and now there’s a place to go for answers. At economics, an entire team of agronomists is waiting and ready to help for free. No question is too big or too small. Visit Nutrien-ekonomics.com and submit your question with the ask an agronomist feature.
Listeners, welcome back for segment two. As you know, segment two is where we ask one of our agronomists a question of the week to help us do that today, we’ve got Alan Blaylock back in the studio with us. Alan, welcome back to the dirt. Thanks, Mike. It’s always good to be here. We always have some great conversations.
Alan, this week’s question has to do with sulfur fertilization. You know, everywhere we go, more and more people are talking about the need for sulfur fertility. Is there a difference between using sulfate sources compared to an elemental source of sulfur?
[00:40:51] Alan Blaylock: That’s a great question, Mike, because there are real significant differences in those sources.
Now, there may be cost differences. Elemental sulfur is often less expensive, so growers may want to go that route. Ammonium sulfate, for example, the sulfate form is. Oftentimes a little bit more expensive than the elemental, but the key difference is the sulfate form is the form that the plant is going to take up.
Whatever form of sulfur we apply has to be in that form or converted to that form before the plant can use it. The elemental sulfur is not immediately plant available. It has to be converted in the soil by special sulfur oxidizing bacteria that convert elemental sulfur to the sulfate form. And this.
Takes time. We want to be aware of the conditions and the fertilizer properties that influence that rate of oxidation. Soil properties that influence that are temperature, moisture, warmer soils will oxidize faster. Remember. This is a biological process, so warmer conditions tend to hasten that process.
Cold soils are going to be very slow, so we wanna consider those soil conditions and we need moisture present. Those bacteria can be active. They need similar moisture conditions to what a growing crop need. The soil near field capacity with nice warm temperatures is going to have the fastest oxidation rates.
Now, the other key factor is the fertilizer properties itself. Now typically what we’re looking for are a couple of things. The particle size of that elemental sulfur, once the fertilizer granule breaks apart. So the fertilizer granule with elemental sulfur is really a bunch of really tiny particles pressed together or bound together in some way.
Some forms use a bentonite clay to bind those sulfur particles together. Others, it may be fused into a matrix of a soluble fertilizer like our MAP plus MST product. It has. Elemental sulfur incorporated into that mono ammonium phosphate granule. What is the particle size of that? Elemental sulfur that’s in the basic fertilizer.
Smaller particles oxidize much faster there. There’s a lot more surface area for those bacteria to work on. If we look at that particle size, these micronized sulfur oxidized faster than some of the other sulfur that have larger particles. Now that doesn’t mean that those others don’t have value, but we need to recognize the rate.
Which they’re oxidizing. If they’re oxidizing too slowly, they may not become available within the growing season that we’re targeting. Now. They may have long-term value into the next growing season, or maybe over the next couple of growing seasons, those larger particles can take some time. And then lastly, how well does that fertilizer granule disperse the materials with clay binders they take in water and that clay swells.
And so. Breaks that granule apart and allows those fine elemental sulfur particles to disperse. If they’re kind of bound in the soil, perhaps in a banded application, they may not disperse very well. On the surface, they’ll disperse much better. And then the others that are in a soluble matrix like fused into a mono ammonium phosphate, or some other soluble fertilizer, like there’s materials that have elemental sulfur in urea or maybe in potash.
So some of these things are soluble. Fertilizer materials, they dissolve. And the elemental sulfur particles then can disperse in the soil. So particle size, smaller particles oxidize faster. More dispersion creates faster oxidation and warmer, moist soil conditions create faster oxidation. So these are some of the key factors the growers need to evaluate and take that into account when they’re deciding what to purchase.
Do I need the sulfur right now? Early in the season, maybe a crop that takes up sulfur very early, like canola in our Canadian prairies. It needs sulfur early. Those soils are cool. I’m going to need something that’s going to oxidize quickly, or I want to use the sulfate form, or maybe some combination. If I’m in a warm environment, like down where you are, I have warm temperatures and I’m growing a crop like corn or cotton.
It’s gonna have sulfur uptake a bit later into the growing period. Well, I may be able to use one of those elemental forms and get very good performance. And so we look at the crop and the environment and the fertilizer itself, and all these things go together to create different combinations of what the grower may want to choose.
[00:44:58] Mike Howell: Alan, great answer on that, and I think you hit three of the four Rs that we’re always talking about in that answer there. The only one you didn’t talk about was the rate, and we’ll save the rate for another question. Listeners, we appreciate you tuning in this week. As always, if you have any more questions about anything we’ve talked about today, you can always visit our website.
That’s Nutrien-ekonomics.com. Until next time, this has been Mike Howell with the Dirt. Hey guys, if you like what you heard today, do us a favor and share this podcast with someone else. It could be your neighbor, your friend, your crop advisor, or whoever you think would enjoy it. Your support helps since your future episodes, so please like, subscribe, share, and rate the show wherever you’re listening from.
