The science of World Cup grass

Summary

---

Science Quickly – The Science of World Cup Grass

Host: Rachel Feltman (Scientific American)
Guest: Dr. John Trey Rogers III (Professor, Turfgrass Management, Michigan State University)
Date: June 10, 2026

---

Episode Overview

This episode explores the fascinating, high-stakes work behind the grass used at the FIFA World Cup 2026. Host Rachel Feltman interviews Dr. John Trey Rogers III, one of the leading turf experts responsible for orchestrating the transformation of North American stadiums—many of which usually feature artificial turf—into world-class natural grass pitches. The discussion covers grass species selection, groundbreaking growing and transportation methods, the science of hybrid “reinforced” turfs, and the unique logistical and scientific challenges faced in creating world-class playing surfaces for the world's most-watched sporting event.

---

Key Discussion Points & Insights

1. The Challenge: Converting Stadiums for FIFA’s Strict Grass Standards

• FIFA’s natural grass requirement: FIFA has never hosted Men’s World Cup games on artificial turf and mandates real grass for top-tier matches ([03:07]).
  • Quote (Rogers): “FIFA… has not played a men's World cup game on anything but natural grass and since its inception. So they're not going to change that for 2026.” ([03:07])
• Many North American stadiums, especially in the U.S., use artificial turf for their flexibility and multi-use; 7 out of 11 U.S. host stadiums fit this category ([03:39]).
• Five host stadiums are domes, ill-suited for growing real grass, presenting further complications ([03:39]).

2. Picking the Right Grass Species

• Cool vs. warm season choices:
  • Cool season: Kentucky bluegrass & perennial ryegrass blends
  • Warm season: Bermuda grass ([04:54], [05:32])
  • Selection is tailored to stadium climate and environmental conditions.
• Unique case – dome stadiums: Even in hot cities like Dallas, Houston, Atlanta, domes will use cool-season grass because their indoor climate (kept at 72–73°F, with grow lights) favors it ([06:08]).
  • Quote (Rogers): “This blows people's minds... Houston and Atlanta and Dallas where it could be 105 degrees outside and the cool season grass would burn up in the heat. But it's going to be inside where it's 72 degrees...” ([06:08])
• Mexico City exception: Despite being southern, its high altitude is cooler, supporting perennial ryegrass & Kentucky bluegrass ([07:10]).
  • Quote (Rogers): “Because of your altitude, you're 8,000ft above sea level. You don't get as warm as you think...” ([07:10])

3. The Complexity of Grass Species and No “Perfect” Turf

• Only about 20 species are globally relevant for stadium or lawn use ([07:53]).
• Every species has its pros and cons—there’s no “perfect” option ([08:09]).
  • Quote (Rogers): “There's no such thing as the perfect turf grass. No one size fits all. Every grass has an Achilles heel.” ([08:09])

4. Turf Reinforcement Technology

• Hybrid approach: Most fields will use natural grass reinforced with synthetic fibers ([08:54]).
  • Two systems:
    • Stitched: Synthetic fibers sewn into the pitch after sod installation ([09:12]).
    • Carpet: Synthetic carpet with open backing, pre-planted with grass at a sod farm, then installed ([09:22]).
• Cities could choose their preferred system; three opted for the carpet, others for stitching ([09:24]).

5. Logistics of Growth, Harvest, and Transport

• Cool-season grass for domes is grown in cooler climates (e.g., Denver area) and trucked, sometimes over 1,000 miles, under refrigeration ([09:44]).
• Los Angeles’s sod came from central Washington ([09:44]).
• Innovation: Growing sod on large sheets of plastic (“sod on plastic”) ensures robust root systems and minimizes shock during transplantation ([10:12]):
  • Quote (Rogers): “We establish the grass and the roots grow down to the plastic and then... laterally. This makes for very strong sod... when you transplant it, you’re not putting it in any physiological shock.” ([11:14])
• All stadium sod is uniquely prepared and timed for installation roughly a week or two before play starts; Houston was the last to receive its sod ([12:02]).

6. Playing Experience, Tradition, and Performance Demands

• Players are used to and demand natural grass—especially elite athletes from European leagues ([13:19]).
  • Quote (Rogers): “You get the best performance by being able to play on something that you're used to.” ([13:19])
• Even subtle differences in bounce, speed, or “stickiness” of the pitch are perceptible to top athletes ([14:05]):
  • Quote (Rogers): “They know when something doesn't bounce as well. They know when something isn't as fast, when the ball... sticks.” ([14:11])

7. The Scientist’s Perspective

• The immense scale and complexity meant intense travel, on-site visits, and collaboration ([14:42]).
• Personal impact: The process has been both “intense” and “fun,” and a career highlight for Dr. Rogers ([14:42]).
• Turf professionals always notice—and critique—sports field conditions, even outside of work ([15:46]).
  • Quote: “My wife does not like to take walks around the neighborhood with me because I am critiquing. But that's just my nature.” ([15:57])

---

Memorable Quotes & Notable Moments

• “FIFA... has not played a men's World cup game on anything but natural grass and since its inception. So they're not going to change that for 2026.” — John Trey Rogers III ([03:07])
• “This blows people's minds... Houston and Atlanta and Dallas where it could be 105 degrees outside and the cool season grass would burn up in the heat. But it's... 72 degrees [inside].” — John Trey Rogers III ([06:08])
• “No such thing as the perfect turf grass. No one size fits all. Every grass has an Achilles heel.” — John Trey Rogers III ([08:09])
• “We establish the grass and the roots grow down to the plastic... this makes for very strong sod... when you transplant it, you're not putting it in any physiological shock.” — John Trey Rogers III ([11:14])
• “You get the best performance by being able to play on something that you're used to.” — John Trey Rogers III ([13:19])
• “They know when something doesn't bounce as well... isn't as fast, when the ball... sticks.” — John Trey Rogers III ([14:11])
• “My wife does not like to take walks around the neighborhood with me because I am critiquing.” — John Trey Rogers III ([15:57])

---

Timestamps for Important Segments

• 01:13 — Introduction to the significance of turf for World Cup
• 03:07 — FIFA’s natural grass mandate
• 04:54 — Grass species selection
• 06:08 — Dome stadium adaptations
• 07:53 — Number of relevant grass species
• 08:54 — Turf reinforcement technology explained
• 09:44 — Innovative sod growing and transport logistics
• 12:02 — Precise installation timing before games
• 13:19 — Why FIFA insists on natural grass: performance and tradition
• 14:42 — Personal reflections on the work
• 15:46 — Turf scientist “occupational hazard:” always critiquing lawns

---

Conclusion

The preparation of grass for the World Cup is a science just as dramatic and consequential as the matches themselves. Rogers and colleagues have navigated a labyrinth of climate, logistics, and technical hurdles—adapting decades of turfgrass science in service of the ultimate sporting spectacle. The result: pitches that, if done perfectly, “nobody particularly notices”—the silent foundation for world-class soccer.

---

Transcript

[Accenture Sponsor]

This episode is brought to you by Accenture. When your advertising operations fall out of sync, everything else follows. Spotify and Accenture are working together to reinvent the rhythm of ad sales, using automation, analytics and smarter workflows to simplify campaign delivery and access better data across the business. The result? Less time spent on operations, more time connecting brands with the moments and fandoms that matter most. Learn [e-mail] Spotify this episode is brought

[Facebook Sponsor]

to you by Facebook. So you were scrolling on Marketplace and there it was, the bike you'd been searching for. You sent a message and it turned out the seller was super chatty, kind of funny, and an avid cyclist. The next thing you know, you're in a cycling crew. Well, a community cycling group. The thing about Facebook, you might find more than what you're looking for. From a browse to a bike ride, you can this summer find more on Facebook.

[Rachel Feltman]

For scientific american science quickly, I'm rachel feltman. It's no secret that most of us could do with going out and touching some grass. But for some scientists, touching grass is much more than a metaphor for logging off. And watching grass grow is anything but

[Interviewer]

a waste of time.

[Rachel Feltman]

In fact, for people like today's guest, grass, sorry, turf is more even than a mere occupation. It's a calling. While this passion for low profile plants might strike strikes some as strange, their work is about to have a huge impact on the most watched sporting event in the world. For around five years, turf experts from the University of Tennessee, Knoxville and Michigan State University have been tasked with solving the surprisingly complex puzzle of preparing North American stadiums for FIFA World cup gameplay. They've spent that time researching bespoke oak blade blends, testing cutting edge growing methods, and gaming out the logistics of cross country turf shipment. With the World cup now just a day away, they're hoping for the ultimate sign of success. Grass that looks like grass and that nobody particularly notices one way or the other. Our guest is John Trey Rogers iii, a professor in turf grass management at Michigan State University. We spoke to him late last month about the challenges he and his colleagues faced when they were tasked with pitch the best turf options to North American stadiums. Thanks so much for coming on to chat with us.

[John Trey Rogers III]

Absolutely.

[Interviewer]

A lot of people hear turf and they think Astroturf. But FIFA demands real grass, at least partially. So why don't we start with just what exactly are we talking about when we talk about the turf being used at these games?

[John Trey Rogers III]

This is real grass. This is natural grass. My discipline calls this turf grass. When we think about Artificial, we go ahead and put the word artificial turf in there or synthetic turf. So all of those will work. And certainly FIFA to my knowledge, has not played a men's World cup game on anything but natural grass and since its inception. So they're not going to change that for 2026.

[Interviewer]

Yeah. And is that different from what most of these stadiums would usually be using?

[John Sorokin]

So, yes. Here's the rub of this whole thing,

[John Trey Rogers III]

right, is that FIFA identified 16 cities and in three countries, three in Mexico, two in Canada and the rest in the United States. And of the 11 in the United States, seven of those 11 multi use stadiums whose grass or whose surface playing surface typically is artificial. So this was not going to work for FIFA. And so the job that they gave Michigan State University and the University of Tennessee was help us solve the idea of getting a natural turf field in for the 2026 World Cup Games into these stadiums that were not built for natural grass. Oh, and by the way, five of the 16 stadiums will be in domes which certainly weren't built for natural grass, with one small exception in Houston. And so come up with solutions. Michigan State University. Come up with solutions. University of Tennessee. And we want evidence based research. And that's what we've been doing since basically 2020.

[Interviewer]

Wow. So let's, you know, at the beginning, you know, how did you select what the best species of grass would be?

[John Trey Rogers III]

Well, there's some basic thoughts here. Number one is that the best cool season grass that we can use is a mixture of Kentucky bluegrass and perennial rye grass. Now this is outside in many people's home lawns. This is outside in many stadiums today. But it's just not going to be managed as intensively as it's going to be managed for this event. The other grass is a warm season grass called Bermuda grass. Now, there actually was a couple of other choices in warm season grasses besides Bermuda grass, but we wanted to keep this very simple. So the Bermuda grass was our choice. And this is the one that's used

[John Sorokin]

mostly around the world.

[John Trey Rogers III]

So now we're down to basically two grasses. It's either a cool season grass, bluegrass, rye grass, or it's a warm season grass, Bermuda grass. Now it's basically fit. Which grass is going to fit into which stadium may seem complicated, but at the same time, the five dome stadiums, interestingly, even though we bring in supplemental light, we've got grow lights to grow this grass. They're not strong enough to support what a warm season grass would need. So all the cool season grasses will be in dome stages this is significant and this blows people's minds.

[John Sorokin]

Why?

[John Trey Rogers III]

Because we're talking about Houston and Atlanta and Dallas where It could be 105 degrees outside and the cool season grass would burn up in the heat. But it's not going to be in the heat. It going to be inside where it's 72 degrees or 73 degrees in a temperature that it's going to be able to survive. We're just going to need to put lights on that.

[John Sorokin]

And all of those provisions have been made. They turn around to warm season grasses.

[John Trey Rogers III]

And there's two Mexico stadiums are going to have warm season grass. Monterey, Guadalajara, and then we'll also have warm season grasses in San Francisco, Kansas City and New York, New Jersey. This probably makes sense. They're very hot, humid places. And also Miami, which makes even total sense.

[John Sorokin]

One that won't make a lot of

[John Trey Rogers III]

sense to a lot of people is that in Mexico City, which is the furthest south, we are going to have a cool season grass, perennial ryegrass and Kentucky bluegrass. Because our research showed, and we went

[John Sorokin]

down and showed as Decker Stadium and

[John Trey Rogers III]

all the people that work there, this was the best grass for you because of your altitude, you're 8,000ft above sea level. You don't get as warm as you think for using a warm season grass. So we would like to have you consider changing grasses. Do a series of experiments.

[John Sorokin]

They did and they agreed.

[John Trey Rogers III]

And you know, this is another of the accomplishments of Michigan State University and the University of Tennessee staff, graduate students and professors.

[Interviewer]

As somebody who is realizing that I know basically nothing about grass, about how many species are there that sort of fit into the group of what a layperson would just recognize as grass that you might have on a lawn or in a stadium.

[John Trey Rogers III]

I think there's around 20 grasses around the world that you could say people who use. And I would say there's around 20 that if you were in my beginning turf grass class that I would teach you to identify.

[John Sorokin]

And that's kind of an overwhelming number

[John Trey Rogers III]

for a lot of people.

[Interviewer]

Sure.

[John Trey Rogers III]

And so the first thing that's learned in turf grass 101 is there's no such thing as the perfect turf grass. No one size fits all. Every grass has an Achilles heel. Nothing's perfect. And because if it was, I always remind the students, why would you be here? We wouldn't have anything to talk about. We would just plant the grass and walk away. So grass has to fit a situation, like you said, you don't think about it. And then when you start thinking about it, you realize it's pretty complicated and it's kept a guy like me enthralled for 40 years.

[Interviewer]

So for the FIFA grass, I know that it, you know, it goes through a lot of wear and tear during the World cup games. So I've heard that it's reinforced. What does that mean and how does it affect the growing process?

[John Trey Rogers III]

Really doesn't affect the growing process. The reinforcement is a kind of a synthetic, like an artificial at this point. And it's in one of two forms. You can either reinforce it using fibers that get kind of stitched into the ground, literally with seven foot wide sewing

[John Sorokin]

machines on one by one inch centers,

[John Trey Rogers III]

or it can be prepared as a carpet, a synthetic carpet with very open backing.

[John Sorokin]

And then that is prepared at a

[John Trey Rogers III]

sod farm and brought in. So we have both, because each city got to kind of choose what they wanted to. Three stadiums will use the carpet, the others will use the stitch. And the stitch normally is done after the sod is installed.

[Interviewer]

And what are some of the unique challenges of growth and transport that you guys had to think about?

[John Trey Rogers III]

So let's just take the cool season grasses in the dome stadiums. When you think about where Dallas and Houston and Atlanta are located down in the south southeast, and we need to grow the grass in a northern climate, all those grasses had to come from just outside of Denver, Colorado. So that meant they had to be transported well over a thousand miles in some cases. Same type of thing as the stadium. Los Angeles, their side came from Central Washington. So this obviously means that you have to take great care and everything has to travel in refrigerated trucks so that it doesn't heat up. And then something we haven't discussed yet is the preparation of the sod. The preparation of the sod is something that's very unique to the United States and the United States alone at this point. And that is called growing sod on plastic. Big sheets of plastic. And the best way for me to describe it to you and to your listeners is that if you think about a flower or a plant that's in a pot and you were to lift that whole thing out, it would all come out and the roots would be stopping right at the edge of the pot. And that's what Sodom plastic is. So we establish the grass and the roots grow down to the plastic and then they start growing laterally. And this makes for very strong sod that, you know, is very strong as far as moving around.

[John Sorokin]

But the most important thing is when

[John Trey Rogers III]

you transplant it, you're not putting it in any physiological shock. And anybody that's ever dealt with a

[John Sorokin]

home lawn or dealt with any, any

[John Trey Rogers III]

type of grass and has had sod

[John Sorokin]

brought in, they know the very first thing is, boy, you don't water that solid for a week, it's going to burn up and die.

[John Trey Rogers III]

And the reason is because the plant has to reestablish totally re establish a new root system.

[John Sorokin]

Well, not with Sodom plastic, not in the way that we are delivering sod

[John Trey Rogers III]

from the farms to the stadiums.

[John Sorokin]

It's all being done as sod on plastic.

[John Trey Rogers III]

A couple of exceptions.

[John Sorokin]

But at the same time, this has been one of the big keys to success.

[Interviewer]

Yeah. And what's the timeline like today? It's May 26th. You know, how long before the games is the sod going into the stadiums?

[John Trey Rogers III]

Well, the sod is in every stadium except one.

[John Sorokin]

Right now.

[John Trey Rogers III]

There's one left to go and that's Houston. And it is actually going in the last week of May, so right about now.

[John Sorokin]

And there's others that have been in a little bit longer than that as they have been doing some test matches, but not dome stadiums, places like Boston

[John Trey Rogers III]

and Seattle that wanted to do some test matches. Because, you know, you have to remember is that if you've been a stadium that hasn't had natural grass in it, and then all of a sudden we build you a natural grass field, you.

[John Sorokin]

You kind of got to learn your animal, you kind of got to learn

[John Trey Rogers III]

how the grass is going to react. Are there little idiosyncrasies that you'd like to know about?

[John Sorokin]

And you have a lot of stadiums

[John Trey Rogers III]

that this is where they do grow natural grass. Kansas City, Philadelphia, San Francisco, Miami.

[John Sorokin]

Well, that's not something that they had

[John Trey Rogers III]

to get necessarily used to because they're always grass. So it's been very complicated. It's a very complex situation.

[Interviewer]

So I guess a natural question that arises for me is I'm not going to ask you to say whether this is worth it, but what is it that makes FIFA feel so strongly about using real grass and how much does it actually impact play?

[John Trey Rogers III]

The best leagues in Europe are always played on natural grass. And so what you have majority of the best players. Even if you're from Australia, you might be playing in one of these European leagues, because that's really some of the strongest soccer leagues. But they're played on natural grass. And so that's what they are very used to. And you have to realize that you get the best performance by being able to play on something that you're used to. And that's really been driven into us. Even some of these, the reinforcement they have, the reinforcements in Europe, and so

[John Sorokin]

they're used to that as well.

[John Trey Rogers III]

And so FIFA wants to try to get the best performance out of everyone.

[John Sorokin]

And so the natural grass is the way. And one of the things that is

[John Trey Rogers III]

a great challenge for us is trying to make these grasses all play the same.

[John Sorokin]

And again, these are the best in the world. So they know when something doesn't bounce as well.

[John Trey Rogers III]

They know when something isn't as fast, when the ball, quote, unquote, sticks.

[John Sorokin]

And you say, is that really something

[John Trey Rogers III]

that they can tell?

[John Sorokin]

Yes, it is.

[John Trey Rogers III]

It is no different than a professional golfer being able to tell you that a green is reacting different. So you're the best in the world and you get paid millions of dollars to perform. Obviously, it's not my world as far as performing for soccer.

[John Sorokin]

Preparing a soccer pitch has world, obviously.

[Rachel Feltman]

So, yeah.

[Interviewer]

Has it been fun, the challenge, over these last few years?

[John Trey Rogers III]

Fun. Fun's a good word. Intense is a good word. I spent a lot of time in an airplane looking at sod farms, because all these sod farms, they're located all through North America. Sad to see them all many, many times.

[John Sorokin]

I did, and so did my colleague John Sorokin, because this was something that FIFA really counted on us to do as the agronomist to bring us in.

[John Trey Rogers III]

So it's been intense, but it's been

[John Sorokin]

very enjoyable because I've had three wonderful graduate students, all of which have gotten one gotten a Master's, one's achieved her

[John Trey Rogers III]

PhD, and another one's about to achieve his PhD.

[John Sorokin]

And I'm very confident that this is going to be a springboard for them to go on and do great things long after I'm gone. I'm almost 67, so I'm at the end of my career. But at the same time, this has been a fun, fun project.

[John Trey Rogers III]

Kind of a repeat for me.

[Interviewer]

Yeah. Do you ever watch sporting events and find yourself kind of critiquing the turf or seeing some performance issues that maybe could have been solved with some more thoughtful grass preparation?

[John Trey Rogers III]

I would say it's much easier for me to think the other way. I don't see very many stadiums or very many fields where I'm not critiquing.

[John Sorokin]

And my wife does not like to

[John Trey Rogers III]

take walks around the neighborhood with me because I am critiquing. But that's just my nature.

[John Sorokin]

I don't speak unless asked.

[Interviewer]

Occupational hazard.

[John Sorokin]

I'll say it out loud.

[John Trey Rogers III]

That's right.

[Interviewer]

Well, thank you so much for coming on to chat with us. This has been great and I will definitely be more appreciative of the turf from now on when I'm watching World cup games.

[John Trey Rogers III]

You're very welcome, Rachel.

[Rachel Feltman]

That's all for today's episode. We'll be back on Friday to talk about how movies like Disclosure Day tackle the notion of alien language and what these constructed languages can teach us about real linguistics. Science Quickly is produced by me, Rachel Feltman, along with Fonda Mwangi, Sushmita Pathak and Jeff d'. Alvisio. This episode was edited by Alex Suguira, Marielle Issa and Erin Shattuck. Fact Check our show. Our theme music was composed by Dominic Smith. Subscribe to Scientific American for more up to date and in depth science news. And don't forget to check out our Summer Reading Challenge for a chance to win some awesome prizes. You'll find a link to that in our show. Notes for Scientific American, this is Rachel Feltman.

[Interviewer]

See you next time.