All About Artificial Turf

Podcast Transcript

In 1965, the world’s first fully enclosed sports facility, the Houston Astrodome, was opened to the public.

The Astrodome itself was a marvel of engineering, but because it was enclosed, the grass that was initially planted soon died.

It was replaced with artificial grass, which was basically a synthetic carpet that looked like grass but played and behaved totally differently.

Today, the next generations of that artificial grass can be found in stadiums all over the world.

Learn more about artificial turf, how it was created and improved over time on this episode of Everything Everywhere Daily.

You’ve probably heard the adage that necessity is the mother of invention.

This is definitely true with the development of artificial turf. It was a case of the need for the product coinciding with the development of the product, which resulted in an explosion in the adoption of the product.

There are several threads in the story of the creation and adoption of artificial turf.

The first of these starts in the state of Texas.

In the late 1950s, the city of Houston was awarded a Major League Baseball franchise, the Houston Colt .45s, which was later renamed the Astros.

The problem was that Houston’s hot, humid climate and frequent rainstorms made outdoor baseball uncomfortable for players and fans. Judge Roy Hofheinz, a former Houston mayor and visionary businessman, spearheaded the project, imagining a futuristic indoor stadium where weather conditions wouldn’t interfere with gameplay.

Construction began in 1962, and by the time it opened in 1965, the Astrodome was an engineering marvel. The stadium featured a massive dome spanning 642 feet or 195 meters in diameter, supported by a steel framework.

When the Astrodome opened, the original plan was to use natural grass on the playing field. To allow sunlight to reach the grass inside the domed stadium, the roof was designed with clear acrylic panels.

However, players quickly complained about glare from the sun reflecting off the panels, making it difficult to track fly balls. To solve this issue, officials painted a large portion of the panels white, significantly reducing the glare but also blocking natural sunlight from reaching the field.

As a result, the original grass, Tifway 419 Bermuda grass, began to wither and die due to the lack of sunlight. Groundskeepers attempted various solutions, including installing grow lights, but none were successful in keeping the grass healthy. With a deteriorating field and no viable alternative for maintaining real grass, the Astros had to look for a synthetic replacement.

The next thread of this story begins in the 1950s with a company named Chemstrand.

The Chemstrand, which was a subsidiary of the Monsanto corporation, began developing synthetic fibers for various applications, including surfaces that could mimic grass.

This eventually developed into a product released in 1965 known as “ChemGrass.”

ChemGrass consisted of short synthetic fibers made from nylon, woven into a backing material. This first-generation product was essentially a carpet with no infill, resulting in a very firm surface that bore little resemblance to natural grass beyond its green color.

It was first installed as a test in 1964 at the Moses Brown School in Providence, Rhode Island.

The introduction of ChemGrass coincided almost perfectly with Houston looking for an artificial grass alternative. It was installed for the 1966 season, but the problem was that there wasn’t very much of it at the start of the season.

They only installed it in the infield and foul territory. The outfield was just painted dirt until the midseason when they finally had enough for the whole field.

Given its association with the Astrodome, the product was rebranded as AstroTurf, a name that became synonymous with artificial turf.

Despite the fact that it was installed in the Astrodome because it was an indoor facility, it soon began being installed in outdoor stadiums.

Artificial turf rapidly gained popularity throughout the 1970s, particularly in North American professional sports.

By 1974, over half of the NFL teams were playing on artificial surfaces

Major League Baseball saw widespread adoption, with many new multi-purpose stadiums installing synthetic turf.

The 1976 Summer Olympics in Montreal featured artificial turf in several venues, and it started gaining attention in international soccer.

Why exactly would teams playing in outdoor stadiums want to install artificial turf when they can easily grow natural grass?

Artificial turf offers several advantages, including low maintenance, durability, and cost-effectiveness over time. Unlike natural grass, it does not require mowing, watering, or fertilizing, making it ideal for areas with heavy foot traffic, such as sports fields and public spaces. It also remains green year-round and can be used in various weather conditions without becoming muddy or patchy.

Natural turf also has a habit of getting torn up, especially in American football when extreme forces from 300 pound players running with cleats would tear up huge divots.

However, astroturf also had huge drawbacks.

High initial installation costs can be a barrier, and while it lasts for many years, it eventually needs replacement. Another major issue is heat retention, as artificial turf absorbs sunlight and can become significantly hotter than natural grass, making it uncomfortable for players and spectators.

However, the biggest drawback was injuries.

Turf toe is a sprain of the ligaments surrounding the big toe joint, commonly occurring when the toe is forcefully bent upward (hyperextended). It often happens on artificial turf surfaces, where the harder, less forgiving ground increases the likelihood of excessive toe bending, especially for athletes making quick cuts or sudden stops.

While mild cases can be treated with rest, ice, compression, and elevation, more severe cases may require immobilization, physical therapy, or even surgery in extreme instances.

These drawbacks eventually led to the development of the next generation of artificial turf.

Second Generation artificial turf, introduced in the 1970s and 1980s, marked a significant improvement over its predecessor. This iteration featured longer and softer fibers, typically made from polypropylene, which provided a more comfortable playing surface. A key innovation was the introduction of sand infill, which helped to stabilize the fibers and improve the overall durability of the turf.

This generation of artificial turf was designed to better withstand high-traffic areas and offered improved shock absorption, reducing the risk of injuries compared to the first generation. The longer fibers and sand infill also allowed for better ball roll and bounce, making it more suitable for a wider range of sports.

Despite these advancements, Second Generation turf still faced criticism for its heat retention and abrasiveness.

Third Generation artificial turf, introduced in the 1990s, represented a significant leap forward in synthetic playing surface technology. This iteration featured even longer fibers, typically measuring between 40-65mm in length, which closely mimicked the appearance and feel of natural grass.

A key innovation was the use of a mixed infill system, combining sand with rubber granules derived from recycled tires. This infill mixture provided superior shock absorption, enhanced player comfort, and improved overall field performance.

The longer fibers allowed for better water drainage, reducing the risk of flooding and improving playability in wet conditions. Additionally, third-generation turf incorporated more advanced backing materials and improved manufacturing techniques, resulting in increased durability and longevity. These enhancements made third-generation artificial turf suitable for a wider range of sports, including soccer and rugby, and significantly reduced the risk of injuries compared to earlier generations.

Despite the advances in artificial turf, many athletes still didn’t like it. Running on sand and recycled tires wasn’t the same as running on natural grass and soil.

So what is the state of the art in turf today?

I should preface this by saying that there are several companies out there that sell turf systems at various price points for all levels of athletics, from ultra high end systems for the NFL or top European football leagues, down to high school fields.

Many of these are completely artificial systems that closely, but not perfectly, replicate the feel of natural grass.

However, today’s most advanced turf systems are not artificial, but rather a hybrid of natural grass and artificial turf.

I want to close by describing how these hybrid systems work and how they integrate the best features of natural grass and turf.

As you will soon see, it is a far cry from the nylon carpet that was introduced in Houston in 1966.

Here is a short list of some of the teams which use hybrid turf fields: Manchester United, Manchester City, Liverpool, Arsenal, Barcelona, Paris Saint-Germain, AFC Ajax, the Philadelphia Eagles…..and of course the Green Bay Packers. It has also been used in multiple national stadiums around the world and has been used in several World Cups.

There are several different hybrid systems that are on the market today, including the Grassmaster by Desso Sports from the Netherlands and the SIS Grass system from EuroSportsTurf in Germany.

These hybrid turf systems reinforce natural grass with synthetic fibers to enhance durability, stability, and playing conditions. The system involves stitching artificial fibers into the natural grass surface, creating a stronger, more resilient playing field that maintains the natural feel of grass while improving wear resistance.

To install a hybrid system, a specialized machine injects over 20 million polypropylene fibers vertically into the soil, at a depth of approximately 7 inches and spaced about ¾ inch apart. The natural grass is then grown around and intertwined with these synthetic fibers, forming a reinforced root system.

The fibers make up only 5% of the surface, ensuring that natural grass remains the primary playing surface, but they provide additional support by anchoring the grass roots, preventing excessive turf damage, and reducing the formation of bare patches.

One of the key advantages of a hybrid system is that it improves field stability and drainage, making it ideal for stadiums with high foot traffic and varying weather conditions. The synthetic fibers help distribute player weight more evenly, reducing divots and wear patterns, especially in areas of high activity, such as the center of the field and goal areas.

Additionally, the system enhances grass recovery time, meaning that the field stays in better condition for longer periods, even with frequent use.

Because hybrid systems still rely on natural grass, regular maintenance such as watering, mowing, aeration, and fertilization is required. However, the reinforcement provided by the synthetic fibers allows the field to withstand intense play and adverse weather conditions far better than traditional grass surfaces.

There is more to the field than just the grass and the artificial strands that hold everything together.

Most of this system, especially if they are outdoors, will be built on a large layer of sand for drainage. An American Football field, which is similar in size to a regulation soccer pitch, will have over 42,000 gallons or 159,000 liters of water fall on it with just one inch of rain.

Some systems like the Grassmaster system can support drainage of up to 10 inches of rainfall per hour. 10 inches in an hour would approach a world’s record for rainfall.

In cold weather climates, like Lambeau Field, freezing is a huge potential problem. During the Ice Bowl, the famous 1967 championship game that took place in Green Bay, temperatures dropped to ?15 °F or ?26 °C at game time.

The nickname Frozen Tundra was coined during this game, and the reason the field was frozen was because the electrical heating system buried beneath the field wasn’t working.

Today, they have a very elaborate steam system that keeps the field warm and avoids freezing.

Because they might have games well into January, they have artificial grow lights that they put over the field in the winter months so the grass stays healthy.

They will also put a tarp over the field and blow hot air underneath to keep it warm.

One of the newest technologies that is being installed on fields is below-ground sensors. When distributed across a field, they can provide temperature and moisture information across the playing surface.

Artificial turf has become more common around the world, whether it is fully artificial or part of a hybrid turf system.

The simple grass field has actually become a high tech, highly engineered system.

So the next time you watch a sporting match that is played on something that looks like grass, realize that it might actually be an extremely sophisticated replica of the real thing.

The Executive Producer of Everything Everywhere Daily is Charles Daniel. The Associate Producers are Austin Oetken and Cameron Kieffer.

Today’s review comes from listener The Lawyer, yes that one over on Apple Podcasts in Canada. They write.

Fabulous podcast

Just joined the completionist club here!

I know this would be a nightmare to organize, but a friend I got addicted to the show mentioned in passing that it would be great for enthusiasts in a specific area (for him: modern industrial machinery) to be able to filter the episodes on your website by category so they could at least somewhat tailor to their niche interests and then binge on all those episodes.

From myself, all I have to say is that I’ve learnt a lot and expanded my knowledge significantly thanks to this show, which has also sent me down numerous rabbit holes which, for better or for worse, have ended up swallowing entire afternoons.

Keep up the great work!

Thanks, Lawyer! I don’t disagree with your idea for grouping episodes together by topic, but it is one of those things that I’ll do “someday” when I can find the help. It’s always hard to get around to when you have a new episode every day.

Remember, if you leave a review or send me a boostagram, you too, can have it read on the show.