The Best of Both Worlds

Know When to Rely on Synthetic or Natural Turf

There doesn't have to be a choice between installing and maintaining natural or synthetic turf fields. Each has its pros and cons, and an ideal situation is to have both—a synthetic field can take more traffic with little effect, while natural turf is favored by many athletes for its springiness and by purists for its aesthetics.

Many times, what matters the most is simple: What is the best way to use budgets—both installation and maintenance? How do you decide between higher installation expense and lower maintenance cost, as with synthetic turf, and the low entry cost but higher operation and maintenance expense of real grass?

 

Find the Best Value for You

 

Brian Daviscourt, a horticulture graduate student and athletics maintenance intern at Oregon State University, recently delivered his master's thesis on a study he's done for the past three years. Focused on five synthetic and five grass fields, Daviscourt used budgetary and maintenance information as well as usage data to determine which type of field was a better value.

"If someone was going to plan to install a field or was thinking about upping their maintenance program to deal with certain conditions, it would give a little bit more information into that. So, by looking at the number of hours that a field is being used, you can kind of figure out if your money is truly being used efficiently, to come up with a unit price essentially," Daviscourt said.

"If a maintenance program is putting a whole bunch of money into a synthetic field and they're barely ever using it, the cost they're paying to provide an hour of use to somebody is much higher than someone who would be using a natural grass field for the same amount of traffic. My goal was to estimate how much each maintenance department was spending to provide an hour of use to a single person."

Though the study took three years, Daviscourt was able to look at information covering a 20-year period to include installation and resurfacing of synthetic fields. The analysis included field installation, the years of maintenance between installation and the first resurfacing, and a similar number of years after resurfacing.

For synthetic turf fields this meant the life-cycle analysis included the projected discounted costs for 16 to 20 years, as most synthetic infill systems have a warranty that expires after eight years, but many facilities attempt to extend the life of their fields to 10 years. For maintenance and replacement scenarios with different planning lives—16 years versus 20 years—the net present value (NPV) of future dollars was converted to annual equivalents by amortizing the NPV into an annual equivalent payment using the discount rate.

Hours of use and participant numbers for the fields were collected from athletic directors, coaches, online schedules and player rosters. By multiplying the hours of use by the number of participants, the number of individual hours of use could be calculated. Then by dividing the individual hours of use for a single year into the annual equivalent, the cost of providing an individual with an hour of use was determined.

Daviscourt concluded that synthetic fields had a mean cost of $3.25 per player use hour, and natural grass fields had a mean of $3.48 per player use hour. It cost less to provide an hour of use on synthetic infill because most of the synthetic fields in this study had almost three times the hours of use as the natural grass fields.

Maintenance, Traffic & Water

Daviscourt admits this empirical take on the grass versus synthetic debate is not the only basis for making a decision. He lists three major criteria: money, traffic requirement, and access to water.

He said research has continued to support the idea that natural grass fields are less expensive to maintain in the long run. However, his case studies suggest that once you take hours of use into consideration, synthetic fields end up costing less to provide an hour of use.

"In talking with maintenance employees across the state, a theme became clear: Most of the schools did not have the budget for year-to-year maintenance on natural grass fields and would be forced to cut out aerations, topdressing, fertilizer applications, etc., yet several of these school districts had synthetic fields," Daviscourt said. "Turns out it is easier to raise money for installing a new synthetic field than it is to raise money for improving maintenance on the grass fields they already have."

If a field is receiving so much traffic that it frequently experiences turf loss, synthetic fields may be a better choice, he said. This assumes that the amount of traffic is so great that additional fertilizing, seeding, aerating and topdressing does not adequately improve the wear tolerance of the field to make up for the amount of traffic it receives.

In a common scenario, a natural grass field is used both for games and for practices causing significant turf loss because athletes return and drill in the same location every day. Solutions for this would be to talk with coaches to get the team to rotate though drilling locations on the field and move the goals for every practice; provide or find a practice facility to relieve traffic on the game field; or have property dedicated to sod production to repair frequently used areas of the field such as the center, goal mouths, penalty or free kick areas, where the shortstop stands, etc.

Daviscourt said access to water is a much simpler decision-making factor.

 

"In areas where water is limited and causes turf loss or dormancy during the playing season, synthetic fields may be a better choice," he said. "In areas with an over-abundance of water, where loss of surface stability and muddy conditions are commonplace, synthetic may be a better option if intensifying cultivation practices and improving the drainage doesn't compensate."

 

If he were in charge of a facility that could use one type of field or the other, or both, Daviscourt said he'd choose both.

"I would offer the synthetic surface for the practice events," he said. "If I had two fields, one natural, one synthetic. I'd rent out most of the practice times on the synthetic and then I'd use the natural grass for the games. The synthetic turf, with the amount of use you can put on it, fills that requirement very well. I'd use synthetic for winter events. December through March here in Oregon you really can't use natural turf because of the amount of rain and the temperature slows down growth, and so I would close the natural grass field in the winter. Natural grass would be for games and overflow practice. Synthetic would be day to day."

One Size Does Not Fit All

David Nardone is sport group leader for synthetic field manufacturer Stantec and a member of the board of directors of the Synthetic Turf Council. He said there is no one-size-fits-all strategy and set of tactics for field choice and use; climate and usage patterns are unique to regions and facilities and communities.

There is general advice for those on the cusp of decision-making, however, especially when leaning toward synthetic. Once the choice is made, there are common sense steps, Nardone said.

"Hire an experienced independent consultant to help you through the process to get the quality product for a fair price," said Nardone. "Follow the manufacturer's recommendations to start. Make adjustments to your routine based on the level of use on the field. Consult the manufacturer and installer, use them and your consultant as a resource. Based on how your facility is used, you should come up with the best practices and maintenance schedule."

Nardone said there's a synthetic option for all budgets. For tighter budgets, SBR rubber—recycled tire—is a proven product and a durable fiber. Combined with good carpet construction and with safety pads, it's a solid product. On the high end, monofilament fiber, alternative infills and high-performance safety pads will raise the cost considerably, but should be considered based on the level of play or for a stadium or high-level soccer facility.

For communities worried about potential health hazards using rubber tire infill—studies on the hazards have disagreed and as a whole been inconclusive—Nardone said there are alternatives, but, "We caution our clients on these new materials, and always advise them to seek the most proven alternatives."

One of the new options for end-users is field safety pads, Nardone said.

"With greater awareness of concussions, people are finally focused on the field safety," said Nardone. "We have been recommending pads for years; not only do they create a safer playing surface over the life of the system but they provide better field surface performance."

Nardone agrees with Daviscourt on field usage; the biggest difference from natural grass fields is related to available hours of field use.

"Natural grass limits the hours of play it can support, based on the type of field construction," Nardone said. "Synthetic turf fields can support almost unlimited use with half the maintenance, no fertilizer and no water. The con for synthetic turf is surface heat in the warmer months. However, we have technology to help mitigate these surface temperatures."

In the Field

As manager of athletic turf and grounds for Iowa State University, Tim VanLoo oversees both kinds of fields in a four-season climate. VanLoo, president of the Sport Turf Managers Association, is in charge of 55 acres of grass fields and two synthetic fields.

VanLoo said in addition to climate and usage and material, fields must be differentiated by sport. In his experience—three years as associate director of facilities at Northwestern University and almost seven years at Iowa State—the two types of field have benefits and blemishes according to activity.

"Football's all about traction," he said. "If the footing's good then it's going to play safe, typically. I can't have the field ripping up; it's got to be able to have a 200- to 300-pound person make a cut, and push on another individual that's of equal weight and not tear up, so the focus there is all about stability.

"On a softball field though, the athletes aren't very heavy, they don't make real big cuts and they kind of stand in one spot. The grass appears untouched, so there it's all about consistency and ball roll is more the issue than footing and stability. The management ends up being very similar because of watering and mowing, but the way it's used is very different, and the way I watch the game is very different just because I don't need the same footing in football as I do in softball.

"Soccer's kind of a similar thing. It's about footing and stability, but you also have the ball roll that has to be consistent and true."

VanLoo said there's no doubt that natural grass fields require more attention than synthetic, even with the increased and more varied use on synthetic fields. For synthetic fields—one indoor and one outdoor at Iowa State—VanLoo and his staff groom the indoor field two or three times a month during football season and less in the winter when multiple sports use it to prepare for spring campaigns. He said the indoor field isn't used much in the summer. The outdoor synthetic field was new in 2012, while the indoor facility was built in 2004, and resurfaced three years ago.

"You're almost playing more janitor than turf manager," he said. "You pick up garbage. The reality is they're less maintenance for sure. Not maintenance-free but less maintenance."

In Season

"I always tell people I'm a city farmer," VanLoo said. "Growing up on a farm I had a very similar schedule: We're really busy in the spring, then my really busy time, the harvest, is the football season. Winter is for getting equipment ready. Oil changes, getting books ready. Clean the shop, reorganize, get more efficient for the next year, tree trimming on a golf course. A slower pace."

Other than the multiple seasons, the windiness of Ames, Iowa, is a daily concern for VanLoo, more so than it was on the eastern shore of Lake Michigan.

"A lot of it has to do with moisture management," he said. "In the summertime when you get low humidity and really windy, it's a bad combination. A plant's going to transpire at a rapid pace. Before working here I never really looked at wind on a day-to-day basis, but now I do. You just factor that in and try to make sure you irrigate in the early morning when the wind's not blowing. It affects more what we can do that day, how we paint the fields."

The winter-to-spring transition is different every year, said VanLoo, adding that he doesn't work outside until the temperature reaches 40 degrees. The first softball game is in March, and most early games are on road. The Iowa State softball stadium was built in 2011, with the climate in mind; it is sand-based and does not have a freeze-thaw cycle, so as soon as the ground is not frozen, the field is ready. The dirt part is hydrophobic, meaning it doesn't let moisture in, and thus, it doesn't freeze either.

"Getting the facility ready, I've had to remove snow," said VanLoo. "I've dealt with areas of frozen warning track. You throw salt on it. We try to forecast the weather and react to it because I just don't know. What I tell the coaches is, 'Unfortunately the field doesn't look great until the season's done. Grass doesn't come out of dormancy, growing and recovering, until the last weekend'."

Know Your Stuff

As you'd expect from a STMA president, VanLoo is progressive with natural turf management techniques and tools. After a talk on fraise mowing at the annual STMA event, VanLoo tried it at Iowa State on an older practice field.

"A really cheap way to renovate the field," VanLoo said. "Had great success with it and it's played really well since. Another tool we hadn't had before we're able to use now."

For the past four years, VanLoo has used GPS technology for more efficient spraying and a TDR probe to better gauge field moisture levels. VanLoo said a TDR probe can be as much as a $1,200 investment. To employ GPS, $8,000 to $10,000 is needed at least, going up to $20,000.

"(The TDR) allows me to get game-ready with certain moisture levels, make sure we're not wilting anywhere," VanLoo said. "It's allowed me to really utilize water more efficiently and only when needed. I've just tried to stay up with the technology that allows us to be much more scientific about our approach instead of just kind of, 'Hey, I think.' It eliminates some of that thought process—the should I or shouldn't I—and allows us to be more precise."

VanLoo's staff is all students—some experienced, some green. He said that they all end up doing everything because there is no full-time staff. VanLoo has a teaching and executive style with them.

"You're going to make mistakes, so try to understand what the mistakes were and not repeat them," he said. "The best learning experience is typically a mistake. I try not to allow those to happen on game fields. A lot of it is just slowing down. Just slow down and make sure we get the job done right the first time so we don't have to come back.

"I encourage all of them to use their education, use what they're seeing, to come back with ideas. I've had to change some of my old ways with what they've come up with. I try to have them learn what we do then use their brains to see if there's a better way. I have a program I stick to and I tweak every year. You're always trying to get incrementally better."