UF Researcher Develops Guidelines For Soccer Field Performance

July 6, 1998

GAINESVILLE—University of Florida researcher Grady Miller may be a popular man in soccer circles by the time the World Cup rolls around again in four years.

Miller, a turfgrass specialist, is beginning to answer a question soccer players have asked for years: Is there a way to get soccer fields, city to city and country to country, to perform in a similar manner?

Ten months into a research project on soccer fields, Miller says the answer is yes.

“Soccer fields vary drastically not only in grass but also in soil layers. Then you throw in management practices, which can drastically influence uniformity of the turf cover and surface hardness,” said Miller, a researcher in UF’s Institute of Food and Agricultural Sciences.

“There is a wide range of field performance conditions, all the way from bare areas that could be potentially dangerous to a player, up to world-class types of facilities.”

Until now, no one had an objective way of rating soccer fields. So Miller developed a method of measuring field characteristics, putting numbers on qualities that up until now have been subjective.

“Soft, hard, fast, slow. These traits have always been relative,” Miller said. “What is field hardness?”

To collect data, Miller first had to build a gadget called a soccer field gauge, similar to the devices that measure the speed of putting greens for golf tournaments.

The gauge is elevated, like a ramp, and Miller rolls a soccer ball down and measures how far and how true the ball rolls once it hits the turf. He also uses a Clegg impact hammer, which measures surface hardness.

Readings are taken at evenly spaced locations on the field so that Miller ends up with a rectangular grid of readings. By combining the data, he can quantitatively determine how soft or hard the field is and how uniform. Then he can recommend ways to correct the problems.

Ball roll readings from the Rose Bowl field, which drew accolades from players in the 1994 World Cup, are used as a standard. Those readings fell within a range in which players felt comfortable with the speed, distance and trueness of the ball roll.

The quest for uniform quality is the ultimate goal.

“Professionals want to know that the field they played in California will play the same as the field they’ll play across the country,” Miller said.

Most soccer fields, especially recreational fields, get so much play that hardness is the issue, not softness. And for parents, that means safety is an issue.

Preliminary data indicate a hardness reading of 90 to 120 is good and any reading higher than 140 requires corrective action. But on some recreational fields, Miller said he has taken readings of 200 or higher. Those fields remain in use because of the popularity of the sport.

Many recreational fields in Florida are not irrigated and are planted with drought-tolerant Bahia grass, which doesn’t make for the best playing surface. Many suffer from over-use, with bare spots and uneven ground. But without guidelines to follow, recreational directors have had few weapons to use in arguing for more money to maintain fields uniformly from city to city.

While the softer the field, the safer, the ball rolls farther and faster on a hard surface. So balance is the key. Without balance, the style of play must change with the surface, said UF soccer coach Becky Burleigh.

“A lot of times up North, especially in November or December, with sparse grass, soccer becomes an air game,” Burleigh said. “In the south, with our shorter Bermuda grass, we play on the ground.”

Burleigh said Miller’s quest to develop field standards is important because poorly maintained fields hamper the play of skilled teams.

“Field variations can create a tremendous home-field advantage for teams with a poor-quality field,” Burleigh said. “The field takes away from the strength of a visiting team that is fast and skilled and leaves more of the play to chance.”

With 250 million people playing the sport worldwide, Miller said a stronger interest in soccer fields is overdue.

“There has been little research on athletic fields, particularly sport-specific fields like soccer and football fields,” Miller said. “There are some unique aspects to soccer fields that really haven’t been evaluated before now. So we’re hoping to develop standards and be able to evaluate fields to improve their performance and level of maintenance.”

While Miller said the guidelines could be used as a management tool for football fields, they wouldn’t be as crucial.

“In football, the ball is in the air and the players are wearing pads,” Miller said. “In soccer, the ball is on the ground and the players have no cushion when they fall. The field surface is directly related to performance and how the ball reacts.”

Miller said he expects the interest in athletic playing fields to grow.

“Sports turf management for athletic fields is not as far along as golf course turf management,” Miller said. “But it’s advancing each year.”