Keeping track of the dirt at Canterbury Park

Michelangelo worked in marble, sculpting men from blocks of stone. Georgia O'Keeffe made flowers bloom by putting paint to canvas.

Like those masters, Johnnie Jamison has his preferred medium, too: the stuff underneath his boots on the Canterbury Park racetrack. It looks like plain old dirt to most. In the hands of the track superintendent, though, it's an ever-changing substance that holds the key to maximizing a horse's safety and speed.

"It's just like an artist working with clay, where it has to have the right amount of water to become the vase that he wants," Jamison said. "You have to get past the idea that it's just dirt. The racetrack is a living, breathing thing."

Most casual fans paid little attention to racing surfaces until recent months, when 30 equine fatalities at Santa Anita Park made national news. Many trainers blamed the track's surface for the catastrophic injuries, saying it was compromised by unusually heavy rain in Southern California.

At Canterbury, Jamison oversees a 1-mile dirt oval that was fully renovated last fall. Track officials spent $100,000 to restore the limestone base to its original specifications and rejuvenate the top layers of sand, clay and organic material.

State veterinarian Dr. Lynn Hovda said the investment is paying dividends. No horses have suffered fatal injuries while racing at Canterbury during the first eight weeks of the season; two have died during training, though Hovda believes those horses had pre-existing problems. Compared to last season, fewer horses have been placed on the veterinarians' list of those barred from racing, and there have been fewer calls for the horse ambulance.

"The track is so much better than it's been in years," Hovda said. "And that's one of the most important features we have as far as preventing injury."

"I keep my windows open, and I'm looking at that racetrack 24/7," he said. "It's a cliché, but it's a labor of love. And it has to be."

Over the past 25 years, Jamison said, surface management has evolved into a highly scientific pursuit. Track superintendents have a better understanding of how surfaces affect horses' health and more tools to make them safer. Their work combines principles of physics, geology, biomechanics, engineering and good old-fashioned horsemanship.

Tuesday morning, Jamison awoke at 2:30 a.m. to check the amount of moisture in the surface of Canterbury's main track. Based on his findings, his crew used a harrow — a rake-like implement pulled by a tractor — to fluff the top layer to a depth of 3½ inches. That soft, loose surface would be just right for training, giving horses a good workout while being gentle on their legs.

Jamison said a pristine surface produces fewer injuries, so Canterbury grooms the surface twice during morning training. It takes a dozen people, four tractors, four water trucks, two graders and multiple harrows and rollers to keep the track in tiptop shape.

"This is the one variable that every horse touches on a day-in, day-out basis," said Andrew Offerman, Canterbury's director of racing. "It's important that we do everything we can to make sure it's as safe as possible."

The safest dirt tracks are soft enough to cushion the impact of a 1,000-pound horse racing at 35 mph, yet firm enough to support its hoofs as it propels itself forward. The footing needs to be uniform; if a horse feels the surface change under its feet, Jamison said, it may hold back from giving full effort.

A good surface will retain the right amount of moisture, while draining properly and maintaining its integrity when it rains. A too-hard surface can cause soreness and injury to horses' delicate legs; one that is too soft or deep can lead to soft-tissue injuries.

Many horsemen suspect the Santa Anita fatalities are linked to the heavy rains, which led to the track being "sealed" — packed down to keep the rain from penetrating — over and over, making it harder than usual.

Hundreds of horses train over the Canterbury oval every day, in all types of weather. That means the surface is constantly changing, requiring Jamison to monitor it intently and adjust it as needed.

He has tools to test things such as the depth, compaction rate and moisture level. He also uses his eyes and ears. By watching a horse's stride, Jamison can tell whether it is comfortable running over the surface, while the sound of hoofbeats indicates whether it has the right amount of cushion.

"The biggest concern of the horsemen, and the thing that gets the most complaints, is the racetrack," said trainer Tony Rengstorf, a board member of the group representing Canterbury's horsemen. "It is a huge, huge part of racing. I've been here almost every year, and it's probably as good as it's been since the beginning."

That's the greatest praise possible for Canterbury's resident soil savant. But Jamison knows his job is never truly done. Shortly after the tractors groomed the surface during Tuesday's training, he already was noticing the effect of the wind and the sun, and thinking about when to send out the water truck.