Answer Man

How do they get the grass to look like that at Busch Stadium?

The Busch Stadium grounds crew will sometimes have a Gateway Arch symbol appear in the outfield, thanks to a special mowing pattern.
The Busch Stadium grounds crew will sometimes have a Gateway Arch symbol appear in the outfield, thanks to a special mowing pattern. Joe Ostermeier

Q: When they cut the grass at Busch Stadium, how do they get the grass to look like the stripes on a watermelon? I sometimes see this on business lawns and residences as well.

G.L., of Collinsville

A: With all the amazement these often intricate ballpark designs can elicit, I feel like a magician about to explain his top-secret trick.

But, really, there’s no mystery, says David Mellor, the Boston Red Sox director of grounds, whom some call the father of this art of turf painting. With the right grass and a little extra equipment, anyone can become a backyard Picasso.

In fact, you’ve probably gotten a small taste of what you can accomplish. Have you ever looked at your yard, say, from an upstairs window after a fresh mowing? Don’t the tracks left by the mower’s tires seem to be a slightly different shade of green than the grass in between?

Well, there’s your answer. By running the wheels over the grass, the weight of the mower has temporarily bent the grass in a new direction that reflects the light a little differently. If you’re looking at it from a vantage point, the rule of thumb is that grass bent away from you will capture more light and appear to be a paler green. Blades bent toward you will reflect less light and appear darker. Those not bent will come up somewhere in between.

This is no news to housekeepers. If you run a vacuum cleaner over a plush rug, you’ll see slightly different shades depending on your vantage point and which way the vacuum has rolled. And, of course, the last time you put on your velvet smoking jacket, you surely noticed how you could change the shading by running a finger back and forth over the nap.

Ballpark designs merely borrow from this concept in jumbo proportions. With a mower, wide, heavy rollers and careful planning, groundskeepers throughout the world of sports can produce almost any design they put their mind to.

“The patterns are limited only by your imagination,” Mellor says on an explanatory YouTube video he did with Wendy Bounds of the Wall Street Journal.

It’s nothing new, he says, noting that mowers have been leaving unintended patterns in grass since they were first built. But in 1993, Mellor may have started grounds crews on what now seems to some as a never-ending contest of one-upmanship. He was an assistant groundskeeper at Milwaukee County Stadium at the time when a concert left the grass in the outfield looking like a Phyllis Diller hairdo. After getting approval from his boss, Mellor mowed in a busy pattern as a sort of camouflage

As a result, fans started oohing and ahhing over the pattern and didn’t notice the damage. A new career as field-artist-in-chief was launched.

“I’m not looking for more work,” Mellor told the New York Times in 2008. “But the grass has to be mowed anyway. So why not do it well, with straight lines, or checkerboards, or something more festive?”

His office wall at the park is lined with photos of his handiwork. He has done designs created by his two daughters. One of his favorites was a pattern he copied from a tartan sweater. And, oh, yes, there was that time for a Bruce Springsteen concert when he spelled “Bruce” around the infield — with a B done in the Red Sox logo script. Did it make Springsteen Boston’s biggest fan?

“I think he was that day,” Mellor joked to Bounds.

It’s the same in St. Louis, where Cardinal head groundskeeper Bill Findley has been responsible for everything from those watermelon stripes to putting the city’s iconic Gateway Arch in the grass.

If you weren’t aware of the routine, the Redbird crew spends between 45 minutes and an hour each day cutting the grass. (In Boston, they cut about 65,000 square feet — about an acre and a half.) They use three mowers — a lighter one for the more heavily trafficked areas in the infield and two heavier ones for the outfield. By planning the designs and using heavy rollers to bend the grass, they can produce the patterns that have fans talking while waiting for their idols to take the field.

Checkerboards are easy, he says. Just start at a foul line and work your way across the field. The most rewarding designs, of course, take a lot more work.

“For the Arch, we did an actual diagram,” he said on his YouTube video. “We’ll have some tape measures that we’ll bring out. We’ll measure from first to third. Then, we’ll pull a string line right down the middle and we put flags. And we’ll keep following these flags until we get the pattern burned in enough where we can remove the flags and see the pattern.”

Just one potential danger.

“Unfortunately when you’re mowing these patterns on a daily basis, you get to where you’re wearing grooves in the grass, so that’s why we switch the patterns up quite a bit so that the grass doesn’t get used to each pattern,” he explained. “If you keep the same pattern, the ball will snake really badly and the outfielders don’t like that, so we try to switch the patterns up to keep the grain out of the grass.”

Anyone with the desire and energy is invited to try this at home, says Mellor, who literally wrote the book on the subject: “Picture Perfect: Mowing Techniques for Lawns, Landscapes and Sports,” which is available on Amazon and elsewhere. With a basic lawn and garden tractor that has a cheaply made roller behind it, you can be the envy of your less industrious neighbors.

“All it is really is grass being laid in different directions so the sun reflects off it differently,” Findley said. “That’s why you get the different shades. When you come to the ball park, hopefully it’s one of your favorite things. Just know that we enjoy doing it.”

Today’s trivia

Who was granted the first patent for a lawn mower? When?

Answer to Saturday’s trivia: When British astronomer Sir William Herschel discovered the solar system’s seventh planet in 1781, he wanted to honor his country’s king by calling it George. Can you imagine? There’s Mercury, Venus, Earth, Mars, Jupiter, Saturn and George. Fortunately, wiser heads prevailed and it was eventually called Uranus after the ancient Greek god of the sky. However, Herschel was given sort of a runner-up prize. He asked that any moon discovered be named after the characters of Shakespeare and Alexander Pope, so today among Uranus’ 27 satellites are Portia, Julia, Desdemona and Puck.

Roger Schlueter: 618-239-2465, @RogerAnswer