You've gotta roll with it!

"Some guys are still seeing how low they can go because it's the macho thing to do"
Thom Nikolai, Ph.D., Turfgrass Academic Specialist, Michigan State University

As the debate about green speed rumbles on across various websites within our industry, and our good friend Greg Evans at Ealing Golf Club continues his quest for a 2mm cutting height, our colleagues in the United States have taken another route to pander to golfers' wishes. That of turf irons to achieve green speed.

Of course, many would argue that consistency across all eighteen greens is far more important than speed, especially given the penchant for more undulating greens on modern courses, but the wishes of the golfer appear paramount. Even the home of golf, St Andrews, is a convert to turf irons.

"Fifteen years ago, golf course superintendents were much more apprehensive about rolling their greens than they are now," says Thom Nikolai, Ph.D., a turfgrass academic specialist at Michigan State University, who has been conducting rolling research since 1994. "They were saying, 'No way those machines would be on my course,' because they were worried about compaction and bruising the turf."

However, research has changed their apprehension and, today, superintendents are rolling greens more than ever. "Most superintendents I know roll at least three days a week," says Thom.

Fifteen years ago, Bob Bittner, certified superintendent at The Club at Pelican Bay in Naples, Florida, was rolling three times a week and was worried about compaction and wear and tear. Now, he's rolling the TifEagle bentgrass greens daily. "Everyone is rolling more than they used to," he says.

The increase of rolling frequency is, primarily, for two reasons; green speed as driven by golfer expectations, and healthier turf, through higher heights of cut and moisture reduction. "Lowering the height of cut caused rolling to become more popular," says Shawn Emerson, director of golf at the six-course Desert Mountain Club in Scottsdale, Arizona. "We were already at such low heights that I didn't want to lower any more just to create speed."

MSU research and turfgrass scientist James Beard, Ph.D., solidified Shawn's views about rolling. "He's the one that really okayed rolling for me. I also talked to the PGA Tour and folks like Marsh Benson (Augusta National) and Matt Shaffer (Merion Golf Club) - the people who did a lot of rolling."

The need for speed

Shawn began rolling regularly in 2000-2001 when the green speed was 10 on the stimpmeter. Throughout the past ten years, he began rolling more - three days a week - and now he's rolling more than ever. Expectations have risen along with the target green speed, which is up to 11. "If we want to really speed up greens for a special event, we'll roll every day," he says.

At Pelican Bay, the course's green speed is 10.5 daily. During tournaments, it's about 1 foot faster. Because the greens are undulated, speeds of 12 to 12.5 are too fast, Bob Bittner says.

Patrick Santerre, superintendent at the 18-hole Le Diamant Golf Club in Mirabel, Quebec, generates 10 to 12 inches on the Stimpmeter as a result of rolling. Because Santerre's course has 12 push-up greens (Poa annua) and six USGA-spec greens (bentgrass), it's difficult to achieve consistency between the two types, so he plans to roll the push-up greens five times a week compared to four times a week for the USGA greens, which are faster because of their construction. However, rolling - which provides a better, smoother ball roll and a more even putting surface - can lose its impact as the day progresses. Shawn's greens will lose twenty-five percent of their roll during the day. So his staff roll the greens at 8.00am and the green speed is 11.6. After the springboard effect goes away, the greens end up at 11.2. "There are 108 putting greens at Desert Mountain, and every one is within 3 or 4 inches," Shawn says.

How high can you mow?

Many superintendent have raised mowing heights as a result of more frequent rolling. "Some guys are still seeing how low they can go because it's the macho thing to do," Nikolai says. "Now I think it should be how high can you mow." Nikolai cites Mike Morris, the certified superintendent at Crystal Downs Country Club in Frankfort, Michigan who used to mow greens at 0.115 of an inch and now is at 0.145. "He's rolling every day, and everyone is happy. There's less stress on the turf."

Shawn Emerson started playing with mowing heights based on speeds. From November through February, when there's less light, high traffic and slow growth, he likes to raise the height of cut. He also doesn't want to lower fertility on the greens during the winter. "Rolling is more about raising the height of cut than green speed," he says. "I'm never below one-eighth of an inch."

Scott Griffith, superintendent at the University of Georgia Golf Course, hasn't raised the height of cut on the course's Dominant bentgrass greens yet but plans to. He'll keep the height of cut low until the end of April after he hosts the PGA Tour's Nationwide tournament. Presently, the height of cut is 0.115, but 0.140 is the goal, yet 0.135 is more realistic, he says.

Cultural benefits

Another result of frequent rolling is less disease (dollar spot, anthracnose and brown patch) because of a higher height of cut and less moisture. "It's a moisture-management issue, and it's a big issue." says Shawn. He watches the tyre pressure on the triplex mowers carefully when rolling because he doesn't want to leave marks on the greens. He also says a key point is not to roll if there's frost because you don't want to crush the plant's crown.

Years ago, compaction was a big worry among superintendents who were apprehensive about rolling. Now, rolling only affects the top inch or inch and a half of the profile. Scott Griffith says many superintendents aren't concerned about compaction because they have USGA-spec greens, but those who have push-up greens might be more concerned. Rolling puts less stress on greens than mowing.

Economic impact

Superintendents can save money by rolling more and mowing less. Less mowing means you don't have to backlap or sharpen reels and change blades as often. "The cost savings would pay for a roller in one year," Thom Nikolai says.

Scott Griffith says the main reason he rolls is economic, saving on labour because he doesn't mow as often. He also rolls after topdressing, so there's less wear and tear on the mowers. By eliminating mowing just once a week, Bob Bittner saves twenty-four hours of labour (eight mowers used for three hours).
What's right for you?

When it comes to a particular rolling programme, superintendents are figuring out what works best for them based on weather, type of turfgrass and green construction, golfer expectations and budgets. There's no one right way to roll, noting that time of year and region of country affects rolling.

"Rolling is a good PR tool," says Patrick Santerre. "They see us rolling and automatically think the greens are rolling faster. It's golfer perception. Golfers appreciate the game better when greens have been rolled. They like to see us rolling because neighbouring courses also are rolling."

Bob Bittner suggests rolling is going to change every golf course, but that "superintendents need to roll to meet their desired speed range. They should look at not mowing every day. I never thought I'd be rolling as much as I do, and we're not seeing a detrimental effect. Rolling is a partnership with the greens programme."

And what of St Andrews? "We have been using the Tru-Turf rollers for four years now," says Course Manager, Gordon McKie. "They are an essential tool in maintaining green speeds. We use them all year round, and even more intensely in the run up to a tournament like the Open."

"We have three hectares of greens on the Old Course, so we have two dedicated machines here and a further six used at the other Links Trust courses."
The rollers aren't just confined to greens. "We use them on surrounds to smooth them up, and we also roll in winter after aeration to get the greens back in play with minimal disruption to members."

Gordon believes that greens rollers are the single biggest innovation in greenkeeping in recent years. "As well as offering excellent presentation, it makes for healthier turf as cutting heights do not have to be as short to maintain green speeds."

This article first appeared in the April 2010 edition of Golfdom magazine and is reproduced here by permission. Additional material supplied by Pitchcare