Feature Article - February 2007
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Turf Wars

How to win the battle against overuse and other enemies

By Kyle Ryan

Recovery and aeration

Advances in science get all the headlines, but McAfee said that the biggest improvement he's seen in turfgrass over the past decade is decidedly unglamorous: better management. It sounds boring, but even the best field with the strongest grass, highest-tech irrigation and drainage, and most vigilant anti-pest regimen will have problems if it's managed improperly.

It could be as simple as mowing. In its Sports Turf Industry Fact Sheet, the Sports Turf Managers Association cites frequent mowing as essential for healthy turf because it "reduces scalping, disease incidence and the need for sweeping, and it improves field performance." No one who took the STMA's survey mows just once a week: 21 percent do it twice a week, 30 percent mow three times, 9 percent mow four times, and 40 percent do it daily.

In Texas, McAfee advises field managers to maintain their Bermudagrass at a 1-inch height, maybe 1.5 inches.

"In years past, they would mow it at 2 inches, 2.5 inches, 3 [inches] once a week, and it'd wear out in no time," he said. "If you mow it at 1 [inch] three times a week, it'll last at least twice as long, if not longer."

Frequent mowing creates thicker grass, whether it's Bermudagrass in the south or bluegrass up north. The key, McAfee said, is never to take more than 30 to 40 percent of the leaf tissue off at once.

"When you remove excess leaf area, you inhibit the plant's ability to produce food that it needs for new leaf growth," he said. "So the more often you mow it, the less leaf area you remove, the better quality grass you'll have."

Another big change in management practices comes from aeration, the process of putting holes in the soil to allow air and water to reach it more easily. More field managers are realizing the importance of aeration, particularly with high-traffic fields.

"When you use fields, you've got a couple consequences," Chalmers said. "One is you have a physical abrasion of the grass, and the other is compacting the soil. The compaction is a very subtle thing that isn't nearly as obvious as if you have a soccer tournament one week, and all the goals wear out on the surface from the play, as an example. All the compaction's there, and it's harder for the grasses to recover the more compacted the soils are."

Aeration loosens up compacted soil, allowing nutrients to penetrate growth areas. Of course, aeration needs vary according to the field and who uses it: adults or kids, soil type, how often it's used and so on. Most runners don't do a marathon one day, then do another one the next, and natural turf shouldn't be expected to, either. It is, after all, a living organism with limits, just like any other.

"Unfortunately, most cities are just hurting for space for leagues to play," McAfee said. "[The grass] just never has the opportunity to recover. Any time you have excess use, I don't care how good your field's built or maintained, when you get excessive wear on the grass, you will wear it out."

A big public park like Central Winds Park in Winter Springs sees a lot of action, so it requires a turfgrass that can handle everything from baseball to cars parking on it. While much of the park uses Bermudagrass, park managers decided to try something new when they acquired 27 new acres: seashore paspalum of the low-growing sea-dwarf variety.

"We had heard about seashore paspalum in terms of it being a new grass, and what we heard was that it was a very tough grass," Pula said. Before committing to an untested grass on the new acreage, Pula and the parks department decided to try it out on a different park's football/soccer field. What they saw pleased them.

"We found that it was a very tough grass—it handled abuse in our opinion as good as or better than Bermuda," he said. "We really liked that we could salt it for weed control by using plain solar salt, the type that goes in water-conditioning units—it's a relatively inexpensive type of weed control. We also liked that it had a longer dormant season than the Bermuda; it seemed to go longer into the fall and start earlier in the spring than the Bermuda did."

Salesmen also touted the paspalum's need for less water than Bermudagrass, but Pula and company haven't found that to be the case (though he did explain that it needs less nitrogen in the fertilizer). It also has a tendency to clump in what the staff refers to as a "witch's broom," where the grass grows tighter and thicker. It's easily treated with more mowing and aeration, though addressing a Bermudagrass invasion at the fields' fringes has proved a little more difficult. The staff uses salt and herbicides to eliminate the Bermuda, but it has a tendency to creep back with time.

Still, paspalum's toughness is something to behold. For Central Winds Park's July Fourth celebration, Pula estimates 850 cars parked on the fields, with more than 30,000 people in the park itself.

"You could see some wear in travel lanes, but as far as where the cars parked, you'd see a little bit of burn where somebody may have been running their car a long time or a few oil spots, but it was really minimal when you looked at it. If you didn't know any better, you'd never know there were 850 cars on this thing for a whole day."

In chess, winners prevail by thinking several moves ahead. Chalmers advises a similar strategy when it comes to wear: Plan ahead for preventive maintenance.

"[There's] concentrated traffic and trampling in between the hash marks in football and the goal marks in soccer—you can't alter that traffic pattern, so you need to stay head of it in doing practices before problems develop," Chalmers said. "Management has to be proactive in cultivation and fertility so they stay ahead of declining quality. Once you have a field starting a decline, it's much harder to bring that back than it would be to bring the preventive maintenance all along the way to have it healthy and keep recovering."