Features Agronomy
Don’t forget collars, approaches when maintaining golf greens

ISSUES pertaining to golf green collars and approaches and surface drainage were front and centre in early July at the Hamilton Golf & Country Club, whose turf care department played host to a science and technology field day.

Headlining the day’s speakers were the University of Guelph’s Dr. Eric Lyons and the Chimera Group’s John Bladon, both members of the Canadian Turfgrass Advisory Group, who addressed those issues and others.

Lyons said golf course superintendents have become good at managing their greens, and in most years they are outstanding in quality.

“But something gets caught in the middle oftentimes, and that’s your approach. It’s your approach up to the green…the collars around the green. Sometimes there are issues with that because we’re applying materials that are meant for the green that are being oversprayed onto the collars, and we get interesting responses.”

Superintendents will often not pay enough attention to these areas, he said, adding how the approach is treated will greatly impact upon how the golf ball will respond.

“One of the things we’ve been looking at is extending your greens maintenance or topdressing program down into your landing area or approach, especially if a lot of your golfers are going to be landing short. Senior guys like that hop-up. The single-digit handicappers like that thunk-check, and they can play that low ball in on a windy day. That’s one of those things we’ve lost track of with target golf and the high ball and all that.”

Lyons said there has been a push back to the roots of golf which includes getting sand into areas that allow the ball to skip and check. He added the tactic might also help with other issues superintendents are trying to maintain on their greens on a long-term basis.

A penetrometer tool is useful for determining ball reaction. Essentially “a pressure gauge mounted on a stick,” Lyons said the tool tends to be rarely used properly. It must be provided constant pressure in order to feel the layers. The harder it is pushed, the more it spikes, and a harder push yields more resistance.

Bladon said what the penetrometer is able to achieve vs. a soil probe is the production of “real numbers” that show trends and puts the superintendent in a more powerful position when dealing with “bean counters.”

Lyons said golfers tend to walk along a green’s fringe while carrying their clubs instead of walking straight across the putting surface. This practice contributes to excessive perimeter wear, resulting in differential activity with some applied chemicals.
More perennial ryegrass is entering collars these days because superintendents are regulating the growth of the species they want and not regulating the growth of the “weed” in collars, he said.

Primo, for example, is used on greens for its array of benefits, but is typically sprayed off into the collar.

“So the collar is receiving something that encourages the weed—perennial ryegrass. We don’t have to worry about perennial ryegrass on our greens because it won’t survive the mowing height.”

New-generation perennial ryegrasses can be mowed down to a height of a quarter-inch without problem, Lyons said, and they will survive and be competitive at that height.

“When you get into the collar, you’re definitely dealing with that.”

Lyons said he likes to study the competition among plant species, noting that on a green there will be different aspects visible of where the poa survives, where bentgrass survives and where there might be winter kill.

He has been utilizing a grant through the Canadian Turfgrass Research Foundation to study the physiology of winter kill which he said has a direct link to poor surface drainage.

The famed Canadian golf course architect Stanley Thompson paid particular attention to surface drainage, Lyons said, adding that when looking at greens a superintendent should wonder where water will come off the surface.

“Where is the water supposed to shed? Are there any areas that will not shed? Those areas that don’t shed are where you’re going to get your winter kill.”

Members can be forewarned ahead of time because carefully mapped greens indicate where there is insufficient water surface drainage. It also allows superintendents to critically look at their collar dams where the sand has moved into the collar and will wash across the canopy during a heavy rainfall or through irrigation after topdressing. When it hits the thicker collar, it stops.

Collar dams are thus created, and there is likely to be more bentgrass in those areas because poa will be killed more often in the winter.

Areas that have good surface drainage have tight poas, Lyons said, while areas with poor surface drainage, where there may be winter kill every five to seven years, have coarse, seedy poas.

When these patterns emerge, it is easier to map out where there is likely to be problems in a bad year.

Lyons said he has an interest in poa-bentgrass mixes, and spends a lot of time studying that in his lab.

One of the best things a superintendent can periodically do is go out with a transit and shoot some grades onto areas where there are collar dams, Bladon said. At whatever frequency they can afford to do that—in terms of managing risk in those areas—getting out with a transit and physically shooting some of the gaps between the collar and physical green site is going to provide helpful information.

He said to trend in the right direction with topdressing and other materials or the collars will be targeted to be pulled up, grades will need to be changed and regrassing will be required.

Lyons said he has seen some “amazing” ways to deal with “bird baths” and areas where there is a dam yet where the entire collar can’t be redone. An example is cutting a sod strip out and ensuring there is positive surface drainage down the strip. He added he has seen instances in which a superintendent has rolled it up, put it in his nursery and rolled it back out, marking which side was which and putting it back into the exact same spot so that everything matches up. This ensures the poa-bentgrass line remains continuous so as to avoid an eyesore.

In a “bird bath” situation, the root zone may drain fine, but if the ground is frozen it won’t drain.

“It takes so long for our soils to warm up in the spring that we don’t get that drainage through the root zone,” Lyons said. “We have to rely on positive surface drainage.”

Bladon said it is important to collect physical data associated with putting greens, whether they are native pushup greens that have accumulated a topdressing cap or brand new bentgrass surfaces in which the superintendent is monitoring the organic matter on top and keeping an eye on what is happening.

Water quality in Ontario is for the most part substandard, he said. With soil testing, there is usually a focus on manganese and its association with soil values because take-all patch is so commonplace in the province. He added there is a pool of data that is building with regard to take-all patch that increasing water-soluble manganese levels beyond soil test data will actually provide the damaging bacteria food source negating the damage.

Sulfur is important to note, Bladon said. Many don’t recognize that a lot of the material they purchase from their suppliers typically contain a sulfur byproduct which compromises root development.

“You buy manganese, you’re buying manganese sulfate. You buy potash, you’re buying sulfate of potash.”

Lyons said most soils in Ontario are slightly sulfur-deficient, allowing for the ample application of sulfur for an extended period of time before the buildup and detrimental effects of excessive sulfur in the root zone are seen. Over the past five to seven years, he said, superintendents have increased their amounts of sulfur as a byproduct of the popularity of ammonium sulfate applications as well as increased amounts of potash, manganese and magnesium.

“We’re applying more and more of these things and more and more sulfur,” Lyons said. “It may never catch up to you, depending on your soils, but in some places it absolutely will, and you have to be aware of that.”

Bladon said with most USGA sand greens that percolate well, there will never be a problem. A lot of those sulfates will move quickly through the system and never cause an issue. But as drainage and percolation and infiltration slows, sulfur starts to pile up, creating a toxic environment for bentgrass and promoting ample annual bluegrass.

The science and technology field day also provided attendees with data collected from trial plots on which Velocity herbicide was applied. The herbicide controls annual bluegrass and suppresses dandelion, dollar spot and white clover.