 |
|
CSI: Turfgrass
Accurate disease identification is critical for today’s superintendents.
 |
Photo illustration by Kelly Neis and Roger Billings |
The profession has undergone many changes over time, but one of golf course management’s most basic responsibilities, identifying and responding to turfgrass disease, is as integral to a superintendent’s success as ever.
To be sure, managing golf course turf these days is rampant with cultural and control issues, playability ramifications and, yes, job security concerns. But the tradition-bound premise has endured and, in fact, has become even more relevant.
“Become knowledgeable about major problems you have to deal with and how to control those problems,” is the expert charge given to superintendents by Rutgers University’s Bruce Clarke, Ph.D., a turfgrass pathologist who has spent nearly two decades in education forums teaching the ABCs of dealing with those problems.
“It’s always a timely topic and good job security for a turfgrass pathologist,” says Clarke, who has teamed with Clemson University’s Bruce Martin, Ph.D., for the past 15 years at GCSAA education conferences to present a seminar on turf disease identification and management.
Clarke has also teamed with Richard W. Smiley, Ph.D., of Oregon State University, and Peter H. Dernoeden, Ph.D., of the University of Maryland, to author the third edition of a popular book among turf managers, the “Compendium of Turfgrass Diseases."
The “Compendium” includes a section on disease diagnosis. The authors stress the elements of knowledge, keen observation and accurate interpretation in diagnosing turfgrass problems. Those elements frame three basic steps:
• Understand the diseases specific to one’s region.
• Understand the conditions that encourage those diseases.
• Control with cultural or management practices, as well as a good chemical program.
Clarke and others featured in this article will explore those steps and their particular implications.
 |
Field days, attended by superintendents, researchers, assistants and others, are opportunities to view many different turf issues up close. Photo courtesy of BASF |
The eyes have it
One of the most important practices related to disease ID is developing an effective scouting or monitoring regimen, which Clarke maintains is crucial to understanding major problems in respective regions.
“That’s really important — keeping up every-day monitoring of the course and noticing what’s not normal,” he says, adding that superintendents who move to another venue should quickly familiarize themselves with the layout’s agronomics and possibly even solicit information about disease probabilities from various sources such as local turf educators, diagnostic labs and turf services such as Extension agencies and the USGA Green Section, as well as other superintendents in the neighborhood.
Clarke says monitoring relies on the ability to pinpoint trouble accurately. A good case in point is the combination bentgrass/Poa annua green, which can be found across the country. Both species are susceptible to a variety of problems. When disease is evident, the trick is to know which grass is ailing.
“Most diseases are pretty specific and don’t jump across species easily,” he says. “Invariably, it’s almost one or the other, and it helps to narrow the focus of the disease problem by knowing the proper host first and foremost.”
The importance of know-how
Kyle Miller, a technical specialist with BASF who works with a wide range of superintendents in diagnosing turf problems and finding the appropriate solutions, points to experience, or lack of, as a fundamental facet.
“There are superintendents who are inexperienced or lack education who rely on identifying a handful of diseases and then problems arise, usually as a result of changing management practices,” he says. “Then there are the upper tier, veteran superintendents who are educated and keep current through Golf Industry Show seminars and things like that.”
Both Miller and Clarke see experience becoming more of an issue because of the landscape in today’s turf management. Along with more intense, on-the-edge cultural or management practices due to owner and player demands, many courses also have multiple turf varieties in the quest for optimum playing conditions and aesthetics.
More so, Miller notes that in the Mid-Atlantic region and west along the transition zone, there are not only different types of grasses being maintained, but both cool-season and warm-season varieties to boot, such as bentgrass greens and bermuda fairways. These scenarios are at the mercy of Mother Nature and are breeding grounds for increased disease problems and increased frequency of disease.
The price of perfection
“We’re trying to elevate course conditions, and that has given rise to diseases like anthracnose. We also have a number of new diseases that have popped up in the last five years or so,” Miller says, pointing to problems such as rapid blight, Waitea patch and Pythium root dysfunction.
To the dismay of superintendents, anthracnose has expanded to cooler seasons because of more stressful year-round maintenance practices — lower mowing heights and fewer fertilizer applications on greens that are kept more dry and firm than ever before.
“I think meeting conditioning demands and changing cultural practices are reasons why we’re seeing more problems, such as stress-related diseases like anthracnose, which has been around for hundreds of years and has never been a major concern until about 15-20 years ago,” Clarke says. “Now in the last five to six years, it has emerged as one of the top three diseases around the country.”
While anthracnose is easy to ID, it’s hard to control, he adds. The answer is a challenge, and also quite possibly job-threatening in some cases.
“You must modify management practices and coordinate them with a good chemical control program,” Clarke says. “We’ve tried to help superintendents understand that often major changes aren’t required, but a little tweaking of their management programs can make all the difference in the world.”
 |
The soil moisture meter allows O’Connor to monitor the water content of greens and subsequently provide irrigation efficiency and uniform playing conditions. Photo by Paul Rieke, Ph.D. |
When in doubt . . .
Harder still are disease problems that are difficult to identify. Samples of root diseases like cool-season take-all patch and summer patch, and warm-season spring dead spot and bermudagrass decline should be sent to a diagnostic lab for affirmation or confirmation, Clarke says.
He adds that that doubt should also be eliminated from the choice of turfgrass disease control. “Identifying the disease only gets you halfway there,” Clarke says, pointing out that labs, Extension and university diagnosticians and consulting agronomists all can offer cultural or management recommendations as well as advice on chemical applications.
Miller agrees that unfamiliar turf symptoms should prompt myriad identification resources — including fellow superintendents, manufacturing distributors, even Internet searches. Chemical companies such as BASF also evaluate the interplay between disease and control. In all cases, time is of the essence.
“Generally speaking, I think we have enough fungicides out there that something is going to be specific enough that it will give control,” he says. “Turf diseases are related, but it does take time to hone in on exactly the best recommendations. We want to provide solutions as quickly as possible because we know it doesn’t take long for a superintendent’s job to be in jeopardy if they aren’t doing a good job of controlling problems on the golf course.”
In today’s age of so-called super grasses and their seductive call-of-the-sirens attractiveness, Clarke strongly suggests turf managers stay within themselves and be mindful of their respective territories by taking note of research results, such as those of the National Turfgrass Evaluation Program, and be drawn instead to grasses with tolerances to major diseases in their own region.
“There is no perfect grass ... no such thing as a turf variety 100 percent resistant to disease for all superintendents in every part of the country,” he says. “But there are better choices. It depends on where you are and what your major problems are.”
 |
Computers and turf diagnostic equipment can be fitted to complement each other. Photo courtesy of BASF |
An underlying factor
It’s no surprise that healthy soil is vital to the well-being of turfgrass. Thus, unsolved soil problems usually lead to turf disease.
“You could safely say soil problems play a role in the ultimate susceptibility to diseases,” says Paul E. Rieke, Ph.D., professor emeritus in turfgrass management at Michigan State University and the 1996 winner of GCSAA’s Distinguished Service Award.
For instance, Rieke, who along with the University of Georgia’s Robert N. Carrow, Ph.D., conducts an advanced seminar on detecting the physical problems of turfgrass soils at the GCSAA Education Conference, notes that high humidity and excessively wet soil will likely lead to brown patch and Pythium diseases, among others. By the same token, very dry conditions weaken the plant and foster various patch diseases. He adds that good drainage and a good irrigation program, respectively, generally solve those problems.
One thing is certain — superintendents, for the most part, have a better feel for soils’ peculiarities and issues than turfgrass maladies. And, as Rieke points out, many factors in identifying soil problems are obvious on the surface — too wet, too dry, compaction, etc. But, it’s what lies beneath that complicates matters and necessitates testing for soil types and internal drainage, which can vary greatly in USGA-spec versus push-up greens.
“Soil moisture has to be monitored very carefully,” Rieke says. “There is no perfect irrigation system. To me, one of the most difficult challenges for superintendents, with the variability in soils, is moisture management.” (For one superintendent’s take on the importance of soil conditions, see Page 74.)
High-tech is 20/20
There are tools to help turf managers “see” under the soil surface. Soil probes can check a variety of conditions, including internal drainage and moisture content. GPS is making inroads in the industry, and the technology can allow superintendents to record their monitoring process and other information such as soil moisture. GPS also makes mapping possible so most all members of a maintenance staff can take part in scouting.
The latter is important because identifying soil problems is likely to show that sensitive spots and areas that need more attention than others are found in several places on a golf course. It smacks of Bruce Clarke stressing local knowledge as a key ingredient to disease ID.
Rieke agrees: “You have to know your golf course ... I can’t emphasize that strongly enough ... understand where the wet areas are, what the traffic patterns are,” the 21-year member of GCSAA says. “You have to know what type of soils you have, from the effects of the construction of the course to nature’s variability.”
The relationship, then, between soil problems and turfgrass disease and their environment is evident. “It’s a total system and we have to manage the whole system,” Rieke says.
Co-pilots recommended
The popular notion is that a good many superintendents fly by the seat of their pants when it comes to identifying and dealing with turf disease.
Obviously, there is a considerable amount of barnstorming in golf course management. But, there also are legions of men and women coming into the profession who are highly educated in turf management and employ well-documented and calculating course scrutiny and disease diagnosis.
As the following case studies demonstrate, there are many superintendents today who rely on technology and relationships with trusted educators and consultants to reinforce what their eyes and their experience tell them.
Russ Myers, CGCS
Southern Hills Country Club, Tulsa, Okla.
Myers and Southern Hills, who are hosting this month’s PGA Championship (see the story on Page 56), have been together only less than a year, and considering what’s been happening — prepping for a major championship and all — that’s hardly enough time for Myers, as sophisticated and well-schooled as he is, to learn his course as the experts say he must.
“Based on my time here, I’m not fully comfortable diagnosing certain things that a pathologist can grasp and know for sure,” says Myers, who may seek out second opinions from as many as five sources.
To gauge just how thorough that makes Myers, consider that he has somewhat of a mini turf diagnostics lab right next to his desk at the Southern Hills maintenance facility — a microscope and related trappings. And he knows how to use it, having learned well during a stint as an assistant-in-training at Augusta National in the mid-1990s when he ran turf samples to Ed Brown, Ph.D., plant pathologist at the University of Georgia, for diagnosis.
“I became comfortable identifying many of the basic diseases of the time and continued to use the instrument and the process when I was superintendent at Key Largo (Card Sound Golf Club, 1998-2006),” says the 12-year GCSAA member.
Southern Hills has bentgrass greens, bermuda fairways and tees and bermuda/fescue roughs, not that unusual for a high-profile layout on the cusp of the transition zone. But after several years of managing TifEagle greens in Florida, Myers is, as he says, not all that comfortable yet.
Myers, who leans heavily on three assistants who have been at Southern Hills a combined 41 years, says the greens are monitored every day. “If we see something that we question, we bring it in and look through the roots, the leaf blades and the crown,” he says.
And, more often than not, he will run the samples by a number of others, including his old mentor, Brown, at Georgia. Other sources may include Lane Tredway, Ph.D., Extension specialist at North Carolina State who is very familiar with Southern Hills’ turf, university facilities at Connecticut and Rhode Island and Turf Diagnostics & Design out of Linwood, Kan.
Myers notes that utilizing his own diagnostic technology enhances the timeliness of the process. He has even achieved a quicker turnaround by recently rigging a digital camera to his microscope, enabling him to e-mail data to other labs.
“It’s another tool. My concern is, if I have the capability to see something under the scope and can verify it, I feel that much more comfortable that I’m getting to control of the disease a day earlier, basically,” he says, adding that it also can have a profound effect on spot management practices.
“It’s probably made me not trust the window of control of a fungicide as well,” Myers says, adding that if environmental conditions create a scenario that causes him to check a sample before the window of control expires, he’s more likely to react than to wait.
Gordon Caldwell, CGCS
Green Spring Valley Hunt Club, Lutherville, Md.
Caldwell, a longtime superintendent, still manages turfgrass a lot by his wits, and sometimes that’s not a bad thing deep in the Mid-Atlantic region where the vagaries of disease test one’s mettle.
“I came here 17 years ago out of Ohio ... thought I’d learn about diseases,” he says. “I’m still here and still learning.”
Green Spring Valley is quite the classroom. Built shortly after the turn of the 20th century, it has 100-year-old push-up greens — mostly Poa annua with a little bentgrass — and ryegrass/Poa fairways and tees, plus a smattering of other turf varieties here and there.
Caldwell and an assistant scout the course ahead of the mowers every morning. “From Memorial Day to Labor Day, we never know what we might find,” he says.
The 23-year GCSAA member has waged many a battle during long, hot and humid summers against the likes of anthracnose, gray leaf spot, Pythium, brown patch and so on. While Caldwell never knows what his scouting sojourns may turn up, it’s probably not going to be something he hasn’t seen before.
Even so, he often enlists the help of the diagnostic lab at the University of Maryland and the expertise of Extension educator and researcher Peter Dernoeden, Ph.D.
“We’ve learned not to cut back so much on nitrogen and we’ve developed other treatment protocols with Dr. Dernoeden,” Caldwell says. “His work is pretty much accepted in this area. When he comes up with a plan, it usually works.”
There is one thing Caldwell would like to suggest to academia, however.
“If I was running a turf school, I’d have everyone do an internship in the transition zone just to learn about turf diseases,” he says.
Sean O’Connor, CGCS
Forest Akers Golf Course at Michigan State University
East Lansing, Mich.
A disciple of Paul Rieke, Michigan State’s renowned professor emeritus of turfgrass management (see lead article), O’Connor has taken to heart the attributes of accurately measuring soil moisture as a hedge against turf disease and other issues.
O’Connor utilizes an electronic soil moisture meter to monitor the 90 percent Poa greens at the university’s West (the championship venue) and East courses to achieve more uniform conditions, as well as improve irrigation efficiency and to ward off potential disease problems.
The tool, a TDR 300 Soil Moisture Probe made by Spectrum Technologies in Plainfield, Ill., measures the percentage of volumetric water content in the soil and basically enables the superintendent to fine-tune his watering program.
“I’ve found that on my particular greens, if I can keep that content between 19 and 21 percent, then the greens are relatively firm in terms of being playable, but at the same time they have enough moisture to get through a normal hot summer day,” the nine-year GCSAA member says.
The probe is especially valuable in managing the greens on the West Course, which, O’Connor notes, feature a unique mix of 11 venerable push-ups and seven 15-year-old USGA greens.
O’Connor, who has been at Forest Akers since 2001, also uses the probe in problem areas on the bluegrass fairways. He says the tool is easy to use by all members of the staff. But, most important, the probe serves as an aid in the decision-making process. As he scouts greens every morning, O’Connor uses it to help determine what measures to take — hand-water or turn on the irrigation system.
“I think most superintendents pride themselves in going out and by looking at a green they can determine whether there’s moisture stress,” he says. “But this device really does tell me. There’s no guesswork.”
– T.O.
RECENT issues
 |
 |
July |
June |