(Editor’s Note: This year, BASF and GCI are working together to tell the story of how a new active ingredient is coming to life for the golf market. The idea is to help you learn the scope of the R&D, testing, investment and plain hard work that goes on behind the scenes of product development. The formulations reached the golf market earlier this year. This is part 4 of a 4-part series on the remarkable process of bringing new chemistry to your golf course.)

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After years of preparation and testing, and no small amount of anticipation, superintendents are now able to make Revysol a part of their fungicide regimens.

Developed by BASF, the active ingredient mefentrifluconazole may now be used in the field, either as a standalone (brand name: Maxtima® fungicide) or in a compound with Insignia® (brand name: Navicon® Intrinsic® brand fungicide).

Whether as a standalone or as part of a compound, superintendents are eagerly anticipating having another weapon in their arsenal in their ongoing battle against dollar spot.

Scott Bosetti is the superintendent at White Beeches Golf and Country Club in Haworth, N.J. The 18-hole private facility is located 20 miles northwest of midtown Manhattan.

Bosetti started working on golf courses a quarter century ago. He’s spent 18 years as a superintendent, 13 of them at White Beeches where he has been regularly plagued by dollar spot issues — issues that have become more problematic in recent seasons because of wet, humid weather. He seized on the opportunity to try Maxtima when it became available this summer.

“The ability to throw a DMI chemistry out in the middle of the summer was very appealing,” Bosetti says. “Once the heart of the year gets to us, we’re kind of handcuffed. There is a just a certain amount of different types of products/chemistries that we can use, so being able to throw a new chemistry out there in the middle of the summer was something that really interested me.”

Bosetti put down an application of Maxtima in late July at a rate of 0.4 oz./1,000 square feet. When he spoke with Golf Course Industry, he had effectively received 21 days of dollar-spot control from the application.

While making the Maxtima fungicide application, Bosetti simultaneously applied Primo Maxx as a growth regulator. I’m mostly Poa annua here,” he says, “and you’re always worried about throwing a growth regulator in with a DMI, no matter what time of year it is.”

But Bosetti was assured by BASF representative Paul Ramina that the growth regulator would not cause a problem. “He told me, with all the research they’ve done, either on other golf courses, or at Rutgers, it had no effect on it.” Bosetti recalls, “so I went out with an 11-oz.-per-acre rate of Primo and got no yellowing, no nothing.”

Tim White is in charge of the turf at Prestwick Country Club in Frankfort, Ill., roughly 35 miles south of Chicago. The 18-hole private club features a Larry Packard-designed golf course that was completed in 1964.

When White arrived at the club in 2005, he found himself facing dollar-spot issues that were exacerbated by resistance issues related to DMI-based chemistries that were used by his predecessor to the point where White was getting no more than 10 days of control per dollar spot application (White is quick to point out that those chemistries were state-of-the-art at the time his predecessor applied them).

White found that Emerald was effective against dollar spot; at one point, he was getting 40-plus days of control. Fifteen years later, he embraced the opportunity to have history repeat itself, this time with Maxtima fungicide. “I just thought the product sounded interesting,” he says. “I saw some of the research numbers online and our sales professional (Andy Morris) got us a trial sample.”

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On Aug. 6, White applied Maxtima on one of his fairways. “We picked a hole that we knew had previous issues with dollar spot,” he says. “We also picked this hole because it has a fair amount of Poa trivialis in the fairway, especially on some of the fairway edges.”

The fairway in question also had summer-patch issues. Within six days, though, the dollar spot on the trial fairway was gone — and within a week, the summer patch was all but gone, White says. Twenty-one days later, the summer patch had not returned, he adds.

Two Michigan-based superintendents are hoping to achieve similar results with Maxtima fungicide that Bosetti and White have attained.

Jeff Holmes is the longtime director of agronomy at Egypt Valley Country Club, a private facility in Ada, an eastern suburb of Grand Rapids. He’s been at the club for 25 years and has worked in the turf industry for 34. He spoke with Golf Course Industry the same week he put down an application of Maxtima.

Holmes decided to try the product based on past success with DMI-based chemistries and his ongoing relationship with BASF. “They usually deliver good products,” he says, “and the price point value is very favorable for just fighting against dollar spot and not worrying about other diseases.”

Holmes had bigger problems with dollar spot in 2018 than he did this season. He believes the weather was a factor, noting that in recent seasons he has found himself applying fungicide more frequently than in years past. Ideally, he’d like to apply a fungicide on a monthly basis, but circumstances don’t always allow for that.

“I think our durations are shorter,” he says, “but it’s really hard (to determine) unless you have a checkplot and are going year to year. Sometimes, a certain product will work one year and the next year it doesn’t work quite as well, so I really think a lot of it is weather-driven, but I do feel that the durations are a little shorter than what they were.

“We’ve had products that have gone 28 days and longer and we’ve had products that have lasted eight days, and sometimes that same product worked three months earlier or the year before,” he adds. “That’s why I say sometimes it’s just the climate and the conditions and not knowing if the pathogen is already in the plant and how we’re affecting it. There are a lot of variables.”

Tom Schall has worked in the turf industry for more than three decades. Today, he’s in charge of the turf at the Oakland University Golf and Learning Center in Rochester, Mich. The center features two 18-hole courses plus a state-of-the-art practice area.

When Golf Course Industry spoke with Schall, he was preparing to apply Maxtima for the first time; the application was tentatively scheduled for the end of August. He is hoping that Maxtima will prove an effective remedy for the dollar spot issues that have plagued him in recent seasons “I’m not getting the length of control that we were used to,” he says. “Two weeks is almost unheard of anymore.”

Schall says early season rains exacerbated the dollar spot issues he’s been dealing with this summer. “Normally, what we do is put an application down for dollar spot earlier in the spring as a (preventative measure),” he says, “and we just didn’t have that availability to do that this year with the rain. I think that’s one of the reasons we’re having this problem.”

Apart from its effectiveness against dollar spot and other diseases, early indications are that Maxtima fungicide offers financial benefits. Bosetti estimates that his 21 days of dollar spot control cost him approximately $100 per acre. And longer intervals between applications allow superintendents to devote labor to other tasks. “(Maxtima fungicide) is going to allow us to move people to do other things in the fall,” Schall says, “and not have to put so much time into making a fungicide application. We’ve got a couple of renovation projects going on too. Whenever you’re doing a project, things come up and you have to move people around, so it’s going to help us be able to do that.”

White is already thinking about 2020 and how he’ll integrate Maxtima into his fungicide protocol. He anticipates making an application somewhere around May 1.

“We’re going to give it a whirl for sure on our tees next year,” he says. “We’re going to do an early season app for dollar spot reduction, summer patch and take all patch. I’m assuming on our tees we should get at least a month out of that, maybe longer, for dollar spot. We’ll probably do a fall clean-up on the tees also for dollar spot.”

White is also planning to try Navicon Intrinsic on greens.

“Historically, we get a couple applications during the summer months of an Insignia product,” he says. “Whether it’s Lexicon, or Honor, or Insignia, there are plant-health based benefits, there’s no doubt about it.”

White believes that utilizing Insignia has contributed to making his turf more stress resistant.

“When you make an application prior to a stretch of (90-degree days) that roll in and sticky nights, we just noticed that the grass responds better than it does when we’re not using the products,” he says. “We’re using less water, there’s less stress, the plant seems to have an ability to just handle the stress much better … the plant just seems to be a little bit tougher, a little bit stronger.

“I don’t have numbers to back that up, but based on previous years when we didn’t use any of it versus years when we have, it just seems like the plant can go through those periods of warm, humid days and sticky nights with less decline.”

White believes that dollar spot is becoming less of an issue than previous years because of the introduction of new products. But it’s safe to say that it will always be a concern for turf professionals. With Maxtima fungicide and Navicon Intrinsic brand fungicide now available, they have two new tools at their disposal.

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