Golf Course Turfgrass with Scott DeBolt

To many of us, even within the golf industry the varieties of turfgrass are somewhat of a mystery. We know that Bentgrasses are used in cooler climates and Bermudas in warmer regions and some of the playing characteristics of each but with water becoming ever more precious and golf course maintenance costs rising, I sought to get a crash course on turf types from Scott DeBolt of DLF. DLF’s popular Seed Research of Oregon products are found on numerous golf courses in the US and around the world. I had the chance to pose some questions to Scott about a variety of turfgrass issues.

I often see Scott’s posts on new varieties of Bentgrass being installed on golf courses. When I asked about how they perform better he said: The newer versions of Bentgrass offer many improved characteristics in bentgrass breeding than in years past, such as excellent disease resistance across the board lowering fungicide usage to as much as 70% reduction. Finer texture and uniformity for use on Greens, tees, and fairways (is achieved) without thatch issues. I also asked about the use of Bermuda, Zoysia and other drought resistant varieties in more northern regions. DeBolt indicated that the transition zone began some conversion around 2010 changing from bentgrass to Bermuda. He acknowledged that warm season grasses require less water at times during the year but suggested the difference wasn’t that significant.

DeBolt’s company promotes the “SuperBents” program for bentgrass varieties requiring less input, defined as an advanced generation, highly refined bentgrass variety, bred for genetically enhanced disease resistance and scientifically designed for use on closely maintained golf greens, fairways and tees. This program includes the following bentgrass varieties:

  • 007XL
  • 777
  • 007
  • MacDonald
  • MacKenzie
  • Flagstick
  • Tillinghast (new in 2023)

While in some cases the water issue can be resolved through the use of effluent that some communities need to get rid of, there are issues with salt and other contaminants that need to be considered. One place to learn more is the A-List, which identifies many of the tall fescues, Kentucky Bluegrasses, Fine Fescues and Ryegrass varieties.

When I asked about the cost/benefit relationship of converting DeBolt shared that Cool season grasses (older varieties) struggle through the dog days of summer (July-end of August) in which they may require syringing but after that a normal water cycle is sufficient. Surprisingly, he indicated that Bermuda needs water in the winter as well, saying: “You do not want dried out greens in dormant stage during long cold spells that the greens will be covered or you will have winter desiccation. So its not like you just turn the irrigation system off when first frost arrives.” He feels that bentgrasses were overwatered in the past but with new technology (moisture meters) and excellence in breeding programs today’s bentgrass cultivars require less inputs than ever before.

Obviously, the cost of conversion is a big consideration. Not only would a course seek lower ongoing maintenance costs, but also looks at the payback period of the investment. First, I asked about the time necessary for conversion which DeBolt estimates conversions from “kill to play” taking between 8 and 10 weeks. For green conversions, he said that: “Typically golf courses have roughly 3-4 acres of greens. Converting bentgrass to Bermuda would require killing out the existing greens and sprigging or sodding (I am using sprigs in this example) will be roughly $125,000-$150,000. Converting to bentgrass (seeded) will require the same killing of the existing stand and will be roughly $30,000-$40,000 for the same square footage.” Tees and fairways would cost less because there’s no need to fumigate the entire surface, as with greens.

Given the conflicting issues of water supply, consumer desire for green grass and firm, fast playing surfaces, I asked DeBolt his thoughts on these conflicting interests. First, he stated that “Brown is the new green. I think the consumer wants to play on green grass. But I do think that firm and fast with less inputs is where we are headed. However, when the golfing public turns on the TV they see lush green golf courses (camera lens manipulated) and wonder why their course doesn’t look like what they see on TV.” He went on to say that drought tolerant varieties available today are excellent selections to start with. and that one grass does not work across the board for golf courses, depending on climate ie: Bermuda will not survive in northern climates as cool season grasses will not survive in southern climates. Soil types play a big role as well as annual rainfall, high and low temps, humidity, etc all factor in when selecting the best grass to use for each location.

When evaluating a potential turf selection for a golf course, DeBolt works with the superintendent and considers a number of issues, including:

  • Water (availability, quality & cost)
  • Soils
  • Temperatures
  • Heat/Humidity
  • Cold Temperatures
  • Maintenance Budget

I asked DeBolt to share some thoughts on the different turf types. His comments follow:

  • Bentgrass are now used on greens, tees and fairways more often these days.
  • Kentucky Bluegrasses are used in many applications from low mow fairways and tees, to roughs, home lawns and commercial lawns as well as athletic fields.
  • Tall fescues are now much more drought tolerant and cold tolerant for use further north than ever before. There are low mow tall fescues that will handle ½ inch mowing heights and are now being used on fairways as well as roughs, home lawns, commercial lawns, and athletic fields.
  • Fine Fescues are used on greens, tees and fairways as well as out of play areas which are gaining additional acres as lower maintenance. They are used in shaded areas with great success.
  • Ryegrasses are more heat tolerant and have spreading capabilities with additional strengths in disease resistance. More use on athletic fields and overseeding golf courses and fields in the southern states.
  • Bermuda grass is inching further north but will struggle with the chance of WinterKill every year. Bermuda (both vegetative and seeded) can be used on athletic fields, home lawns, golf course fairway, tees, and roughs and several varieties of vegetative Bermudas are used on greens.

Lastly, I asked DeBolt to share some of the advances in turfgrass over the past 10-25 years. He said: “All species have shown improvement over this time period. Creeping bentgrasses have improved water requirements, heat tolerance, disease resistance, wear tolerance, lower nitrogen requirement, longer season of growth and fast establishment. Cultivars of Kentucky bluegrass, tall fescue, fine fescues and even perennial ryegrasses have been developed for fairway height mowing plus improved turf quality. Cool season grasses in general can be selected more easily for improvements by new cycles of breeding every few years. The ultra-dwarf bermudas are mostly closely related selections often from greens. As such they share similar problems. Oklahoma State may have a new one with unique genetics. The warm season grasses in general are vegetatively increased and take longer to determine benefits and get into production. The whole planting will be one genotype so any weakness will show up everywhere. For fairways Oklahoma State, Univ. of Georgia and UC-Riverside all have some new interesting bermudas that may work well for fairways, Some with better cold tolerance than others. New Zoysias have been developed for greens, fairways and lawns but they are much slower to establish and are less well known.

The selection of turfgrass for any golf course has long term implications. These range from seasonal differences in conditions to maintenance practices and costs and investment of capital dollars. It’s critical to make a decision that is not only cost-based but also considers market expectations and perceptions. For any golf facility, maximizing long-term economics is the goal and looking ahead to the challenges of the future should be a big part of this decision process. Guys like Scott DeBolt can help you make it an informed decision.