Dr. Gregg Munshaw knew the history around mixing cold season grasses with warm season grasses. He knew of the attempts in California in the 1950s and heard of a University of Maryland researcher trying it again in the 1970s. Both failed.
So when Brian Winka, then a parks maintenance supervisor, approached Munshaw at a National Sports Turf Managers Association meeting to tell him about bluemuda — a blend that combines bermudagrass and bluegrass — the University of Kentucky researcher tried to brush him off.
“I thought he was crazy,” Munshaw recalled. “I thought it was just a bad idea.”
But Winka could tell Munshaw was more receptive than some of the other sports turf professionals at the conference, so he invited Munshaw to visit his athletic fields in St. Louis to see how bluemuda, the mixture of the two, was working.
Munshaw did, and as he looked at the quality of Winka’s fields even after the beating they took during the spring soccer season, Munshaw was sold. He planted his first research plots at the University of Kentucky in 2015, helping to drive forward bluemuda’s development.
And to Munshaw, as climate change continues to widen the transition zone — blurring the line of where to use cold and warm season grasses — bluemuda’s versatility can serve as the “best of both worlds.”
“We’re always going to be fighting with the climate and extreme weather events,” Munshaw said. “So what this is affording us to be able to do is have a grass that’s really strong.”
Bermudagrass excels under high heat and moderate winters, while bluegrass grows best in cooler climates. Traditionally, athletic fields will choose either a cool or warm season grass type, a tricky decision for fields located in a transition zone running across the country — from the Carolinas to southern Pennsylvania and westward.
The transition zone includes parts of California, and the Rose Bowl in Pasadena uses bluemuda.
“You’d think LA would be suitable for bermuda, but it actually struggles there as it never really gets all that hot,” Munshaw wrote in an email. “They still use it as a base for good footing, but include bluegrass for aesthetics and recovery.”
Should bermudagrass be chosen on transitional zone fields, rye grass is overseeded to help sustain the turf during the winter. For years, Winka attempted to mix ryegrass with bermudagrass permanently, eliminating the need for a groundskeeper to overseed each fall.
But when the heat of the summer arrived, the ryegrass wouldn’t survive, another casualty of the variable temperatures in the transition zone.
“The joke is about the transition zone in the United States is … ‘Where we can grow all grasses equally poor,’” said Nick McKenna, a sports field manager at Texas A&M and a member of the turf managers’ association board of directors.
“One year might be a great bermudagrass year,” McKenna said. “And you can turn around the very next year and you just get a different weather pattern.”
But what’s made bluemuda possible — and why it didn’t work in the 1950s and 1970s — is that strains of bluegrass now have been bred to make them more heat tolerant. When Winka switched to a hardier variety of bluegrass and mixed it with bermudagrass, he realized the new type allowed both grasses to survive year-round.
Winka also discovered advantages over traditional overseeding processes, finding a healthier turf that requires fewer chemicals and is more resistant to disease.
“Environmentally, we’re using less herbicides and fungicides because it’s a healthier strand of grass and a thicker strand of grass,” Munshaw said. “Environmentally, we’re onto something that’s important here. Any time we can reduce our chemical use is a big deal.”
There’s a certain peace of mind that comes from having a field with two grasses capable of sharing the stresses of each season’s extreme temperatures. Should an extremely harsh winter kill off the dormant bermudagrass, the bluegrass is still on the field. The same goes for extremely hot summers.
It’s an insurance policy of sorts, especially for high school athletic fields, to ensure a field is not completely out of commission. Winka used to work for a parks and recreation department outside of St. Louis. The worst-case scenario in the spring is to find out winter kill eviscerated the bermudagrass.
“Now we have to shut this field down and either reseed, resod or resprig,” Winka said. “By [using bluemuda], you always have something growing. So it does kind of hedge your bets a little bit.”
While bluemuda assists with a shifting climate and offers other environmental and economic benefits, some athletic programs and golf courses use it for aesthetic reasons, seeking a green turf year-round. The latest trend is bluemuda extending to people’s yards, Munshaw said.
With bluemuda, golf courses can achieve a striped fairway, a color pattern bermudagrass alone couldn’t achieve. The move to a new turf in tee boxes and fairways has proven beneficial.
“What these golf courses started finding was that they were having increased revenue, even though it’s the same old golf course,” Munshaw said. “Golf, I think, jumped on it more for the aesthetic reasons other than anything else, and it’s done really well, literally spreading across the country.”
As climate change leads to a larger transition zone, bluemuda — along with its other benefits — is finding its way into the mainstream. Dr. Peter Landschoot, a turf grass scientist at Penn State, said the university is in the planning stages of bluemuda research in a cooler climate.
And as Winka looks through sports turf magazines and websites and sees advertisements for bluegrass boasting the strain’s compatibility to mix with bermudagrass, he can’t help but laugh.
“Because this was something that not too long ago,” Winka said, “if you told somebody that this is what you’re going to do, they would kind of laugh at you.”