On Yale’s athletic campus, an unassuming training field has become a testbed for a more sustainable way to maintain grass.
The experiment involves a method of turf management known as fraze mowing, in which a specialized machine strips the surface of unwanted weeds and thatch so it can be reseeded with new grass types that are more drought-tolerant and require less herbicide.
The field in question is known as “C-Special,” which sits just down the block from Reese Stadium. Leading the experiment are Jim Terenzio, superintendent for landscape and athletic grounds in the Office of Facilities, and Danielle Upham, senior associate athletic director for facilities and operations.
Fraze mowing has been common in Europe for decades but it is still relatively rare in the U.S. If the method proves viable for Yale, it could give the university an additional tool for maintaining athletic fields in support of its broader sustainability goals.
‘The field held up unbelievably well’
The project started in May 2024 with the first phase of mowing, performed by a specialized contractor. After the field was stripped, aerated, and reseeded, it spent the summer dormant to allow the new grass seed to take root.
Play resumed in fall 2024——two weeks ahead of schedule. Historically, C-Special had mostly been used by club and intramural teams. But with the improvement of the turf quality as a result of the fraze mowing, Athletics has seen an uptick in use by varsity programs.
“Lacrosse, in particular, can be very hard on grass but the field held up unbelievably well,” Terenzio says. “The new cultivars of bluegrass are much more wear tolerant and while we had some irrigation going, it was nothing like what we would ordinarily do.”
Benefits for ecosystems and athletes
The benefits of fraze mowing—to athletes and the environment—are many.
“By taking off the top layer, you leave behind the grass you want,” explains Terenzio. “In place of the unwanted weeds and thatch, we’re planting 100% bluegrass seed, which requires less water, less nutrients, and is also more wear tolerant.”
To date, the field has used 20% less nitrogen than before the fraze mowing. Watering is taking place every four days instead of every two days, and the need for pesticides has been significantly reduced, Terenzio says.
For athletes, a field maintained in this way can reduce injuries by creating a more stable playing surface. By eliminating shallow-rooted grasses and weeds that destabilize turf—and reseeding with deeper-rooted varieties —the grass is less likely to have an uneven playing surface that gives way under a running athlete, which is when injuries can occur.
With the seeming success of C-Special, Terenzio is eager to explore whether fraze mowing can be utilized elsewhere at Yale.
“This was approved a pilot project to see if it was possible for us to do this,” says Terenzio. “I believe it worked very well and I hope that we continue to do this in the future.”