Verticutting, also known as dethatching, was a victim of budget cuts and personnel losses over the past few years, according to Glenn Musser, president of TurfTime Equipment in New Holland, PA. “If a manager had to choose between aeration or dethatching the manager would most often choose aeration,” Musser said. “Many fields were able to survive a few years without dethatching without seeing significant turf problems. However within the past 2 years those fields were starting to see fungus and insect damage. The accumulated thatch layer prolongs highly humid conditions, which favors diseases. The neglected thatch layer will also cause the grass to develop a shallow root system which makes it less able to survive tough conditions, especially in the heat of summer.”
Musser said now he’s seeing some sports field managers adding back dethatching as part of their management practices. “They realize that aeration without dethatching is not the Best Management Practice. To control diseases and push the turf roots downward, dethatching is a valuable part of the schedule.”
We exchanged emails with James Bergdoll, CSFM, the turf manager and maintenance superintendent for Elizabethtown Sports Park in Elizabethtown, KY on his verticutting practices. Why is he now verticutting? “We like to lightly verticut our bermudagrass fields at the beginning of the growing season to stimulate lateral and vertical growth and remove any dead material that could be matted into the canopy,” he emailed. “In the growing season, a deeper cut removes more material to allow moisture and oxygen to reach the rootzone more easily as well as control thatch. We also like to verticut following core aerification to help break up the cores and redistribute that material into the soil profile. Verticutting can also aid with overseeding by opening the canopy giving ryegrass a place to make soil to seed contact. Adversely, verticutting aids in the transition by removing ryegrass and stimulating bermudagrass growth.”
Another verticutter is Darian Daily, the sports field manager for the Cincinnati Bengals. “We verticut our fields to promote lateral growth of our bermudagrass, help control thatch and organic build up, and to help ‘wake up’ the bermuda as is comes out of dormancy, by opening up the canopy to allow sunlight and heat down to the ground,” Daily said.
Bergdoll: “In the past we verticut only one or two times a season but we are planning to increase to hopefully three or four times a season. I have found that we need to be more aggressive with the bermuda to keep it stimulated and give it room to grow. We actually had an issue last summer where the bermuda was growing almost too aggressively and the runners were growing on top of the canopy.”
Daily: “We verticut three or four times a year depending on field use. Most of the time it is in the spring and early summer because I have found the Patriot bermudagrass in my area doesn’t respond well once the temps get above 90°. We use 1 mm blades in our verticutting because they don’t damage the bermuda as bad as the 2 mm blades did. We used the 2mm blades when we had cool season with success, but the 2 mm seemed, I felt, too aggressive for the warm season grass and took more time to heal.”
We asked Bergdoll and Daily for any tips for others to get best results when verticutting. “Watch your timing; obviously you want to verticut when the turf is actively growing due to the aggressive nature of verticutting. Verticutting too late in the season can weaken the turf going into dormancy potentially making it more susceptible to winter kill. Periods of heavy field use may warrant not verticutting as planned so be flexible as with any cultural practice,” Bergdoll wrote. “On native soils, irrigate the field before verticutting to soften the soil allowing the blades to cut into the soil easier. The material that is removed from verticutting can be used to sprig bare or thin areas.”
Daily said, “Don’t be afraid to do it. The first time I verticut, I thought I had killed the plant with all the thatch and vegetation that was pulled up. Two weeks later the plants were in incredible shape, growing vigorously and healthy. Also, try and get down into the thatch layer at least once to help control the organic matter the natural grass produces.”
“The other significant increase we have seen over the past year is in the number of Thatch Master verticutters coming back into service. Units that have been sitting idle for years are being pulled out and overhauled. For a fraction of the cost of a new unit the sports field manager can install a new blade assembly and drive line, updating the older Thatch Master to the standards of new models,” Musser said.