Photo by Mark Hansen
NU graduate student Anne Rist uses the "green speed" measuring device on a Lincoln gold course. She developed the device as part of her master's degree. The equipment is designed to provide turf specialists with fast and consistent indications of how grass affects a golf ball's deceleration.
| Uniform putting greens the goalGolfers who strive to putt a small white ball successfully through grass greens soon may have one less factor to blame for an errant putt because of work by an NU graduate student.Putting greens, the site of about half a golfer’s strokes, comprise less than 3 percent of a golf course’s total area. Yet they’re responsible for 60 percent to 70 percent of all chemical and fertilizer costs, and 10 percent of mowing time. That makes greens management important. All putting greens are not created equal and all are not maintained equally well. But one characteristic all greens should have is smooth, uniform putting surfaces. As part of her master’s degree project in horticulture, Anne Rist developed a timing device designed to help measure putting greens’ uniformity. IANR researchers in biological systems engineering, biometry and horticulture worked with her on the device designed to accurately measure a golf ball’s deceleration. Previously greens’ uniformity was measured by the Stimpmeter, a 36-inch long bar that releases a golf ball at a predetermined angle. The distance the ball rolls in two opposing directions is measured. That number is called “green speed,” a term commonly heard during golf tournaments. “Most people, when they hear green speed, that’s what a Stimpmeter measures,” Rist said. “It’s actually the distance a ball rolls across a green. It’s really not speed, it’s just a distance.” The Stimpmeter only looks at the final ball roll distance, and doesn’t make evident such surface problems as a thin stand of grass, weeds or diseased turf. Rist's timing device measures true green speed — how quickly a surface slows down a golf ball. The machine, called the Ristometer, uses a Stimpmeter to release a golf ball through a series of electric eyes housed in a 6-foot long plastic tube, cut in half lengthwise. As the ball travels through the tube it breaks beams created by the electric eyes. Each time this happens, time and distance data are collected by a small on-board computer. They’re later converted to deceleration rates. Designed for turf specialists, the Ristometer will be used to determine which management practices — such as fertilizer application rates and grooming frequencies — or turf cultivars provide the most uniform putting surface, Rist said. “Using this device, we as researchers can help golf course superintendents make educated decisions on what to do to produce smoother putting conditions for their golf course greens,” Rist said. — Dan Holder |