Keeping Turfgrass "Green"
By Jane Scully
The Park Authority’s mission of promoting stewardship of our natural resources reaches all aspects of our operations. Of particular interest has been our golf course and athletic field turf management. Keeping the athletic fields safe and playable is a major responsibility of the Park Operations Division. How can this be managed without using — or overusing — pesticides and fertilizers that may be washed into nearby streams and waterways, affecting plant and animal life? Are these missions contradictory?
Bob Studholme, the Fairfax County Park Authority’s Turfgrass Specialist, believes that athletic fields and golf courses are not villains at all. In fact, fertilizers are not the largest part of his turfgrass management program. The issue, he says, goes much deeper than that—down to the soil, the medium in which the turfgrass grows.
”Lots of managers manage for the grass when you should be managing for the soil. If you can do that, keep the soil chemically balanced, biologically active and well drained, your need for fertilizer and pesticides will be much lower.”
Since Studholme is responsible for the care and feeding of 295 athletic fields covering 280 acres in the county, his methods have a direct effect on soil — and stream — health. Before taking this position, he spent 17 years managing the Park Authority’s golf courses. When Studholme implemented his soil-based turf management program at the Burke Lake Park golf course, annual fertilizer requirements dropped by two-thirds. And with healthier soil and turf, water and fungicide use was reduced by 50 percent.
But there are any number of factors to study before fertilizer is even considered. Studholme takes soil samples from each of his 295 athletic fields every two years to determine their chemical deficiencies and sufficiencies. Such laboratory analysis is critical in achieving chemical balance of the many elements. Most soils in our area are low in calcium and potassium, while being too high in magnesium.
Equally important, Studholme tells us, is to make sure the soil is properly aerated. This is done for each field twice a year.
“If there’s no air, there’s no biology. Soil microbes, like bacteria and other organisms, need oxygen to proliferate. They are the key to breaking down materials you add to the soil to make them available as food for the plant.”
Only after the soil in each area is tested, balanced and aerated is fertilizing done. Studholme uses natural organic fertilizers as much as he can, feeding the soil at least twice a year with fully composted poultry litter blended with kelp, dry humates, molasses and rock minerals. These nutrients feed the plants as well as help balance the chemistry, depending on amounts, type and source. The soil microbes use the carbon sources for energy.
Ironically there are two major factors in the Fairfax County area that work against getting air into the soil. The area’s prevailing soil type is an easily compactable sand-silt clay mix. The soil is too high in magnesium and too low in calcium and potassium, making for “tight” soils that do not breathe well and are rock-hard when dry, goopy when wet.
As well, our climate doesn’t help much. Studholme notes that we live in the Transition Zone between where cool-season grasses are stressed throughout our typical summers and the warm grasses go dormant, or may not even survive, our winters.
The other main challenge to maintaining turf grass is the very purpose of the fields — use for athletics. The cleats of soccer, baseball, softball, football and lacrosse players run on the fields most hours of every day, inevitably compacting the soil and driving air out of the soil.
Despite the challenges, Studholme aims to keep all the county fields safe and playable, with healthy turf on top. And in fact, the fields are in much better shape than they were several years ago. The management program builds in the vagaries of weather and season. “Every year is different,” says Studholme. “You can’t just go by the calendar.”
Studholme should know. He practices at home what he does in his turf management program. And with “minimum effort,” he’s got the best lawn for blocks around.