SportsTurf

IRRIGATION & DRAINAGE 28 SportsTurf | April 2016 www.sportsturfonline.com FIELD SCIENCE W hen the old turf was stripped off of the baseball field late last year to make way for new bluegrass sod at Canal Park, home of the Akron RubberDucks (AA Affiliate team of MLB's Cleveland Indians) in Akron, OH Chris Walsh was surprised by what he found — high clay content contaminated in the soil profile. A veteran of five seasons with the RubberDucks as head groundskeeper, Walsh says he's sure compaction on his field "would have been a lot worse" if he hadn't taken preventative measures these past 5 years to alleviate and prevent compaction. "Soils that have a higher clay content are more prone to soil compaction than sandy soils. This is the basis for constructing athletic fields on sand-based soil profiles compared to native soils that contain clay," says Gerald Henry, PhD, Associate Professor of Environmental Turfgrass Science, Athletic Association Endowed Professor at the University of Georgia. "Soil compaction occurs in response to excessive amounts of traffic on athletic field surfaces. The structural integrity of the soil may be compromised, causing a reduction in pore space normally available for water and oxygen," Henry says. Compaction may also be caused by an imbalance of soil chemistry, resulting in a decreased soil structure, says Kevin Karnei, geologist with Performance Nutrition, a company that produces fertilizers, fertilizer additives and soil amend- ments. Karnei explains an imbalance in soil chemistry this way: "Not having enough calcium, magnesium and other ions that would normally keep the clay 'flocculated' or spread apart and open so they can receive air, nutrients and water through the pore spaces. A proper balance allows for air and water to move through the soil. An improper balance doesn't." "What you have when you have decreased soil structure is you have collapsed clays that are stacking on top of one another, especially where there's not good water infiltration, or the soil conditions are not perfect, or BY STACIE ZINN ROBERTS the water conditions are sub-standard," Karnei says. Compacted soils may cause a myriad of issues on sports fields. "Compaction causes the soil to lose pliability and the potential to absorb impact. The resulting surface hardness may increase the risk for lower extremity injuries and concussions. Furthermore, surface hardness can greatly reduce field playability, thus impacting aspects of the game such as ball roll, bounce, and speed. Compaction can also reduce root elongation within the soil profile. Athletic fields with shallow root systems have a higher probability of being uprooted during use. This may also increase lower extremity injuries that are associated with traction," Henry says. Karnei says signs of sports field compaction include: "decreased water infiltration that results in puddling, shallow roots, decreased vigor and health of the plant, decreased grass health in color, thickness and turgidity, and the ground actually feels harder." Chemical and mechanical methods of relieving and preventing soil compaction are available for use on sports fields. Because Canal Park hosts not just baseball games, but movie nights and other community events, Walsh has a nearly continual parade of foot traffic on his sports field. Since he started at the RubberDucks, Walsh has added KaPre ExAlt to every tank mix he's sprayed on his field. KaPre ExAlt is a blend of concentrated fulvic acid, polyelectrolytes and naturally derived plant-based surfactants from Performance Nutrition. The product is designed to correct compacted soils by solubilizing minerals in the soil to increase porosity, restore balance in the soil, and increase movement of air and water. It can be applied in a tank mix, or through fertigation. Walsh says he uses the product to prevent compaction, reduce crusting, but also to help grass seed germina- tion. High traffic areas at short stop, second base and in front of the pitchers mound require frequent applications of overseed. He says BREAKING UP IS HARD TO DO: WHY IT'S IMPORTANT TO DECOMPACT YOUR FIELDS "Soils that have a higher clay content are more prone to soil compaction than sandy soils." — Gerald Henry, PhD Group photo of research team, L to R: Chase Straw, PhD candidate; Rebecca Grubbs, PhD candidate; Kevin Tucker, research associate; and Gerald Henry, PhD.

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