Evaluation of individual and combined management practices to reduce the off-site transport of pesticides from golf course turf

The detection of pesticides, associated with turfgrass management, in storm runoff and surface waters of urban watersheds has raised concerns regarding their source, potential environmental effects and a need for strategies to reduce their inputs. In previous research we discovered that hollow tine core cultivation (HTCC) was more effective than other management practices for reducing the off-site transport of pesticides with runoff from creeping bentgrass turf managed as a golf course fairway. This was primarily the result of enhanced infiltration and reduced runoff volumes associated with turf managed with hollow tines. In this study we evaluated the addition of verticutting (VC) to HTCC (HTCC + VC) in an attempt to further enhance infiltration and mitigate the off-site transport of pesticides with runoff from managed turf. Overall, greater or equal quantities of pesticides were transported with runoff from plots managed with HTCC + VC compared to HTCC or VC alone. For the pesticides evaluated HTCC < VC < HTCC + VC for the off-site transport of the high mobility pesticides while HTCC = VC = HTCC + VC for the low mobility pesticides. It is likely the addition of VC following HTCC further increased compaction and reduced availability of recently exposed soil sorptive sites produced from the HTCC. Results of this research provides guidance to golf course managers on selection of management practices that assure quality turf while minimizing off-site transport of pesticides, improving pesticide efficacy and the environmental stewardship of managed biological systems.