POTENTIAL LEACHING OF HERBICIDES APPLIED TO GOLF COURSE GREENS

A critical issue facing the turfgrass industry is the environmental fate and safety of pesticides used in the management of recreational facilities. The purpose of our research program was to develop a data base for the determination of the potential movement of pesticides from golf course greens into potable aquifers. Lysimeters were developed, m the greenhouse, for the measurement of herbicide leaching from simulated greens. Data were obtained from lysimeters containing 'Tifdwarf' bermudagmss maintained as simulated greens and receiving treatments of the dimethylamine salt of 2,4-D as a split application at rates of 0.56 + 0.56 kg ae ha-1 on a two week interval. Only minute quantities of 2,4-D were detected in the effluent from the lysimeters containing two mixtures of rooting media. These data were compared to the estimated values obtained from the GLEAMS mathematical model simulations using parameters independently determined to describe the lysimeter system The GLEAMS model overestimated the actual data-values received from the lysimeter experiments on the potential for 2,4-D to leach through both rooting-media profiles.