Groundwater Contamination Potential of Pesticides and Fertilizers Used on Golf Courses

Leaching losses from seven pesticides applied to 1.2 m deep soil monolith lysimeters with a turf cover were negligible while applications of phosphorus (P) to turf indicated that soil levels of P can increase rapidly after only one to two years of annual applications. Lysimeter percolate was continuously monitored and only one of seven pesticides were detected during the 2.5 y monitoring period. Triadimefon was detected at a concentration of 31 μg L^-1 55 days following application with subsequent detections at 10 μg L^-1 or less. Phosphorus applications of 200 kg ha^-1 to a P-deficient turf growing on a sandy soil increased soil P test values in the 0-7.5 cm soil layer from 3 mg kg^-1 to 9.6 mg kg^-1 in 1992. Soil P rose to 25.3 mg kg^-1 in 1993 despite applying only 50 kg ha^-1 in 1993.