Accumulation and Potential Remediation of Copper in Golf Course Putting Greens

The objective of this study was to determine the potential accumulation of copper (Cu) within a USGA golf green profile and analyze potential remediation techniques of soils containing toxic Cu concentrations. Accumulation study utilized: copper phthalocyanine pigment (Par), copper hydroxide (Junction DF), varying concentrations of copper sulfate (CuSO4) within irrigation, and combinations of each. Products were applied over 13 weeks at Clemson University horticulture greenhouses with samples taken at thatch depth, 0-5.1 cm below thatch, and 5.1-10.2 cm below thatch at conclusion of study. Average Cu concentrations in thatch layer was 634.7 kg Cu ha-1, with 0 - 5.1 cm and 5.1 - 10.2 cm depth concentrations of 11.26 and 6.84 kg Cu ha-1, respectively. Remediation studies exposed 5 mg Cecil sandy loam to 15 ml 1000 ppm of CuSo4-Cu followed by 4 sequential 20 ml filtration cycles of 1 N ammonium sulfate, 1 N calcium nitrate, 1 N gypsum, or water. Single filtration of ammonium sulfate removed similar or greater amount of Cu than cumulative impact of 4 filtrations of any other products with 2064 mg Cu kg-1. Studies suggest that the management or removal of thatch may alleviate toxic accumulation of copper, however the use of ammonium sulfate in irrigation water may provide additional remediation options to turfgrass managers.