Effects of wastewater sludge topdressing on color, quality, and clipping yield of a turfgrass mixture

Abstract

The objectives of the present study were to determine the effects of the rate and timing of the application of sun-dried wastewater sludge from a food processing company's wastewater system on turfgrass growth and quality. The results were compared with those obtained with ammonium nitrate, and changes in the concentration of heavy metals and the presence of fecal coliform in turf soils after sun-dried wastewater sludge application were determined. The rate and the timing of sun-dried wastewater sludge and ammonium nitrate applications affected the turf color, quality, and clipping yield. Monthly fertilization resulted in a more uniform color and turf quality than infrequent spring and fall fertilization. Compared with the background values of base soils, heavy metals did not accumulate in sun-dried wastewater sludge-amended soils over the test period. Fecal coliform was not detected in sludge-amended soil samples, indicating that bacteria regrowth did not occur during the study period.