Reducing Salinity Parameters with Cultivation Practices and Products on Golf Course Fairways.

As continuous drought and increased temperature have prevailed in the southwestern US, the quality of groundwater has been decreasing as discharge rates exceed recharge rates. Drought conditions and poor irrigation water facilitate the accumulation of salts in the effective rootzone of bermudagrass fairways. Golf course superintendents in this region are concerned about poor soil and turfgrass performance resulting from high salinity levels. Therefore, the objective of this study was to determine if selected commercial products with and without cultivation practices could effectively reduce salinity levels with normal irrigation. The study was conducted at the Rawls Golf Course and Meadowbrook Golf Club in Lubbock, TX. Cultivation practices were applied in mid-June 2015 as a strip treatment with tractor-mounted hollow-tine aerifier, Aerway slicer, or untreated followed by initial product applications. Salinity parameters (EC, ESP, and SAR) were determined from soil sampling in June, August, and October 2015. Visual turf quality, digital image analysis, NDVI, and volumetric water content (VWC) were obtained every two weeks. Few statistically significant differences were observed above ground. The majority of statistical differences occurred following the application of cultivation practices with hollow-tine aerification resulting in poor quality for four to six weeks. This resulted in lower turf quality, NDVI, and green cover. The hollow-tine treated areas exhibited lower VWC throughout the summer. There were also significant differences in VWC on July 28 with the water penetrant products maintaining higher water content two weeks after application. This result may demonstrate greater water movement into the soil to help diminish salinity stress near the soil surface. Laboratory procedures on the soil and irrigation water may provide clearer results on the true effectiveness of the products and combination treatments. The area received record rainfall during the spring and summer that likely leached any salt accumulation at either site; however, very limited rainfall in July and August placed a much greater reliance on the irrigation system at both locations. Hopefully the increased use of irrigation water will result in variable salt accumulation among the treatments to help demonstrate the most effective treatment or combination of treatments.