Salt Compositions and Irrigation Levels Affect Creeping Bentgrass Quality and Soil Characteristics in Four Rootzone Media.

Salinity reduces turfgrass quality and alters soil characteristics. Multiple factors influence salt stress severity. The objective of this experiment was to evaluate the influence of salt composition, irrigation level, and soil type on salinity damage. ‘Seaside II' creeping bentgrass (Agrostis stolonifera) was seeded in four rootzone media, clay, loamy clay, and USGA and California style mixtures. Creeping bentgrass was exposed to five salt compositions: no salt (control) and electrical conductivity (EC) at 10 dS m^-1 with sodium absorption ratios (SAR) of 2.5, 5.0, 15, and infinity, at four irrigation levels of 60, 80, 100, and 120% of evapotranspiration (ET). Highest tissue dry weight and visual quality were observed in creeping bentgrass grown on clay and loamy clay soil with no salt exposure. Irrigation levels had limited influence on turfgrass quality and growth in this experiment. Loamy clay soil had the highest soil EC, followed by clay soil > USGA = California style mixtures, while clay soil had the highest soil pH. The lowest soil EC and the highest soil pH were observed in the control treatment (no salt). Soil EC increased along with the irrigation levels. However, soil pH was not affected by the ET. Saturated water conductivity decreased as the SAR increased. Water conductivity of sand rootzones was least affected by salt compositions compared to loamy clay and clay soil. Water conductivity of loamy clay with high organic matter (OM) was less affected by salinity than clay soil with less OM. Interactions between salt composition, irrigation level, and soil type were observed.