Use Of Adjuvants In Irrigated Alfalfa Production On Saline Sodic Soils.

Irrigation in semi-arid environments is frequently practiced with poor quality water including water that contains sodium and other salts leading to salt accumulation in the soil profile.  Salt accumulation in the rooting profile can reduce yield, alter soil structure, and at elevated levels damage and kill crops.  Agronomic  recommendations for preventing salt accumulation in the soil profile include applying additional irrigation water to leach salts from the root zone.  Several products, including adjuvants are marketed to agricultural producers with the claim of facilitating salt leaching and conserving or improving soil structure.  One commercial product containing 48 percent Ammonium Laureth Sulfate, was broadcast applied with 112 L ha ^-1 (12 gal ac ^-1) water at a rate of 0.73 L ha ^-1 (10 fl oz ac ^-1), between alfalfa cuttings to an established alfalfa (Medicago sativa) stand near Pecos, TX during the 2012 growing season.  The soil series was a Balmorhea Silty Clay Loam, calcareous, moderately alkaline, with the particular field being both saline and sodic.  Alfalfa forage yield of treated and untreated  replicated plots was measured for two cuttings with no significant difference  observed.  Pre and post treatment soil tests were also conducted to monitor soil salinity changes with no significant differences observed between treated and the untreated checks.