Impact of Choosing the Right Soil Test: Lessons Learned in Saline and Sodic Environments.

New Mexico soil test results over a 5 year period identified 15-20 percent of the soils as being saline and 10-20 percent as being sodium affected. NMSU used the saturated paste method for determining salinity. Analyses from private laboratories using 1:1 extracts showed a disparity in the classification and recommendations for reclaiming saline and/or sodic soils. Mathematical adjustments could be made for saline soils to estimate saturated paste salinity from 1:1 extracts. However, no relationships could be determined between 1:1 and saturated paste extract SAR. This has led to under-estimation of both the quantity of water and amendment application rate to effectively manage the saline or sodium affected soils. Demonstrations for grower meetings and publications are being used to raise client awareness and knowledge of a potentially yield limiting problem. Knowledge of salinity assists in the correct crop or variety choice as well as an assessment of the required amount of water for an acceptable yield. Extension agents and consultants will play a vital role in identifying salinity and as such should be equipped to recommend the best soil test possible for basing management decisions.