We all have them or have seen them — the areas where crop productivity falls near null, and foxtail barley encroachment begins. Areas affected by high salinity are often referred to as alkali sloughs, and are considered for remediation.
Years of no- or minimum-till farming across the prairies has certainly helped the situation, says Kelly Farden, irrigation agrologist with the Saskatchewan Ministry of Agriculture. Continuous cropping draws moisture through the plant instead of to the surface, leaving salts to accumulate in areas below ground. When soil is bare, it is exposed to the heat of the sun, and in areas with high evaporation and low precipitation, this can spell trouble for high water tables, where salts and water move through the soil, towards the surface through capillary action. In these cases, salts accumulate right on the surface of the soil, making it difficult, if not impossible for plants with low salt tolerance to survive.
In this video, Farden explains how soil salinity can be assessed, including a brief description on how the government assesses a given chunk of land for its suitability to irrigation. Farden also explains what can be done to manage these soils, encouraging producers to consider a forage mixture in these areas that includes plants with high water use, and those with a high tolerance to salinity. Besides the increased likelihood of one day returning to farming, one may also consider custom grazing areas with perennial forages, or simply allowing them to thrive and thereby providing a diverse habitat for beneficial insects to overwinter and find sources of nectar.