Managing Soil Salinity
For the past 30-years or so, some parts of the country have been in a perpetual wet cycle, which has brought on high salinity levels in the soil. Salts move with water and when the water evaporates, the salts don’t, and they accumulate over time. In general, if the soil is white and nothing’s growing, you have a problem.
Chris Augustin is an Extension soil health specialist at North Dakota State University. He says the key to salinity management is water management, and practices that encourage leaching and drying the soil profile.
"That would include cover crops after your cash crop harvest, so your small grains or something you’d harvest in August. We still have a big window of water use that we can use, and those late-season cover crops can help dry that soil down," he says. "You want it dry going into the winter, so then the next spring when we have our snow melt, that’s when most of the leaching occurs, and also evaporation is low. Evaporation’s kind of that conveyor belt that brings salts to the surface."
Salt raises electrical conductance in the soil. Testing the level of conductance can indicate which species of crops or forages you should plant based on their salt tolerance.
"Some of our more sensitive crops would be corn, soybeans, chickpeas, any sort of those pulses or legumes are pretty salt-sensitive. And then our more salt-tolerant crops would include wheat, sunflowers, canola, and barley is one of the most salt-tolerant cash crops that we grow," says Augustin. " And so, crop selection can definitely help in at least getting something growing there."
Augustin says with the right management, a salinity problem can be remedied in about three-to-five-years.