Soil Sodicity

Sodium affected soils are created by an imbalance of calcium, magnesium and sodium ions

This is approximately the top two feet of a sodic soil that is under CRP	This is what a sodium-affected soil looks like underground.	On the surface of this sodic soil, you can see how the aggregates have dispersed to create a crust. The dark color is organic matter that was once protected in the soil aggregates that is now “free” on the surface. Reduced infiltration is an issue in this soil.	When sodium causes dispersion, water logging can occur. This makes travel across these areas difficult and can lead to compaction from equipment.

What is the Difference between Saline and Sodic soils?

Saline and Sodic soils differ in soil chemistry and management strategies. It is important to preform correct soil analysis on your problem fields in order to properly manage and reclaim theres areas. Make sure to included soluble salt analysis and percent Sodium ( %Na ) analysis on your soil samples. Below are example soil tests for saline, sodic, saline-sodic and a no salt issue field to give you an idea of what you are looking for.

The photos below are of saline and sodic fields in North Dakota. Can you tell the difference between the saline and sodic sites?

Soil Test Examples Provided by

Saline Soil	Sodic Soil

Saline-Sodic Soil	No Salt Issue
Managing a saline-sodic soil is a balancing act. Start by managing the salinity by managing the water table. If you are able to lower the salinity level (less than 3 mmho/cm) then consider management options for sodic soils. If applying any kind of  soil amendments – keep an eye on your soluble salt levels over time.	If the soil test is low in both soluble salts and %Na, the field is not suffering from a salt issue. *Keep in mind* If you are composite soil sampling salt problems will likely not be detected, and the field will look “normal”. ALWAYS sample a an area of poor productivity and a good area, for comparison, to determaine if salts are the problem.