The Electrical Conductivity of a saturated soil Extract (ECe) is the most useful and reliable measure of salinity for comparing between soil types, as it accounts for soil texture. For example, a light sandy soil will hold much less water than a clay when both are saturated. However, if both have the same amount of salt, the dissolved concentration will vary between the two soils types and therefore impact on crop or pasture production differently.
The standard EC1:5 reading in water can be used to estimate ECe using conversion factors, as the correct method of ECe measurement is expensive and must be carried out in a laboratory. These conversion factors are guides only and the actual conversion may vary significantly.