Changes

Evaluating the soils can also give clues as to the depth of groundwater. The primary clue is the presence of mottles, or areas of soils discoloration, as shown in the image to the right. This condition is primarily caused by the deposits of metal ions left on the soil while in saturated conditions. Technically, these mottles are known as redoximorphic (redox) features—features caused by the reduction and oxidation of chemical compounds while saturated. While the chemistry may be complex, the signs are easy to see. Look for the highest elevation of redox features in the soil profile to determine the limit of seasonally high groundwater.

''[[Practitioner's Tool / Slope and Topography|Proceed to Step 5: Slope and Topography]]''