They might show up as slightly acidic or slightly alkaline because of this. The pH scale measures how strongly acidic or alkaline a solution is using a set of values from pH 0 to pH 14.

The pH scale goes from 0 to 14 with pH 7 as the neutral ... that are held in the organic matter. Soils tend to become acidic as a result of: (1) rainwater leaching away basic ions (calcium, magnesium, ...