A numerical index of soil development, the POD Index, was developed and applied to 723 pedons of United States soils that either exhibit or are developing, podzol (spodosol) morphology. The index is determined solely from morphologic (field
) criteria, and provides the first soil development index for podzol and podzol-like soils that does not use chemical data. A comparison of POD Indices for spodosols of differing drainage revealed that maximum development occurred in wet soils. Additionally