Moisture regimes in Soil Taxonomy are based on the amount of time the soil (within the moisture
control section) is moist, dry, or has ""aquic conditions"" in ""normal years"". The moisture pattern is
commonly estimated from climatic data, however factors such as run off, run on, aspect and a water
table also must be considered when making estimates. In some places we (the soil survey staff) appear
to have over used climatic data. It seem reasonable that some soils, in oxyaquic and aquic subgroups,
in an area with a regional xeric regime would have a udic regime. If you are using soil series I would
discourage the use of a series that is from a udic climate. The moisture pattern of the near surface
layers, salt concentrations, and/or water table may be useful in defining the series.
