Soils with Plinthite - Soil Geography of the USA: A Diagnostic-Horizon Approach - page 294

Fig. 25.1 Plinthite in the
Dothan series (near blade of
shovel; photo compliments
of Dr. Joey Shaw)
Soils with plinthite commonly have a thermic soil-temperature regime (82 %), a
udic soil-moisture regime (91 %), a siliceous (78 %) or kaolinitic (20 %) mineral
class, and a loamy (89 %) particle-size class (includes coarse-loamy, fine-loamy,
and loamy) (Fig. 25.2 ).
25.4 Distribution of Soils with Plinthite
Soils with plinthite occur in two general locations in the USA: the Ultisol region of
the southeastern coastal plain (AL, GA, MS, FL, SC) and in the Alfisol region of
eastern TX. The total area of soils containing taxonomic plinthite is 48,746 km 2
(Fig. 25.3 ). Three soils, the Tifton, Dothan, and Fuquay series, comprise 48 % of the
plinthitic soils in the USA.