Table 2. Analytical data for selected horizons of representative Forest soils.
Soil subgroup Depth Nature of Clay Organic pH
and series (cm) horizon % Carbon % (water)
* From woodland sites on Sheet TQ 59, Harold Hill (Sturdy, 1971)
brownish, yellowish or reddish colours. These, and to some degree other soils
too, lose bases from upper horizons through rainfall translocating dissolved
nutrients into the subsoil or laterally above impermeable horizons out of the
profile. Thus, soils tend to be more acid in upper horizons; the process is
described as leaching. In soils with impeded drainage or a high water table,
compounds of iron and manganese are subject to reduction, mobilisation and
redeposition giving the subsoil a mottled appearance in grey, yellow and rusty
colours. This process is called gleying, and soils with such characteristics well
developed are termed gley soils. They are subdivided into ground-water gley
soils with a relatively permeable subsoil affected by free ground water, and into
surface-water gley (stagnogley) soils which have a subsurface layer sufficiently
impermeable to seasonally hold up water. Gley soils may also show evidence of
removal of clay by percolating rainwater from surface horizons and redeposition
in lower argillic horizons. Paleoargillic horizons are a special case and
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