SOILS
Soil classification
Table 1 indicates the main soil groups associated with the geological
deposits. The soil group names are from the classification of soils used by the
Soil Survey of England and Wales (Avery 1973) which is a national framework
within which to introduce the soils of the Forest. The things classified are soil
profiles, limited to a volume (about 1 m3) that can in practice be adequately
described and sampled as a single entity. A soil profile thus consists of suc-
cessive horizons, commonly aligned roughly parallel with the ground surface,
within the biologically active upper metre of the Earth's mantle. Profile classes
are defined at four levels, namely major group, group, subgroup and series, by
progressive division. The extended legend to the Soil Map of England and
Wales published at a scale of 1 to 1 million (Avery et al. 1974) summarises the
classification, but since the terminology is likely to be unfamiliar to most non-
specialist readers, a brief outline of what one needs to know is given below.
The factors which influence the development and distribution of different
soil profiles in specific localities include permeability and water regime, nutrient
status, lithology, and man, directly and indirectly through vegetation. The
water regime imparts characteristic properties to the profile. In well drained
and moderately well drained soils the subsoils are well aerated showing chiefly
Table 1. Classification of the principal soils of Epping Forest.
Major Soil Group Soil Group
Brown soils Argillic brown
earths
Podzolic soils Gley-Podzols
Ground-water gley soils Alluvial gley soils
Argillic gley soils
Humic gley soils
Surface-water gley soils Stagnogley soils
Lithology and Geology
Loamy; Bagshot and Claygate Beds
Loamy over gravelly: Glacial and
River terrace Gravels
Stony loamy over clayey; Pebble Gravel
Loamy and clayey; river alluvium
Loamy; Bagshot and Claygate Beds
Loamy and sandy; Bagshot and
Claygate Beds
Loamy over clayey; drift over
London (or Claygate Beds) Clay
Clayey; London (or Claygates Beds)
Clay
Clayey; Boulder Clay
Stony loamy over clayey; Pebble Gravel
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