THE BIRD-COMMUNITY STRUCTURE OF EPPING FOREST
SINCE 1800
by PAUL A. MOXEY
Epping Forest Conservation Centre, High Beach, Loughton, Essex.
INTRODUCTION
The modern Epping Forest comprises some 2,430 hectares of woodland
and grass, together with small relict patches of heathland and water areas; it
extends in the form of a crescent from Wanstead Flats, at its southern end, to a
little beyond Epping in the north, a distance of approximately 19 km.
The geological structure is but one of several factors determining the
ecological character of the Forest. Broadly speaking, it falls into three divisions.
In the south, around Wanstead, the flat terraces of the Thames gravels
dominate the physical landscape; in the central area, through Woodford and
Buckhurst Hill, isolated patches of glacial gravel lie on the predominant
London Clay; in the northern section, from High Beach to Epping, a long ridge
of Pebble Gravel and Bagshot Beds overlies the Claygate Beds, with the London
Clay exposed on the lower slopes. In this northern section the pattern is com-
plicated by deposits of Chalky Boulder Clay and de-calcified glacial till.
It has been estimated (Qvist, 1958) that approximately two thirds of the
Forest area is wooded, the major tree species being beech {Fagus sylvatica),
common oak (Quercus robur), hornbeam (Carpinus betulus) and silver birch
(Betula pendula). Whilst the pattern of vegetation has to a large extent been
modified by a long history of management, the present distribution of the major
tree associations to some extent reflects the underlying geology. Beech tends to
be dominant on the sands and gravels, with silver birch as a coloniser of acid
grassland, heath, or where a gap occurs in the beech canopy. In the area north-
wards from High Beach, a comparison of the present situation with that shown
on the first edition of the six-inch Ordnance Survey maps (published c. 1870)
reveals that many areas of former grass and heath are now under birch. Horn-
beam, associated with oak, is more characteristic of the intermediate, loamy
Claygate Beds, but there is evidence that, in the past hundred years it has
tended to be out-topped and killed by beech (Baker, Moxey and Oxford, 1978).
On the heavier clay soils oak dominates, often with a dense understorey of holly
(Ilex aquifolium) but the wetter grasslands of the clay areas are being invaded
by common hawthorn (Crataegus monogyna) and blackthorn (Prunus spinosa).
The wooded areas have many of the plant species considered indicative of
ancient woodland (Peterken, 1974), including wild service (Sorbus torminalis).
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