CONSERVATION
&
MANAGEMENT
Resurvey of the Corticolous Lichen flora of Epping Forest
R.W. JAMES ' & L. DAVIES 2
1 Dept, of Botany, Natural History Museum, London SW7 5BD
2 Imperial College. London, SW7 2AZ
Abstract
Epping Forest, located partly in London, is an ancient, designated site of European importance with
a long established continuity of woodland including Oak, Hornbeam and Beech, interspersed with
heathland areas. Its corticolous lichen flora has been documented since the 18th Century peaking in
diversity in the late 1800s and with lowest number of species recorded in the 1970s. Signs of
recovery in the lichen flora were first noted in 1989-91 and the present survey records highest
diversity for over a century. The emerging flora is typical of a now wide-ranging pioneering community
signifying initial recovery from the effects of acid rain and sulphur dioxide. However, the more
common species are those associated with urban, roadside and agricultural locations, suggesting
that the present flora is responding to more widespread conditions of eutrophication, the exception
being in the central, more dense, sheltered areas of the Forest where only a few exclusively woodland
species, such as Opegrapha ochrocheila, are colonising.
Introduction
Recent surveys in London (James et al. 2002, Davies et al. 2002) indicate the extent of the recent
recovery in corticolous lichens in London in the last decade. The return of species not seen for a
century and a significant number never before recorded in the Capital have stimulated further
investigations at sites where the impact of sulphur dioxide pollution and associated acid rain almost
totally destroyed a once diverse and interesting flora. This paper records the results from a recent
preliminary survey in Epping Forest.
Epping is an ancient woodland site situated partly in the London borough of Waltham Forest (20%)
extending into the more rural area of Epping Forest District Council (80%) in the county of Essex.
The site, awarded candidate Special Arca of Conservation Status (cSAC) under the European Habitats
Directive (92/43/EEC) for its ancient Beech and heathland areas, extends over 1600 hectares
(513839N, 000121 E) and comprises 70% deciduous woodland (Beech, Oak, Hornbeam), with
marsh, fen, scrub, heathland, lakes and ponds. It was selected to represent Atlantic acidophilus
Beech forests in the south-eastern part of the UK. The epiphytes at this site have declined, largely
as a result of air pollution, but it remains of outstanding national importance for its flora and fauna,
Essex Naturalist (New Series) 20 (2003)
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