GRAYS CHALK QUARRY
by D. J. L. Agassiz
This nature reserve is one of the richest places in the county for variety of Lepidoptera, which is
surprising for an artificial habitat
The Grays-Purfleet ridge of chalk has two chief advantages: first it comprises a large area of
derelict land much of which is bare chalk and has not been touched for decades; secondly it is only a
short distance (as the moth flies) from the North Downs of Kent
Grays Chalk Quarry, where quarrying ceased before 1930, covers an area of some 37 acres. Much
of it is quarry floor, covered with dense scrub - birch, hawthorn and dogwood with stands of sallow,
oak, aspen and the occasional wayfaring tree or spindle. Clematis abounds and in the denser parts
there is a thick undercover of ivy. In the more open areas there is a rich ground flora of chalk plants;
this is especially so round the edge of the quarry where the tertiary sand was scraped off leaving bare
chalk which in many places was never quarried out In these parts the reserve resembles chalk
downland.
The butterfly fauna is not remarkable. The chalk downland form of the silver-studded blue
(Plebejus argus) once occurred here, but that has long since gone (Guide, p.36). Speckled woods
(Pararge aegeria) are increasing in the more wooded areas, the green hairstreak (Callophrys rubi) is
firmly established and holly blues (Celastrina argiolus) abound over the ubiquitous ivy. Of the day-
flying moths, the burnet companion (Euclidia glyphica) is common and the narrow-bordered five-
spot burnet (Zygaena lonicerae) occurs in small numbers. Evidence of clearwings can often be seen:
the lunar hornet moth (Sesia bembeciformis) in the sallows and the orange-tailed clearwing
(Synanthedon andrenaeformis) in the wayfaring trees.
Among nocturnal moths the chalk carpet (Scotopteryx bipunctaria) is resident and well
established. The maple prominent (Ptilodontella cucullina) and maple pug (Eupithecia inturbata)
are often found, although most maple grows in surrounding hedgerows rather than in the reserve itself.
Several species of microlepidoptera are resident here which can be found nowhere else in Essex.
Much of the value of the quarry lies in the vast area of other quarries nearby, so that attempts at
dispersal by the insects do not inevitably result in suicide. The nearness of salt-marsh and freshwater-
marsh means that on a good night a very large number of species can be seen; for example, on 27th
July 1984 no less than 235 different kinds were recorded, 104 of them macrolepidoptera.
It is confidently hoped that a secure lease of the quarry will shortly be granted to the Essex
Naturalists' Trust by Blue Circle Industries, which will enable the reserve to be managed so that the
habitats needed by lepidoptera can be maintained; but impending development of surrounding land
may diminish the ecological richness of the area in years to come.
STOUR AND COPPERAS WOODS
by M. E. Anthoney
Situated in the north-east of the county three miles from Harwich, Stour Wood (134 acres) and the
neighbouring Copperas Wood (34 acres) together constitute one of the most entomologically
important sites in Essex. Adjacent to the southern bank of the River Stour, they form part of a large
and varied conservation area; both woods are SSSIs, as are the salt-marshes, reed-beds and mud-flats
(600 acres) of the Stour estuary. In addition, half a mile of rough scrubland (11 acres) connects the
two woods.
Both woods comprise 90% sweet chestnut and some 30 other species of tree occur, Oak and birch
are present in numbers, with more unusual species such as wild service, spindle and small-leaved lime
also represented and indicative of ancient woodland. Records suggest that coppicing has been carried
out for at least 300 years. Active management has decreased in the past 50 years to the point where
most of the coppice areas have become neglected and the resulting thick canopy has severely limited
the range of ground plants, but past coppicing practice ensures that in the remaining open areas nectar-
rich flowers such as bugle and yellow archangel still thrive.
23