seems confined just to the ling species. It is likely that the affected plants will
die, and also likely that natural checks will bring the heather beetle population
back into balance. The weather in late July and early August was not favourable
to larval development, and in addition it is known that severe infestations are
frequently heavily parasitized by certain flies.
The Heath supports an impressive moth population. The Colchester
Natural History Society surveyed the moths on the wing in June 1976, July 1977
and August 1978, using a mercury-vapour lamp sited in the Heather area. 120
' macro' species have been recorded to date. Heather-associated species include
the true lovers knot (Lychophotia varia Linn.) and the scarce and local
narrow-winged pug (Eupithecia nanata Hubn). Willow and sallow
support populations of pale prominent (Pterostoma palpina Clerck.), swallow
prominent (Pheosia tremula Clerck.), poplar hawk (Laothoe populi Linn.) and
puss moth (Cerura vinula Linn.). Other uncommon or spectacular species
include maple prominent (Lophopteryx cucullina Schiff.), scarce footman
(Eilema complana Linn.), emperor moth (Saturnia pavonia Linn.), privet hawk
(Sphinx ligustri Linn.) and the green form of the barred red (Ellopia fasciaria
Linn.)
At only 18 species the butterfly population is probably under-recorded.
There is a noticeable predominance of the grass-associated Satyridae species
such as the small heath (Coenonympha pamphilus Linn.), meadow brown
(Maniola jurtina Linn.) and gatekeeper (M. tithonus Linn.). As expected there
is a corresponding dearth of Vanessid and Pieridae species due to the com-
parative scarcity of their respective food plants of stinging nettle (Urtica dioica
Linn.) and cruciferous species. Alder buckthorn (Frangula alnus Mill.) grows
on the Heath in small quantity and larvae of the brimstone (Gonepteryx rhamni
Linn.) were found on it in 1977. The small copper (Lycaena phlaeas Linn.) is the
commonest Lycaenidae species, probably because of the extreme abundance of
sheeps sorrel (Rumex acetosella Linn.). The holly blue (Celastrina argiolus
Linn.) was recorded in 1977. Surprisingly it seems that the Heath lacks the
green hairstreak (Callophrys rubi Linn.) in spite of the abundance of gorse,
although the almost total absence of broom (Sarothamnus scoparius (L.)
Wimmer ex Koch) may be the critical factor.
BIBLIOGRAPHY
GIBSON, G. S. (1862). The flora of Essex. London.
GIMINGHAM, C. H. (1974). An Introduction to Heathland Ecology. Oliver & Boyd, Edinburgh.
JERMYN, S. T. (1974). Flora of Essex. Essex Naturalists' Trust Ltd, Colchester.
MORANT, P. (1760-68). History and Antiquities of the County of Essex.
POLLARD, E., HOOPER, M. D. & MOORE, N. W. (1974) Hedges Collins, London.
RACKHAM, O. (1976). Trees and Woodland in the British Landscape. Dent, London.
19