added Walden Forest, the name given by the Forestry Commission to the
woods surrounding Saffron Walden. With the exception of Epping and Wintry,
the ancient forests survive only in fragmented form. The principal tree up to
Anglo-Saxon times was the small-leaved lime. This was later replaced by
hornbeam and beech; oak was always present, together with holly, hawthorn,
blackthorn, crab-apple and service (Rackham, 1978:49). Lime survives in
parts of north Essex and at least three associated microlepidoptera occur with
it. Hornbeam and beech are still dominant in southern Essex. Though these
trees have characteristic insects, they are few in number. The ground flora
under them is sparse, so one must look in these woods for species which feed on
leaf-litter rather than herbaceous plants. Nevertheless, even in the south there
is sufficient mixed woodland to support virtually all the microlepidoptera
characteristic of this habitat.
Now that forests are no longer maintained for deer-hunting and ship-
timber, the commercial interests which control their composition are causing
conifers to replace hardwoods. Many, but not all, of the microlepidoptera
dependent on conifers have come with the trees; some, however, require
mature, well-spaced pines which are almost absent from Essex. A lot of
nonsense is repeated about the evil effects of coniferisation; Walden Forest,
which is coniferised, has a richer insect fauna than Epping Forest, which is not.
The policy of the Forestry Commission is to plant an 'amenity belt' of
deciduous trees along the borders of their plantations, sometimes introducing a
greater variety than would otherwise be found. The majority of insects
frequent the margins of woods and these belts provide them with the habitat
they require. Moreover the Commission maintains broad, grassy rides which
support a wide range of herbaceous plants, again good for Lepidoptera. The
relatively frequent felling of the timber crop and the subsequent reafforest-
ation is not dissimilar to the now seldom practised regime of coppicing which
was so advantageous to the forest-floor species. During the late 1960s the
Forestry Commission decided to do away with the deciduous tree element and
sprayed Walden Forest from the air with a defoliant. Luckily this iniquitous
policy was reversed before the second year of the spraying programme and
most of the trees recovered. As long as the amenity belts are maintained, the
entomologist need not be too worried about the plantation of conifers.
(2) Heathland. We are badly off for heather heathland in Essex. The largest
area is Tiptree Heath and that is now "a mere fragment of the huge area which
once embraced 16 parishes" (Forsyth, 1978:4). Birch scrub has swamped most
of the heather-clad ground in Epping Forest and only small patches of heather
survive in central Essex. All but three or four of the ericetal species of
microlepidoptera appear to be extinct in the county.
(3) Downland. Although surface chalk is found in north-west Essex and around
Grays and Purfleet in the south, we have no true downland. The north-west is
under intensive agriculture and most of the chalk has been quarried away in the
south. Species that require downland to range over like Ancylis comptana are
absent, but others which can subsist on a small patch of foodplant survive
precariously on roadside verges. Grays Chalk Pit, now under threat of building
11