When young in September it makes a linear mine before cutting out its first small case. C.
limosipennella (Dup.) makes a longer final case (9-11.5 mm.) from a leaf margin in the spring,
and in which it spends its second winter, fixed at an angle on twigs, before pupation and
emergence. When young in September it makes a small but clear narrow mine and then cuts
its first case, overwintering the first time when it has cut the second.
Teleiodes fugitivella (Zeller) is a common and widespread species often taken in light traps
in June and July. Its larva feeds in May in a folded or spun leaf of elm from which it readily
descends on a silken thread when it is disturbed.
Acleris boscana (Fabr.) is also common and widespread, Essex being one of the better
counties for it. The larva feeds in a spinning between two leaves spun one on top of another,
although when small it turns over the edge of a leaf in which it feeds. There are two generations,
larvae in May and June giving the brightly-marked moths of the summer generation, and those
in August and September producing the more numerous, but greyer moths which overwinter as
adults.
Epinotia abbreviana (Fabr.) is widespread and abundant. Sometimes the adults will fly in
a swarm from an elm hedge where they are on the wing from June to August. The young larva
feeds at first in an unopened leaf-bud causing an arc of holes to appear near the base of a leaf
in due course. It then spins the leaves one above another in May and early June. Although
primarily on elm it sometimes feeds on Maple.
Finally the Pyralid moth Pempelia formosa (Haw.), a species whose larva prefers bushes to
trees. The larva feeds openly by day in a slight spinning along the midrib of the upperside of a
leaf. It is found in May giving moths in June and July.
References
Emmet, A. M. (1981) The Smaller Moths of Essex. Essex Naturalist 6 (New Series). Essex Field Club.
Emmet, A. M. and Pyman, G. A. (1985) The Larger Moths and Butterflies of Essex. Essex Naturalist 8
(New Series). Essex Field Club.
4) Diptera. Mr. D. A. Smith
Very little has been published specifically about Diptera (two-winged flies) and their association
with Elms in Essex and as will be seen from the references cited, this chapter has drawn heavily
on information gathered elsewhere in Britain.
The association of flies with elm falls into two categories;
a) Flies, the larvae of which live actually on or within the matter of the tree itself (i.e. in the
leaves or in decaying wood.
b) Flies with larvae that feed in fungi on elm trees. In addition there are many flies that have a
very loose association with elm. The larvae of some species will predate other larvae that live
under the bark, but will quite happily live on another suitable tree species. Many species of
adult fly will use elm foliage or the trunk of the tree as a hunting ground or simply as shelter.
The flies of some 20 families of British Diptera (of 87 families known from Britain) have
been found in dead or decaying elm wood, but are not confined to elm. An example of this is
to be found in the genus Systenus (Dolichopodidae). The five British species are all associated
with exudations or rot-holes in decaying trees, often in ancient woodland. All five are typically
recorded from elm, but have also been found on other trees. Three species of this genus have
been found in Essex (Systenus leucurus, S. pallipes and S. scholtzii) but none specifically from
elm.
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