Elm in the Pollen Record
Palynological studies in East Anglia (Birks, 1976) have shown elm (species unknown), to have
been a regular feature, at least of the later interglacial periods, of the Pleistocene, including a
record from the Hoxnian interglacial from a sample gathered from Mark's Tey in Essex. In
most of the pollen diagrams, following a period of climatic warming after the previous
glaciation, Birch and Pine appear, followed, as the climate further warmed, by species such as
Elm, Oak and Alder. Typically grasses and herbaceous plants also begin to become more
frequently represented in the pollen diagram as presumably the large herbivorous members of
the vertebrate fauna of those times maintained open grassland to the detriment of the expansion
of woodland. Elm begins to decline and to a lesser extent Oak, presumably due to a combination
of browsing pressure and a cooling climate, leading up to the next glaciation. It is certain that
the elms present at these times were wiped out by each succeeding glaciation.
During the present interglacial period, a significant and universal feature of pollen diagrams
in N. W. Europe has been the 'Elm Decline'. A marked decrease in the levels of elm pollen is
reported, somehow associated with the rise of Neolithic agriculture (Rackham, 1980). It is
conjectured (Lamb, 1979 and Rackham, 1980) that Elm Disease is implicated in the 'Elm
Decline', it being the only possible cause of such widespread synchroneity in this event.
A recent analysis of the pollen record from the Mar Dyke in south Essex (Wilkinson, 1988)
shows an elm decline associated with a rise in cerealia pollen (also Ribwort-Plaintain) radio-
carbon dated to 4650 ± 90 bp; a rather late date for the 'Elm Decline' compared with other sites
but as the author states, it is 'strongly associated with anthropogenic activity'. Elm later
experiences a period of apparent increase, interpreted in conjunction with other tree pollens, as
increased forest cover in the late Neolithic and continuing to the early Bronze Age. The Mar
Dyke pollen diagram shows what is interpreted as secondary elm decline as a result of further
and continued anthropogenic impact on the environment from the early Bronze Age (1630 be)
onwards.
A pollen diagram from a sample collected from the Lodge Road Bog, Epping Forest (Baker,
Moxey and Oxford, 1978) indicates that elm has been present in the Epping Forest area since
at least 4290 ± 100 bp (late Neolithic to Early Bronze Age onwards). An increase in elm pollen
is shown on the diagram, occurring during the late Saxon period following a decrease in
levels of lime (Tilia cordata) pollen. Interestingly a sample of the contemporary pollen rain was
collected from a moss 'cushion' located near the Lodge Road Bog for comparative purposes.
No elm pollen was recorded, despite elm being present in the local area, although not in the
immediate vicinity of the sample.