Bracken
The bracken on the Heath is confined to a well defined zone with a
boundary of gorse on one side and the narrow stream on the other. It seems
unlikely that either of these boundaries would act as an effective barrier to the
spread of bracken but the fact remains that the heather, grassland and
woodland are almost devoid of bracken. In my professional capacity as warden
of Danbury Common I am familiar with the advance of bracken in all three of
these habitats in recent years and would like to know what factors are inhibiting
it on Tiptree Heath. Well established dense heather must be difficult even for
bracken to colonise, but open grassland and secondary woodland would seem to
present few problems.
A large mixed colony of heath spotted orchid and common spotted orchid
(Dactylorhiza fuchsii (Druce) Sod) plus probable hybrids exists in the bracken.
The unfurling fronds certainly protect the orchids from picking, but it also
seems likely that the dank micro-climate beneath the bracken produces mildew
on the orchid seed heads and inhibits germination as well.
Large clumps of creeping willow (Salix repens Linn.) grow near the orchids
together with several unidentified sallow hybrids. Devilsbit scabious (Succisa
pratensis Moench) changing forget-me-not (Myosotis discolor Pers.) and many
fine tussocks of purple moor grass (Molinia caerulea (L.) Moench) also grow in
the bracken.
Woodland
Woodland is a recent arrival on the Heath and generally consists of large
numbers of just two or three species with an almost total absence of woodland
shrub and herb species. The most common tree species are pedunculate oak
(Quercus robur Linn.) plus various oak hybrids; silver birch (Betula pendula
Roth) downy birch (Betula pubescens Ehrh.) goat willow (Salix caprea Linn.)
plus various sallow hybrids; and aspen (Populus tremula Linn.).
The tree and shrub species list becomes more respectable when we turn our
attention to the ancient ditch-and-bank boundaries of the Heath. Several of
these we now realise are relic woodland hedges, dating from a period when
woodland adjoined at least two sides of the Heath. Although no map examined
so far confirms the theory, the following true-woodland species recorded in one
short hedge seems to support it:
Wild Service (Sorbus torminalis (L) Crantz)
Small-leaved Lime (Tilia cordata Mill)
Hazel (Coryllus avellana Linn.)
Hornbeam (Carpinus betulus Linn.)
The woodland ground layer has not survived in the present-day hedge.
Nearby on the boundary is a stretch of hawthorn hedge (Crataegus monogyna
Jacq.) which also contains woodland hawthorn (C. laevigata (L.) Poir.). Once
again, no woodland ground layer survives in the hedge, but a few feet into the
Heath can be found two or three clumps of primrose (Primula vulgaris Huds.)
14