thyme-leaved sandwort (Arenaria leptoclados (Rchb.) Guss.) exist in arid,
sandy soil where patches of bare ground among short turf allow them to spread.
Fern species have been recorded in the grassland and woodland areas.
Broad-leaved buckler fern (Dryopteris dilatata (Hoffm.) A. Gray), narrow-
leaved buckler fern (D. carthusiana (Vill.) H.P. Fuchs) and male fern (D. filix-
mas (L.) Schott) all grow in the deep shade of a large sallow thicket.
A species absent from the lists that we would like to confirm as surviving is
allseed (Radiola linoides Roth) which until recently was thought to be extinct in
Essex. It was refound in sandy ruts on Tiptree Heath in 1966 and again in the
same spot in 1970. The plant is easily overlooked, as it is often less than five cms
in height. Gibson found the species in six sites including Tiptree Heath, since
when it has declined to the point where it is now a national rarity.
Invertebrates
This is the least studied group on the Heath. This is unfortunate because
the invertebrate fauna is closely allied to the flora and geological strata so the
importance of the flora may well reflect a correspondingly important in-
vertebrate population. Attempting to stave off the threat of a football pitch on
the Heath, the late Mr F. Buck attracted publicity in his efforts to confirm the
presence of Epsinus maculipes. This small spider was recorded on the Heath in
the 1930's and is not known anywhere else in the British Isles. He also found the
rare beetle Chrysolina sanguinolenta Linn. on toadflax (Linaria vulgaris Mill.).
Burying beetles and dung beetles are found where rabbits congregate.
Necrophorus humator Goeze and N. investigator Linn. are commonly found
with carcases, and tunnels of the minotaur (Typhaeus typhoeus Linn.) are
noticeable on bare ground. Several of the spectacular spotted longhorn
(Strangalia maculata Pod.) were found on Hypericum spp. during the
coleoptera survey organised by Mr G. Ackers in 1977.
A total of 52 species were recorded during the survey, bringing the total to
79 beetle species. Missing from the list however was the small 5mm leaf beetle
species Lochmaea suturalis Thomson, known as the heather beetle. This insect
is specific to heather, its food plant for both larval and adult stages, and is
usually found in upland moorland areas where square miles of heather flourish.
Assisted by favourable conditions for two or three consecutive years, oc-
casionally its numbers build up to plague proportions and large areas of heather
are destroyed, with economic repercussions to the commercial grouse and honey
industries. Damage to the plant occurs through leaf grazing and stripping of the
bark, allowing water loss resulting in rapid browning and the probable killing of
the plant.
In August 1978 two acres of ling were seen to be dull and lacking in flower
buds, in contrast to neighbouring stands of bell heather and cross-leaved heath.
One week later a distinct brown tinge was noted in affected areas, and at this
stage coleoptera larvae were collected and despatched by the Colchester Natural
History Museum to the Entomological Department of the British Museum. An
infestation by Lochmaea suturalis was rapidly confirmed, which, thankfully,
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