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Benfleet-Hadleigh Downs in the early 1950s as one of the best flower-rich grassland sites in
southern England. A sad reflection on the impotence of conservation organisations to appreciate the
loss, let alone do something about it. Each year the areas of open grassland get smaller, and the
Tordylium patches are now confined to old fire sites completely surrounded by scrub.
Two small patches persisted near the north-west corner of the downs at Benfleet, from at least the
1970s, with another detached colony some 300m to the east. The two small patches occurred on
opposite sides of the main track at the top of the Downs. One of them, still just survives, with a
dozen or so plants appearing each year, sandwiched between the track and scrub, the other colony,
with only 3 plants in 1993, had disappeared by 1995, outcompeted by rank grass. The detached
colony, however, occurs on the slopes of a small incline that forms a grassy clearing, where it grows
with abundant Petroselinum segetum and Lathyrus hirsutus. A chance fire at the site in 1991,
however, seems to have turned around the population, as several thousand Tordylium plants
germinated in the ash, and gave rise to a dense 2x2m patch in 1993, that had expanded to a triangular
area of some 10 x 10 x 10m by 1995. The site is now declining, as rank grasses move in to compete
with the Tordylium, but the production of tens of thousands of seeds in 1995. was taken advantage of
by the author, to experiment with seeding new sites. Numerous suitable thermophilic spots along the
scrub margin were tried, but the only one that gave any success was on another steep slope that had
recently been burnt, very close to the original two small patches, by the track leading down to the
station. Here the fire site had been colonised by Alexanders, which by August 1995 had died back,
and a considerable quantity of freshly gathered Tordylium seed was shallow-buried in the dry sterile
ashes. By the summer of the following year at least 1,000 plants had germinated, and by the summer
of 1999, seed from the colony had been rain washed down the slope, and across the track, giving rise
to additional colonies spread out in a fan downslope. This is now the most successful patch and
points the way forward for ensuring that we can keep healthy colonies going on the Downs. The
successful formula seems to involve: a) use of fresh seed; it loses its viability within a few weeks of
storage, b) seeding the sterile soil of a recent fire site in a thermophilic spot, ideally on a well drained
slope, c) actually burying the seed slightly; all sites where it was simply scattered on the surface
failed to develop seedlings. Now that dense scrub or rank grass has encroached all its former open
sites on the Downs, it is only likely to survive in any quantity, if at all, if patches are deliberately
fired to create a seed bed for it, and seed is artificially introduced to these new sites.
It has long been suspected that Tordylium probably occurs at a number of sites along the north bank
of the Thames that have yet to be discovered. In about 1974, Mervyn Southam discovered a patch on
a verge well north of Tilbury, and in June 1999, a new colony was found on either side of a track in a
Suntrap hollow at Broom Hill, Tilbury on an EFC meeting. At the latter site, several hundred plants
occurred on waste ground in front of a hedge on one side of the track, and about 20 occurred on the
banked margin of an arable field on the other side. This find suggests that the seed may well be
moved considerable distances on the muddy wheels of vehicles. Alternatively there may some
animal or bird which is capable of aiding dispersal. How do large Umbellifers disperse their seed?
Does the strong smell of pigs given off by withering Hogweed umbels attract w ild pigs so that they
root around and carry the seed on their hairy backs or on their feet? - or can the seed pass
successfully through the gut of some animals or birds? Tordylium seed is markedly flattened, thus
aiding short range dispersal by w ind. and is covered by short stiff hairs which might allow it to be
dispersed on the fur of small mammals. According to Roger Payne (personal communication) some
small mammals hoard Umbellifer seed. A typical Mediterranean plant of waste and cultivated
ground, it is not at all well adapted to our climate. Despite its confinement to thermophilic spots it is
capable of surviving quite heavy frosts in the vegetative state, and given a warm sunny spring
produces flowers as early as April/May (in my garden) which can be hit by a late frost. Though ripe
seed is not normally dispersed until August/September, in some years it ripens and begins to drop in
July. It is avidly grazed by rabbits which it may avoid to some extent by growing in dense clusters,
Essex Naturalist (New Series) 16 (1999)