Pulsatilla vulgaris (L.) Mill. - Plantlife

Historically Pulsatilla has been recorded sporadically along 7 km of an Anglo-Saxon chalk ditch
and bank between Burwell and where the Cambridge-Newmarket railway crosses the dyke to
the SE. The majority of plants are confined to the SW-facing banks particularly where the
grassland has been kept open by rabbits, infrequent mowing or burning. A few plants also
occur on the top of the dyke, where grass growth is reduced by trampling, and on the
adjacent Newmarket Heath which is cut fortnightly, although no plants have been recorded
from the heath since 1984. The dyke itself was not grazed for many decades leading to the
development of a thick sward of Bromopsis erectus. Accidental burning of one section in the
1970s led to a dramatic increase in flowering numbers although numbers subsequently
declined to pre-1970 levels. Since then localised mowing has led to localised increases on
some sections (e.g. adjacent to Newmarket Heath) and in 2003 the introduction of wintersheep
grazing (and stock-fencing) led to increased flowering on the southern section. In the
same year four plants appeared (with Himantoglossum hircinum) on the steep SE-facing bank
of the A14 c. 300m to the N of the nearest plants on the Dyke itself (TL603632; Leslie, 2004).
These presumably established from seed dispersed to the site on mowing machinery.
Fleam Dyke (SSSI)†
In the 1960s a small population was recorded on an ungrazed SW-facing bank of a mediaeval
chalk ditch and bank immediately to the NW of a small tumulus. It was last seen in April 1973
when the plants were dug-up by the farmer in order to reduce the number of botanists visiting
the site (Marren, 1999).
Hildersham Furze Hills (SSSI)†
A small population formerly grew (with Dianthus deltoides) on the spine of the easterly (Sand)
hill on a sandy soil (pH 5.2) derived from glacial sands and gravels (Wells & Barling, 1971).
During the 1950s there were never more than 3-4 clumps with 20-30 flowers (Trist, 1988).
Annual rabbit damage was intense, especially during droughts, although this declined
following the advent of myxomatosis in 1954. Three plants survived on the spine of the hill
into the mid-1980s despite the spread of rank grasses and blackthorn scrub (Trist, 1988). By
1990 only one, non-flowering plant remained and it has not been recorded since despite
improvements in the condition of the grassland and the removal of scrub (Compton, 2010
onwards).
BEDFORDSHIRE (v.c.30)
Barton Hills (NNR)
Several large sub-populations occur towards the S end of this reserve in exceptionally rich
chalk downland turf on steep, predominantly S- to SW-facing slopes and spurs where soils are
very shallow and competition from coarse grasses is restricted (Wells, 1968; Welsh, 1983). A
few plants also occur on ancient field systems at the N end of the reserve where grazing is
more variable. Historically the site was heavily grazed by sheep but management was
neglected from 1934 to 1954 resulting in the development of a dense sward of Bromopsis
erectus (Wells, 1968). This was burnt-off in 1954 and sheep grazing re-introduced for nine
months of the year (2-3 ac -1 ), although rabbit grazing declined dramatically due to
myxomatosis. Since the mid-1980s the site has been grazed by rabbits all year (although
populations have increased in recent years) and sheep (0.4 ha -1 ) from May to December
(inclusive) although this has been relaxed in recent years due to a rise in the rabbit population
(Bailey, 1996). This has resulted in an increase in the flowering population to over 5,000
crowns although flowering is suppressed in some years by heavy grazing (G. Bellamy, pers.
comm.). The Barton population of Pulsatilla is well known and attracts many visitors during
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