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STATUS, DISTRIBUTION
and IDENTIFICATION
Notes on Essex Specialities. 3: Annual Sea-purslane Atriplex pedunculata L.
CHRIS GIBSON
English Nature, Harbour House, Hythe Quay, Colchester COl 8JF
Introduction
Annual Sea-purslane Atriplex pedunculata (formerly Halimione pedunculata) (Chenopodiaceae) is
a rare annual plant of salt marshes and similar coastal habitats in northern Europe, together with the
Black Sea and some saline places inland. It is now considered to be Vulnerable on a European scale,
as it has undergone considerable declines during the 20th Century. As a part of this decline, it was
believed to have become extinct in Britain during the 1930s, the last (and only 20* Century) records
coming from Walberswick, Suffolk (last seen 1938), Freiston, Lincolnshire (1932) and Pegwell
Bay, Kent (1924). Prior to that, it had been reported from at least 16 locations on the east coast, from
Lincolnshire to Kent, although there were no records from Essex (Leach 1988,1999).
Identification is straightforward (see Plate 10). Broad, elliptical leaves with a silvery-mealy appearance
demonstrate clearly its relationship with the widespread salt marsh sub-shrub Sea-purslane A.
portulacoides, but its non-woody nature and diminutive stature (less than 30cm tall in the wild) are
characteristic. As with most members of the Chenopodiaceae (Goosefoot family), its flowers are
greenish and relatively insignificant, that is until seed is set during early autumn. Then, the seeds are
surmounted by fleshy lobes, borne on long stalks (up to 3cm long in British material), giving an
appearance which is reminiscent of the heart-shaped seed pods of Shepherd's-purse Capsella bursa-
pastoris.
Its discovery in Essex
It was late September 1987. Just two weeks before the Great Storm swept through our woods, and
changed our view of woodland ecology for ever. This may not seem wholly appropriate to the
subject, but there are parallels with this story, as I shall return to later.
The England Field Unit of the former Nature Conservancy Council (NCC, now English Nature)
were surveying the Essex coast, with Simon Leach and Shaun Wolfe-Murphy making a complete
inventory of the botanical characteristics of our grazing marsh ditches. I was rather envious, tied to
the office, when one afternoon they returned in a state of not inconsiderable excitement. Envy turned
to incredulity and disbelief when they announced they had discovered a population of Annual Sea-
purslane, hidden away in a saline ditch near Southend, close to (but outside) the security fence of the
Ministry of Defence Foulness establishment.
Work programmes were hastily reorganised - obviously this was something we had to follow up.
First: see how many there were - a detailed count was conducted and revealed about 1700 plants,
patchily distributed around an area of some 10 square metres, associated with Common Saltmarsh-
grass Puccinellia maritima, Sea Aster Aster tripolium. Greater Sea-spurrey Spergularia media.
Essex Naturalist (New Series) 17 (2000)