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Saltmarsh Goosefoot at Old Hall Marshes
TERRI TARPEY
33 Bristol Road, Colchester, Essex COl 2YU
Introduction
The Colchester Natural History Society (CNHS) is undertaking a long-term wildlife survey of Old
Hall Marshes for the Royal Society for Protection of Birds. Saltmarsh Goosefoot occurs on the
reserve, and in 1997 a full survey was carried out of its distribution and frequency. The initial
findings were published in Nature in North East Essex (CNHS 1999), much of which is reproduced
below, along with results from subsequent survey in one particular area of the reserve.
Saltmarsh Goosefoot Chenopodium chenopodioides (L.) Aellen, previously named Small Red
Goosefoot Chenopodium botryod.es Sm., has the status of 'rare' in Britain (JNCC 1994). It is an
annual, growing on the seasonally-exposed, muddy margins of Saltmarsh ditches, creeks and fleets.
It resembles a small (to 30 cm), usually much branched, and procumbent to ascending Red Goosefoot
C. rubrum, but only the basal lobes of the triangular leaves are well developed. A diagnostic feature
is the perianth - the tepals of the lateral fruits are fused to near the apex, as opposed to fused less
than halfway in Red Goosefoot, with which it is most likely to be confused. The restricted habitat
and exacting requirements make Saltmarsh Goosefoot a vulnerable and threatened species.
In the past it has been recorded in 23 hectads (10 km squares) on the south and east coasts of
England from Hampshire to south Lincolnshire, with its main stronghold in Essex and north Kent.
Post-1970 records (12 hectads) show its range has contracted to the Essex and north Kent marshes,
with the odd outlier in south Kent and Suffolk. The Atlas of the Kent Flora shows 21 tetrads (Philp
1982) and since then it has been recorded from a further 12 tetrads, the plant thriving along the
edges of brackish dykes on the bare mud exposed in dry summers (Eric Philp pers. comm.). Of these
33 tetrads, 32 arc on the north Kent marshes with only one in the south of the county. The latest
record for Suffolk is dated 1974, from Frostcnden, and is considered unlikely still to be present
(Martin Sanford pers. comm.). However, there is still plenty of suitable habitat in the county. First
recorded in Britain from Gt Yarmouth in 1811, the four other records for Norfolk are all credited to
Kirby Trimmer, author of the first Flora ofNorfolkin 1866. There have been no records since (Alec
Bull pers. comm.).
Gibson (1862) lists six sites for Essex but implies possible confusion between this species and Red
Goosefoot Jermyn (1974) considered the plant to be rare in the county and gives nine sites in five
hectads from the Thames marshes north to Mersea Island. The plant was not found during the survey of
north-east Essex (Tarpey & Heath 1990) but has since been found at Old Hall Marshes National Nature
Reserve, Tollesbury. Since the publication of Jermyn's Flora of Essex in 1974, Saltmarsh Goosefoot has
been recorded at eleven sites in the county, all but one along the Thames Estuary: Hadleigh Marshes
(1979); Tilbury (1983); Two Tree Island(1985); Canvey Island(1990); Leigh on Sea (1992); Vange and
Pitsea Marshes (1996), East Tilbury Marshes (1997); Hyde Marsh (1997); Fleet Head (1997); Bowers
Gifford Marshes (1998) (Ken Adams pers, comm.) and Old Hall Marshes (1990-1999).
None of the earlier records mentioned Old Hall Marshes, where it is now common in places; with
the habitat having remained as grazing marshes, it is likely that it has been overlooked in the past.
In order to determine its exact distribution and abundance at Old Hall Marshes, I carried out a
survey during 1997. Saltmarsh Goosefoot is a late flowering species and the survey was carried out
on five days between 22 August and 8 September 1997.
Essex Naturalist (New Series) 17 (2000)