147
The Scarce Plants of Essex. Part 2.
KEN ADAMS & 'TERRI TARPEY
Department of Life Sciences, University of East London E15 4LZ
'33 Bristol Road, Colchester COl 2YU
Abstract
The Essex status and distribution are given for the BSBI Scarce Plants: Bulbous foxtail, Marsh
mallow, Dense silky-bent, Loose silky-bent, Tower mustard, Slender hare's-ear, Short-leaved water-
starwort, Spreading bellflower, Divided sedge, Tufted sedge, Elongated sedge, Cornflower, Unarmed
or Soft hornwort, Chamomile, Saltmarsh goosefoot, Lesser Calamint, Sea-kale, Mossy Stonecrop,
Greater dodder, Galingale, Mezereon, Deptford pink and Maiden pink.
Introduction
The first six vascular plant taxa on the BSBI list of Scarce Plants in Britain, defined as those restricted
to 16-100 hectads in the UK (Stewart et al 1994), that occur, or have occurred in Essex, were dealt with
in the Essex Naturalist (New Series) (1999) 16: 101-109. The next twenty five species on the list are
considered below. Where taxa are difficult to identify, or inconspicuous and are therefore likely to be
overlooked, additional details have been provided to encourage the recording of these plants. As the
distribution details of the taxa on the list are published in this series, annual updates will be compiled
to keep the accounts up to date. The first of these updates is presented in this volume on page 146. The
authors would be grateful to receive additional site records and updates of occurrences in later years,
which will be kept as a website rolling file. The 1 x 1km sq. (monad) maps show the post 1930 records
that we have on file. Solid symbols localise to a monad, open symbols are only approximate locations,
and a + symbol following a grid reference indicates the central intersect of a tetrad.
Alopecurus bulbosus Gouan Bulbous foxtail
Essex Status; Native, possibly extinct.
This rare perennial grass is said to grow in damp, brackish, lightly grazed turf, rather than on salt
marsh, although it can survive periodic inundation by the sea, and is often associated with such species
as Carex divisa, Juncus gerardii and Trifolium fragiferum. Confined to England, it has been recorded
from 54 hectads post-1970, having disappeared from a further 32. Its a difficult grass to spot, as
although it often grows as a pure sward, and can be recognised by its swollen leaf bases, it lies dormant
for much of the year, with leaf growth from mid-April to July, flowering taking place from mid-May to
June [followed by rapid break up of the spikelets after seed set], and then it lies dormant until the
autumn, when it grows a new batch of leaves (Fitzgerald 1994). It is closely related to A. geniculatus,
with which it often grows and sometimes hybridises, but it is more upright and tufted, and has pointed,
as opposed to blunt glumes. It differs from Poa bulbosa, which also has swollen leaf bases, in its acute
as opposed to blunt ligule and persistent leaves. Those of P. bulbosa wither by about the end of April,
leaving the swollen bases to break off as propagules, whereas those of A. bulbosus serve as food stores
to regenerate the plants after the summer drought or marine inundation. It may be that it is still present
on some of our Essex grazing marshes, and we have yet to get our eye in for it. Its rediscover}' at East
Essex Naturalist (New Series) 17 (2000)