The Scarce Plants of Essex. Part 2.
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marshes, grey dunes and sea walls. It also occurs, however, in non-brackish habitats, on dry banks and
waste ground, in the short turf of grazed grassland between the sea walls and borrow dykes, and in
maritime grazing marshes. It has a curious distribution in the U.K., being confined to England in an
area coincident with July temperatures in excess of 16°C and with its main centres in areas with the
highest summer temperatures; - along the Severn estuary, the Hampshire basin, around the Kent, Essex
and Suffolk coasts, and with a few scattered sites along the coasts of Norfolk and Lincolnshire north to
the Humber. It formerly occurred extensively inland but virtually all these sites are now gone, and it has
also lost ground along the south coast and in Suffolk, Norfolk, Cambs. and Lines. In Essex however it
seems to be maintaining its distribution, [although it has probably declined along the Thames estuary]
and has been recorded in 162 monads. See Map.
Bupleurum tenuissimum
Callitriche truncata ssp. occidentalis Guss
Short-leaved water-starwort
Essex status; New to Essex, spreading.
A rare native aquatic of southern England south of the 16°C July mean isotherm. Its main strongholds
are in the east midlands (Notts., Lines., and Leics.J where it has been recorded in 13 hectads, plus a
stable pocket in Somerset and a few scattered ephemeral records elsewhere. C. truncata lacks an
emergent rosette, and has small, (< 1.0cm) reddish-green leaves, and its mericarps are rounded on the
back with no trace of a keel. In common with C. hermaphroditica., it lacks the peculiar peltate hairs,
Essex Naturalist (New Series) 17 (2000)