As for Upper Goldings Hill Pond, it is not looking good. By the spring of 2004 a bright
green lawn of Crassula helmsii had covered the floor of the northwest bay, and small
patches had appeared around the margins in areas they had not occurred before. In
addition during late 2003 some so and so had introduced quite a large quantity of
Myriophyllum aquaticum, and despite several efforts to remove it all, by the spring of
2004 it appeared to be well established right across the pond. There has got to be some
other way of clearing aliens from ponds. In addition to the species mentioned above, as
a result of the scouring we have probably lost the duckweed Spiro Delia polyrhiza (now
very rare in Essex), the floating liverworts Ricciocarpos natans and Riccia fluitans, and
the BSBI scarce grass Alopecurus aequalis. The Bladderwort this year has kept a low
profile without any flowers - maybe it used up all the water fleas!
Common Bladderwort has been recorded from several ponds on Epping Forest, namely:
Lesser Wake Valley (east and west), Wake Valley Bomb Crater, Wake Valley Pond, Oak
(small) Pond, High Beach, Strawberry Hill Gravel Workings, Wake Arms Gravel Work-
ings (just south of Wake Arms), Baldwins Hill Pond, Upper Goldings Hill Pond, Long
Running Bomb Crater Pond, and the Lost Pond. In the Lost Pond, it is now so prolific
that it blankets the shallows smothering everything else, and is possibly the reason that
the Water Violet Hottonia palustris has been extinct there for some years - once re-
garded by us as its locus classicus.
In 1988 when the water was at a low ebb, I discovered a large colony of U. australis
(with one flower) in the SE corner of the Perch Pond in Wanstead Park, but have not
seen it there since. In 2002 David Corke sent me a specimen from his garden pond at
Wimbish, fed by rainwater from his roof. That turned out to be the same species, which
he thinks must have arrived on its own. Apart from that I have a recollection of an old
record in a pond on Coppersale Common, but can't think where I got it from! There is
also an authenticated specimen collected at Broomfield in 1838.
U. australis seems to be doing particularly well on Epping Forest at the moment, not
only spreading to new ponds, but growing very prolifically It might well therefore ap-
pear in other parts of the county - so please keep a look out for it (and the next species)
and send me any records. Look for a pale yellowish green fluffy plant with a character-
istic zigzag branching - and of course water flea trapping bladders that turn from green
to black and swell in size on capturing a victim.
We have one recent record for the County presumed to be of U. vulgaris s.s. the Greater
Bladderwort. This occurs in brackish coastal marshes in Suffolk, so it was not that unex-
pected for Douglas Kite to find it in the Wennington Branch Sewer on Wennington
Marshes in 1985 during the grazing marshes survey. It has not however been seen since.
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Essex Field Club Newsletter No. 45, September 2004