statistically valid) records. 1 have records of just over 160 oaks with girths over 15 ft. Of
these 136 arc pollards, 22 are standards and 3 are coppice stools. There are 52 trees
over 20ft. in girth, 14 over 25ft. in girth and 3 over 30ft in girth. I still have a few trees
to check there used to be a near 30 footer at Porters Hall, Stebbing but 1 have yet to
ascertain if it still survives. Importantly all but two of the oaks are Q. robur.... there is
however a huge Q. petraea pollard near Maldon (girth 22ft 7ins). My survey does
highlight how many ancient oaks are now lost to the county and the situation, because of
the lack of new pollards, is not going to get any better. One curiosity in Essex is the lack
of any sizeable Yew trees in our churchyards, which seems to be very much a western
and northern phenomenon in the UK.
I am hoping to transfer all my paper records onto Mapmate in the not too distant future
and I hope also to produce a map of what I know are or are likely to be, the best sites for
saproxylic invertebrates in the county. I am also working on a gazetteer of parkland sites
in the county .... this however is a mammoth task involving seemingly endless numbers
of such sites.
When measuring oaks in Essex a rule of thumb is that a tree with a girth of 15ft is
notable at county level, a girth of 20ft. plus is probably regionally important and a tree
with a girth of in excess of 25 ft. is nationally important (we have 14 such trees in
Essex). These figures may not apply to other counties since I suspect that other counties
may not have such a large population of sizeable trees. Where possible I am measuring
all oaks at 1.3m from ground level and also at 1.5m if it looks like a national champion,
but at another height if either the two previous girthings are not possible (e.g. because of
a lateral branch), always recording the height at which it was measured.
Any potential record trees, particularly oaks, to be added to the list would be very much
appreciated.
A note about rotifers: some very chaste organisms
Mary Smith 33 Gaynes Park Road, Upminster, Essex RM14 2HJ
If you find some dirty water lying around outdoors, perhaps a muddy puddle, any time of
year, and you put a drop or two onto a microscope slide, cover it, and view at about x 200,
you would be almost certain to find some rotifers. They are very common in water or
damp places, and contain around 1,000 cells in their bodies, which are mostly 200 -
500ϻm long, so they are only visible with a microscope. Although first seen by
Leeuwenhoek in 1703, many people are unaware of their existence, even though they are
so abundant Many species are able to dry up and stay alive for a long time in a shrunken
state, then regrow fast when water returns, so they can survive in a great variety of climates
and habitats. If you cannot see any for yourself, do put rotifer into Google and look up the
Essex Field Club Newsletter No. 50, May 2006
17