to about 10%, the twigs mostly waste, except the one year growth. If I take a rough
figure, which I believe is generally accepted, that the firewood produced over a coppice
cycle is about a ton an acre a year, the smaller branches would be a little extra, the dried
leaves would be only a tiny fraction of this, the produce of the current year's growth. An
acre of grass would produce hay weighing between one and two tons, the total above
ground production, all of which is fed to livestock.
I heard the late John Hunter suggested parts of the Dengie Peninsula could have been
used to produce Elm feed for Roman cavalry horses on the continent. I have thought
veiy widely about this type of production, but cannot believe it was ever viable on a
large scale. 1 readily accept mature tree trunks were shredded every two or three years,
and the hedge which grew between them when they were planted on a boundary would
have been cut annually, unless livestock in the adjacent field had eaten the growth.
Looking at the Dengie Peninsula, it seems obvious Elm was used as a hedging material,
undoubtedly because Hawthorn, the best type, seems not to thrive well there. An Elm
hedge without management is no bar to livestock, because the straight single stem upright
growth will allow even mature cattle to walk through with ease. Today with modern
barbed wire secured on the growing trunks the cost and trouble of stakes is saved. Previous
livestock farmers would have found it essential to work a lot harder than just trimming
and occasionally laying a Hawthorn hedge. I take it for granted techniques were developed
whereby the trunk was partially cut about three feet high and bent parallel to the ground
and secured or supported by the next one, which was similarly treated, any gaps filled
by surplus trunks being used as post and rail fencing.
How many species are there at Hatfield Forest?
Stuart Warrington National Trust. Email: stuart.warrington@nationaltrust.org.uk
As members of the Essex Field Club know, Hatfield Forest is one of the most important
sites for nature conservation in the County. There are over 1000 acres of wood pasture,
coppice, grasslands and wetlands with a continuity of woodland and wood pasture
management going back well over 1000 years. To better understand the significance of
a site, it is invaluable to know what species inhabit it, and whether they are common,
scarce or rare in a national and county context.
However, a full species inventory of a site is a near impossible task. There are simply
too many species and too many different taxonomic groups. There is also the natural
change or turnover in species. Some species will inevitably become extinct in a location,
whilst others will colonise, so a species list will always be a snapshot in time. In addition,
the interpretation of a species list is not straightforward. The absence of species for
Essex Field Club Newsletter No. 50, May 2006
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