CHOBHAM COMMON NNR - Surrey Wildlife Trust

Light grazing can compensate for annual nitrogen in/outs (Fottner et al., 2007). On
heathland in south east England, grazing might approximately balance the annual
input of nitrogen but further action would be needed to reduce the stored nitrogen
from previous inputs
A decrease in plant richness in wet heath and valley mires has been correlated with
an increase in Molinia cover following cessation of grazing (and vice versa) over time
scales varying between three and 40 years in Pembrokeshire, the New Forest and
Dorset (Byfield & Pearman, 1994; Chatters, 1996; Clarke, 1988; Cox, 1998; Evans,
1989; Lake, 2002). For example, Cox (1998) and Lake (2002) showed an increase in
characteristic mire species such as bog asphodel Narthecium ossifragum, oblongleaved
sundew Drosera intermedia, round-leaved sundew Drosera rotundifolia,
cotton grass Eriophorum angustifolium and some Sphagnum species, together with a
decrease in purple moor grass and dwarf gorse Ulex minor, after three years of
moderate grazing. This is corroborated by (Clarke, 1988) and (Sanderson, 1994)
where higher diversity in grazed areas was seen in the bryophyte, sedge and herb
communities.
The use of grazing requires the control of stock. If sheep are used, then control may
be through shepherding or fencing, but cattle or ponies will require fencing.
Sheep
The continental sites grazed by shepherds consist of a mixture of heathland,
grassland and arable. The sheep are taken onto the heaths by a shepherd, who
stays with them all day and controls them with trained dogs. Dogs are usually large,
intelligent and can be well trained, and can guard against other dogs chasing sheep.
In the late afternoon the sheep are taken off the heath and folded for the night into a
barn. This system operates for 365 days pa, except during lambing in early spring
when the sheep are kept on lay-back grassland. The shepherds and their flock are
an attraction to both the local people and tourists, but tend to operate in areas where
the numbers of other users are low, where dog walkers have to keep their dogs on
leads, and where there are very large open spaces. Each shepherd looks after a
flock of about 400 ewes, with 50 wethers, 6-8 rams and 350 lambs. Sheep are
ineffective graziers of tall vegetation such a Molinia but could be used after controlled
fires or cutting. On sites where Molinia is dominant, as it is green only during the
summer, (or where only summer grazing is required) this type of shepherded system
would not be appropriate. If sheep are fenced in, then sheep netting must be used
which is more expensive to install than normal stock fencing, and some protection
against dogs is essential.
Goats
Goats are unsuitable for large areas as they are the most difficult stock type to
contain and would be vulnerable to attack by dogs. Where contained in small
enclosures for a specific task, goats can be a useful way of managing vegetation,
particularly growth of young trees and shrubs as they are browsers rather than
grazers. Large scale use of goats on Chobham Common as a management
mechanism would not be practical.
Cattle and ponies
Cattle and ponies require fencing and breeds must be carefully chosen. Traditional
breeds are generally docile and ignore dogs and people. Cattle grazing takes place
on many heavily visited sites, but despite this, many visitors are understandably
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