Fen Management Handbook - Scottish Natural Heritage

Current Management
The current management of the site replicates the historical management and
tries to look at the site as a whole, rather than only the notified features, whilst
recognising that much of the management is a holding operation until the effect of
diffuse pollution in the catchment is resolved.
Fen cutting started in 1982. The species-rich fens are cut using a combination of
pedestrian mower/baler and small tractor with cut and collect facility. The vegetation
is cut in dry periods in August, dried where it is cut, collected and either burnt in
mobile incinerators or used for stock bedding. The grasslands of the islands are
cut in a similar manner leaving clumps of late flowering species for the benefit of
butterflies and moths such as the Scotch Argus and five-spot burnet moth.
Reed management. In the late 1980s it was becoming apparent that common
reed was expanding to the detriment of other fen communities, probably as result
of diffuse pollution and a reduction in grazing following notification of the mosses
in the 1970s. Since 1989, the reeds are cut, dried, collected and burnt in mobile
incinerators at the end of August and the ash removed from the site. The timing
of the cut coincides with the full extension of the reed and maximum development
of the inflorescence to maximise the amount of vegetation removed. The area cut
tends to be 30-40 m around the expanding edge of the reeds, which has checked
expansion of the reedbeds and increased plant diversity within the cut area from
three species of plant to around 25. Reeds still grow in the cut area, fed by the
rhizomes of the main bed, but their height and density has been substantially
reduced. In recent years to combat reed expansion in wetter areas inaccessible
to machinery, a strategy of herbicide treatment with glyphosate applied with a
weedwiper has been successful without negative impact on other vegetation.
Scrub and tree removal. Expanding birch scrub and trees were removed in the
early 1990s and herbicide treatment continues today. A strategy of targeting the
birch has paid off but in the early years the time input was high with some 30,000
birch seedlings removed from 0.1 ha alone in the summer of 1990. Regeneration
has diminished dramatically since the seed source trees were removed and
glyphosate treatment introduced.
Grazing. After a false start with stock being lost in deep open pools, grazing
was reinstated on an annual basis in the mid 1990s. Between September and
December, sheep are used to graze the regrowth following cutting. The fresh grass
of the cut areas focuses grazing away from the more dangerous water holes.
Rejuvenation of the hydrosere. From 1970s aerial photographs it was apparent
that the extent of open water on the sites was diminishing rapidly, to the detriment
of invertebrates such as darters and damselflies, and plants like bladderwort. A
programme of hand-digging small ponds was initiated in the early 1990s to partially
rectify the situation. This has been a success with rapid expansion of latent colonies
of bladderwort.
Catchment management. Many of the problems within the site are attributable to
wider catchment management, which despite being in an upland context has had
intensive arable and grassland culture. Designation as an Environmentally Sensitive
Area in 1993 allowed farmers to create buffer zones and cease fertilising fields
adjacent to the mosses. This has generally been a success in reducing inputs into
the mosses, but many of the fields adjacent to the moss are the best on the farm for
producing silage and consequently have not been included in ESA agreements.
Silt management. Silt high in phosphate is often washed into the burns and
creates silt fans on the mosses, which encourage the expansion of reeds and
terrestialisation. This is mainly a historical problem, partially resolved by fencing
burns from stock and the installation of in-stream silt traps. However the silt fans
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