Skógræktarritið - 15.05.2001, Blaðsíða 100

been of fundamental importance
to the economy of such areas
where other land use options are
so restricted. In addition, wild
herbivores are also widespread
in these upland areas; those
which impact most widely on
trees are red and roe deer, but
more locally rabbits, hares and
small mammals such as voles
can have major impacts on
young trees. Red deer have tradi-
tionally been 'managed' for
shooting on the large estates of
Scotland and so their densities
can be as high as 30 per km2 in
some areas. These many years of
grazing have shaped the land-
scape dramatically, resulting in
large tracts of open ground.
Natural forest remnants are now
restricted to only about 3% of the
land area of Scotland, with per-
haps another 2% of montane
scrub (Mackenzie 1999; Hester
1995; Gilbert, this volume),
whereas estimates of how much
forest/scrub the land could actu-
ally support are close to 50% of
the land area (Towers, this vol-
ume). Within the large expanses
of open ground, these few
remaining natural forest areas
provide valuable shelter and
early grass growth for both sheep
and deer (Staines 1976; Grace &
Easterbee 1979), but often the
densities of wild and domestic
herbivores have been too high to
allow regenerating tree seedlings
to survive and grow, and many
hundreds of years of such heavy
grazing have had enormous
impacts on the state of the
remaining forested areas, with
many old trees and very few
young ones. Figure 1 shows an
area of the Cairngorms in the
Scottish Highlands where natural
forest cover is relatively high
(note the dense blocks of forest
are commercial plantations); the
natural woodland is mostly scat-
tered birch and pine.
Figure 1. View of the western
Cairngorm massif and part of the Spey
valley, Scottish highlands. Scattered
natural woodland (mainly birch and
pine) and conifer plantations are
visible.
The situation just described,
therefore, is one of conflicting
land uses, i.e. a severely deplet-
ed forest resource and large
numbers of free-ranging wild and
domestic herbivores for agricul-
ture and sporting purposes,
which are restricting new regen-
eration. This situation is com-
mon to several North Atlantic
countries. However, changes
have been taking place in the
past 10-20 years, with a gradual
increase in awareness of the
issue and the urgent need to
actively promote native forest
protection and expansion. In the
UK there is now considerable
effort aimed at redressing the
balance by actively encouraging
expansion of the native forest
area through natural regenera-
tion and planting schemes, many
of which are aided by
Government grants. In the last
five years, for example, establish-
ment of about 400 km2 of new
native forest has been grant-
aided (0.5% Scotland's land area)
(Mackenzie 1999). However, the
grants are still generally tied to
complete removal of large herbi-
vores by fencing, rather than the
development of policies which
combine reduced grazing with
regeneration, primarily because
large herbivore exclusion is still
perceived as the most reliable
way of letting young trees estab-
lish and grow into forest. Yet for
many reasons well described
elsewhere (e.g. cost, snow dam-
age, bird deaths, etc Hester
1995; Beaumont et al. 1995;
Gilbert, Horsefield & Thompson
1997), this is no longer consid-
ered the best solution and it is
now generally agreed that the
most desirable approach is not
to fence, but to control herbivore
numbers more sensitively, so as
to achieve forest regeneration
and grazing together (Hester &
Miller 1995).
Management needs
There are two fundamental needs
of a land manager wishing to
encourage forest expansion
whilst still grazing the land: (1)
first, they require practical guid-
ance on different densities and
species of herbivore required to
achieve whatever forest expan-
sion they want. All land man-
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SKÓGRÆKTARRITIÐ 2001 l.tbl.