| Tayside Biodiversity - Tayside
Biodiversity Action Plan - Woodland - Upland Oakwoods |
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Wildcat (Felis
sylvestris)
Ecology - Wildcats have increased in both numbers and range
in Scotland in the past century and have benefited from afforestation.
The species is found mainly in upper valley slopes and steep
hillsides, on moorland and peatland and in rough grassland
or forest, as well as in the lowland margins. They have also
been recorded at higher altitudes, above 800m. It is listed
as a ‘Species of Conservation Concern’ in Tayside.
Distribution - Widespread, except in the lowlands in the
far east of Tayside. More abundant in Angus and east Perthshire.
In recent decades there has been little change in overall
range and the population in most areas appears stable. |
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There is a strong
understorey and structure associated with this woodland holding
a strong climax woodland community. Oakwoods and their associated
open areas provide a rich and diverse habitat for a variety
of invertebrates, including the Pearl-bordered fritillary Boloria
euphrosyne. A large proportion of species listed in the following
table are associated with the open ground areas of oakwoods.
KEY SPECIES
P = UK Priority species C = UK species of conservation concern
| Mammals |
Red squirrel |
Sciurus vulgaris |
P |
| Wildcat |
Felis sylvestris |
C |
| Badger |
Meles meles |
C |
| Brown long-eared bat |
Plecotus auritus |
C |
| Pipistrelle bat |
Pipstrellus pipstrellus |
C |
| Birds |
Wood warbler |
Phylloscopus sibilatrix |
C |
| Spotted flycatcher |
Muscicapa striata |
P |
| Redstart |
Phoenicurus phoenicurus |
C |
| Great spotted woodpecker |
Dendrocopus major |
C |
| Amphibian |
Great crested newt |
Triturus cristatus |
P |
| Invertebrates |
Pearl-bordered fritillary |
Boloria euphrosyne |
P |
| Hairy wood ant (Northern) |
Formica lugubris |
P |
| Higher Plants |
Wild hyacinth |
Hyacinthoides non-scripta |
C |
| Small cow-wheat |
Melampyrum sylvaticum |
P |
| Wilson’s Filmy Fern |
Hymenophyllum wilsonii |
C |
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NATIONAL
BIODIVERSITY CONTEXT
In the UK, upland semi-natural oakwoods have declined by about 30 - 40% in area
over the last sixty years as a result of replanting, mainly with introduced conifers,
clearance for quarries or other developments and conversion to rough grazings.
Recent changes have greatly reduced the amount of inappropriate management of
these woodlands.
The objectives of the UK Biodiversity Action Plan for Upland Oakwood are:
Maintain
the existing area of upland oakwood (70,000 - 100,000 ha.)
and improve its condition by a mixture of management for
timber (predominately as low intensity high forest), as
sheltered grazing and minimum intervention.
Avoiding other habitats of high nature conservation value,
expand the area of upland oakwood by about 10% on to currently
open ground by some planting, but particularly by natural
regeneration by 2005.
Identify and encourage the restoration of a similar area
of former upland oakwood that has been degraded by planting
with conifers or invasion by Rhododendron Rhododendron
ponticum. |
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In the context of
Scotland, the estimated area of all upland oakwoods is in the
region of 35,000 ha. of which ancient semi-natural woodland
(ASNW) accounts for 24,000 ha. The Scottish targets are to
initiate action in 80% of all HAP sites (i.e. 28,000 ha.) by
2004 and achieve favourable condition in over 50% by 2010.
Within these figures the target is to initiate action in 100%
of HAP sites occurring within SSSIs and SACs by 2004 and achieve
favourable condition in over 70% by 2010.
The restoration figures for upland oakwood in Scotland are 3,000 ha. by 2010.
This includes 10 ha. in Angus and 350 ha. in Perth & Kinross.
The expansion targets for upland oakwood in Scotland are 3,000 ha. by 2005. This
includes 110 ha. in Angus and 280 ha. in Perth & Kinross.
ECOLOGY AND MANAGEMENT
Sessile oak Quercus petrea and Downy birch Betula pubescens dominate this woodland
type. However where Quercus robur occurs, especially in eastern Scotland, it
is usually of planted origin. The lack of oak dominance in woodland on higher
slopes can often be attributed to past management and is not a true reflection
of the natural species composition of this woodland type. However with increased
altitude Birch becomes the dominant species. The field layer is dominated by
three types namely grasses, bracken and ericoid sub-shrubs. The relative proportions
of these vary with
soil type, shade, grazing and topography.
The oak woodlands are in general a mosaic of different NVC communities with W11
and W17 the major community types.
NVC
W11 This is the most common oceanic type of woodland
community with base-poor brown earth soils dominated
by Oak species and Downy birch Betula pubescens. Where
oak dominates, it forms a high forest with a closed canopy
of tall oak with poor crown development derived principally
from coppice and planted oak of unknown origin. Where
birch is more dominant the canopy is more open. The occasional
Ash Fraxinus excelsior may be found with, locally in
Tayside, Rowan Sorbus aucuparia and Hazel Corylus avellana
more common.
NVC W17 These communities
are less frequent than the W11, but these woodlands have
very acid shallow soils with Oak and Downy birch still
the dominant species. Where the oak is dominant the trees
are of a poorer quality and smaller than W11 oakwoods.
Where the Birch is more dominant, Rowan is present as
a co-dominant species. The commonest other species are
Holly Ilex aquifolium though generally quite scarce,
with Ash and Hazel which tend to be found in pockets
of base-rich wet flushes.
The cessation of coppicing and
the increased grazing pressure from both permitted grazing
of domestic animals and
browsing by wild animals has contributed to a decrease in the structural
diversity of this woodland type. It must be
pointed out that oakwoods that are not, or have never been, coppiced
are not necessarily biodiversity poor. The
removal of substantial amounts of timber throughout the early 20th
century also contributed significantly to the changing
composition and structure seen in Tayside’s upland oakwoods
today. |
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