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CLYDE VALLEY WOODLANDS |
(site map at base of page) |
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Total site
surface area (ha)
:504.7 ha
Status
: cSAC Other
protection status : The SAC
is comprised of the following SSSI: Avondale,
Cartland Craigs, Cleghorn Glen, Fiddlers Gill, Garrion Gill, Gills Burn
and Mares Gill, Hamilton High Parks, Jock’s Gill Wood, Nethan Gorge,
Townhead Burn and Upper Nethan Valley Woods. Parts of the Cleghorn Glen,
Cartland Craigs and Jock’s Gill sites form a Natural Nature Reserve
managed by Scottish Natural Heritage.
Hamilton High Parks is part of Chatelherault Country Park and
sections of Garrion Gill, Nethan Gorge and Upper Nethan Valley are
managed as wildlife reserves by an conservation NGO. Scientific
description of site
: The
Clyde Valley Woodlands pSCI supports semi-natural deciduous riverine and
gorge woodland. The deep gorges cut through calciferous old red
sandstone, with exposures of carboniferous limestone, overlain with
boulder clay. The woodlands are surviving remnants of ancient woodland with
trees which are a mix of age classes.
They are relatively undisturbed due to their inaccessibility for
timber extraction. The site
contains ash- elm woodland (Fraxinus
excelsior-Sorbus aucuparia-Mercurialis perennis woodland with Quercus robur-Pteridium aquilinum-Rubus fruticosus).
There are good examples of flush alder woodland (Alnus
glutinosa-Fraxinus excelsior-Lysimachia nemorum), and Cratoneuron
mats on tufa. The woodlands are important for invertebrates particularly
saproxylic invertebrates which depend on the considerable dead wood
habitat which has increased in recent years due to fallen and standing
elm (Ulmus glabra) which has
succumbed to Dutch Elm Disease. Open
areas, with mosaics of herb-rich grassland and scrub, are important
components of the site with species rich grasslands providing nectar
feeding sources for invertebrates and the scrub providing cover for
breeding bird communities. Importance
of the site for the conservation of the species/habitat types targeted
at regional, national and EU level : Threats: Threat 1:
Lack of management planning and background information Works
undertaken within the project need to be seen in the context of long
term conservation management and set within a formal management plan. In
the Clyde Valley there are a number of areas where management planning
will require that Management Agreements securing sensitive positive
management are negotiated between the landowner and the nature agency.
In one case a small unmanaged area is available for purchase on
behalf of a local environmental charitable organisation. Impact
on habitat Threat
2:
Lack of Integrated Management and Monitoring Location Impact
on habitat Threat 3: Displacement of understorey and groundflora by Rhododendron Rhododendron
Rhododendron ponticum is
present in small patches within the Clyde Valley Woods. The plant
spreads by seed and subsequently by vegetative layering and will coppice
from cut stumps. Once
established it can spread rapidly forming a dense canopy in the
understorey shading out native shrubs, groundflora and tree
regeneration. Location Impact
on habitat Threat 4: Displacement of native species by exotic broadleaved trees Exotic
broadleaved tree species such as sycamore, Acer
pseudoplatanus and beech Fagus
sylvatica have invaded and become established in all of the Clyde
Valley sites. Both species are shade bearing and compete well,
displacing native trees and shading out groundflora and understorey
species. The level of removal required differs from site to site and
ranges from complete eradication to a thinning of the exotic canopy
allowing native species to compete and regenerate. Location
Impact
on habitat Threat 5: Uncontrolled grazing by domestic stock The
Clyde Valley Woods are predominantly bounded by livestock farms and
deliberate or uncontrolled grazing by stock is a threat. Stock grazing
severely restricts regeneration of native tree and shrub species and can
significantly alter groundflora communities.
Grazing up to the boundary of existing woods restricts the
potential for expansion. Location Threat
7: Displacement or restriction of native woodland by planted exotic
coniferous woodland There
remains a legacy of previous forest policies which encouraged conifer
plantations within native woodland sites throughout the UK.
This ‘enrichment’ planting created dense plantations which
displace native trees, shade out native flora, alter soil conditions and
restrict woodland expansion. Conifer underplanting or planting on native
woodland sites contributes to the loss and fragmentation of woodland
habitat. Pockets of remnant
native trees and groundflora often exist which could contribute to the
regeneration of woodland habitat but such remnants may degrade the
longer the conifers remain. Location Impact Threat 8:
Displacement of native species by other exotic shrub species The
exotic shrub snowberry Synphoricarpus
albas forms thickets displacing native species and preventing their
regeneration. Location Impact
on habitat Threat 9:
Poor ground conditions for regeneration Where
woodland has been opened up by grazing or woodland degradation, dense
areas of bracken fern Pteridium
aquilinum have become established restricting the potential for
natural regeneration of other native tree and groundflora species. Location Impact
on habitat Threat
10:
Limited woodland structural diversity Some
of the sites have areas of limited structural and age-class diversity
caused by grazing, lack of management and invasion by rhododendron etc.
Without some intervention to open the canopy to promote
regeneration of diverse native tree and groundflora species and
understorey development, the achievement of favourable condition will be
delayed. Location Impact
on habitat Threat 11:
Lack of regeneration of native trees In
a few cases, even where measures such as thinning, protection from
grazing and ground preparation have been undertaken, the immediate
regeneration of native species can be limited losing the opportunity for
regeneration. Similarly on sites where expansion onto adjacent grazed
land is required, direct intervention by planting or protecting young
seedlings is warranted. Location Impact
on Habitat Threat
12:
Loss of non-woodland habitat diversity In
some areas in the Clyde Valley pSCI, native woodland habitats can
contain or grade into associated grasslands or scrub areas.
In positively managing the woodland habitat, steps must be taken
to ensure that existing important non-woodland habitat is maintained
where appropriate e.g. by maintaining grazing. Location Impact
on habitat Threat
14:
Fragmented, multiple woodland ownership The
Clyde Valley Woodlands pSCI includes 11 separate woodland areas and
these in turn may have a number of landowners often with very small
parcels of woodland under their ownership. Often landowners will have
little awareness of, or experience in woodland management. In order to
develop and effectively implement conservation management across the
site, considerable work is required to liaise with all stakeholders,
develop shared vision and objectives for site management and to contract
work efficiently. A project
officer is required and also liaison with local authority staff. Location Impact
on habitat This
threat is impacting on the whole site (504.7ha) Threat 15:
Rubbish and waste in woods Dumped
domestic waste and old disused fences in woodlands is a problem in some
woodland areas. Dumped
rubbish can cause pollution, attract pest species and detract from the
amenity and conservation value of the site.
Some forms of rubbish and old disused fences can directly
threaten wildlife. Threat
16:
Lack of widespread technical understanding and support Positive
management of Tilio-Acerion
sites for habitat conservation is relatively recent in Scotland. In
general, there remains a lack of formal technical understanding of
management practices and their impact on favourable condition in
differing contexts. Applied
research to develop technical guidance for restorative management is
proposed. Location Impact
on habitat Threat
17:
Lack of public awareness The
Clyde Valley Woodlands habitat is threatened by a general lack of
recognition of its conservation value and by the owners’ and
public’s limited understanding of what positive management can
entail. This impacts on the
level of financial and community support for conservation works and
reduces scope for habitat management beyond the pSCI sites.
Interpretation and promotion and associated activities are
required. Location Impact
on habitat
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