Habitat account - Forests


91A0 Old sessile oak woods with Ilex and Blechnum in the British Isles 

Background to selection

Distribution of SACs/SCIs/cSACs with habitat 91A0 Old sessile oak woods with Ilex and Blechnum in the British Isles.  Click image for enlarged map.
Distribution of SACs/SCIs/cSACs with habitat 91A0 Old sessile oak woods with Ilex and Blechnum in the British Isles. Click image for enlarged map.

Description and ecological characteristics

 

This habitat type comprises a range of woodland types dominated by mixtures of oak (Quercus robur and/or Q. petraea) and birch (Betula pendula and/or B. pubescens). It is characteristic of base-poor soils in areas of at least moderately high rainfall in northern and western parts of the UK.

 

The habitat corresponds broadly to the ‘western oakwoods’ described in previous accounts of UK woodlands, particularly NVC types:

 

     

  • W10e  Quercus robur – Pteridium aquilinum – Rubus fruticosus woodland, Acer pseudoplatanus – Oxalis acetosella sub-community
  • W11  Quercus petraea – Betula pubescens – Oxalis acetosella woodland
  • W16b Quercus spp. – Betula spp. – Deschampsia flexuosa woodland, Vaccinium myrtillus – Dryopteris dilatata sub-community
  • W17  Quercus petraea – Betula pubescens – Dicranum majus woodland

 

The habitat shows considerable variation across its range, in terms of the associated ground flora and the richness of bryophyte communities. There is also a continuous spectrum of variation between oak-dominated and birch-dominated stands. Often these local variations reflect factors such as rainfall, slope, aspect, soil depth, and past and present woodland management (e.g. coppicing, planting, grazing). The most distinctive forms of the habitat have a ground flora dominated by bryophytes, such as Dicranum majus, Hylocomium splendens, Isothecium myosuroides, Plagiothecium undulatum, Rhytidiadelphus loreus, Bazzania trilobata and Plagiochila spinulosa. Other variants include stands in which the ground flora is characterised by the prominence of dwarf shrubs, such as bilberry Vaccinium myrtillus; grasses, such as wavy hair-grass Deschampsia flexuosa, common bent Agrostis capillaris and sweet vernal-grass Anthoxanthum odoratum; and plants indicative of more mesophytic conditions, including bluebell Hyacinthoides non-scripta, bramble Rubus fruticosus, scaly male-fern Dryopteris affinis.

 

Birch-dominated woodlands which contain at least some oak, and which either (a) occur as part of an intimate mosaic with oak-dominated stands, or (b) are clearly successional stages which are reverting to oak woodland, are included in the Annex I definition. However, birch woodlands in Scotland which lie beyond the present-day natural distribution of oak, and also those within this range for which there is no historical evidence for the presence of oak, are excluded from the Annex I type.

 

Frequently the oak woodland occurs as part of a mosaic of woodland types (including other Annex I habitats, such as 9180 Tilio-Acerion forests of slopes, screes and ravines and 91E0 Alluvial forests with Alnus glutinosa and Fraxinus excelsior (Alno-Padion, Alnion incanae, Salicion albae)) that varies with position on the slope, occurrence of streams or other waterbodies, and local soil enrichment. These transitions are important in maintaining the structure and function of the habitat type and differ across the country.

 

A key feature of European importance is the rich Atlantic bryophyte communities that are often well-developed within this Annex I type. These include numerous rare species, such as Campylopus setifolius, Sematophyllum demissum, Adelanthus decipiens, Leptoscyphus cuneifolius and Plagiochila atlantica. Fourteen different bryophyte zones have been identified in the UK (Ratcliffe 1968), with distinct differences in the bryophyte assemblages within them. The richest zones are in the western Scottish Highlands. Stands of old sessile oak woods in eastern Britain tend to be much smaller and less distinctive in their species composition, particularly their bryophyte assemblages.

 

In addition to the bryophyte zones, there are distinct differences in higher plant and animal assemblages in the south compared with the north. Some woodlands hold rich lichen floras, especially epiphytic assemblages such as the Lobarion community.

European status and distribution

 

Within the EU, old sessile oak woods with holly Ilex aquifolium and hard-ferns Blechnum spp. are virtually confined to the UK and Ireland. It is possible that similar stands could occur in north-west Iberia and Brittany.

UK status and distribution Click to view UK distribution of this habitat

 

Old sessile oak woods are widespread and locally extensive throughout the western part of the UK. They are much more thinly distributed in drier eastern regions.

Site selection rationale

 

Sites have been selected to reflect the geographical range and ecological variation in the type, giving particular weight to the exceptional bryophyte communities that reach their finest development in western Scotland. Selection has also taken account of the fact that the UK has particular responsibilities for conserving this habitat type, as it holds a high proportion of the total EU resource. A large number of sites have therefore been proposed, and the SAC series contains a large proportion of the high-quality examples of the habitat.

 

Much of the extant oakwood resource in the UK is fragmentary, and has been substantially modified by human activity. Therefore the largest remnant examples of qualifying habitat have been favoured when identifying SACs. Adjacent woodland blocks have often been grouped into clusters in the process of site selection to take account of the formerly more extensive and more continuous cover of this habitat type. Many of the unselected woodlands are small, fragmentary, or floristically impoverished, and are not considered to be of European importance. Outside the SAC series, protection of Atlantic oak woods is provided by the SSSI mechanism, the UK Biodiversity Action Plan and other wider countryside measures.

 

The fragmentary nature of the habitat is reflected in the relatively large number of sites where old sessile oak woods are a qualifying feature, but not a primary reason for site selection.


Site accounts

Ardvar and Loch a' Mhuilinn Woodlands Highlands and Islands
This complex of woods represents old sessile oak woods at the extreme north of its range in Scotland. The site includes the extensive and diverse Ardvar Woodlands, which are mainly birch-dominated with oak throughout, and the woodland at Loch a’Mhuilinn, the other component of this complex, to the north, which has small areas dominated by oak. The area of woodland at Loch a’Mhuilinn lies on the north-west coast of Sutherland near sea level where the effects of exposure on the growth form of some of the oaks are particularly well-demonstrated. The oaks are of special interest because they are the most northern remnant of native oak woodland in the British Isles. Both sites are very important rich oceanic bryophyte sites with good examples of the macrolichen Lobarion community.
Banagher Glen Northern Ireland
Banagher Glen in the foothills of the Sperrin Mountains is one of the largest and least disturbed examples of old sessile oak woods in Northern Ireland. The site has a long history of continuous woodland cover, and has a well-developed structure with a range of different layers present. The naturalness of the wood is exemplified by the low number of non-native species and the relative abundance of old trees and epiphytes. The acid woodland flora is characterised by a canopy of sessile oak Quercus petraea and occasional downy birch Betula pubescens, with a ground flora of grasses, including wavy hair-grass Deschampsia flexuosa, and calcifuge mosses such as Rhytidiadelphus loreus. Where grazing is absent, bilberry Vaccinium myrtillus is dominant. Where conditions are rather less acidic, hazel Corylus avellana is occasional in the shrub layer, with great wood-rush Luzula sylvatica and bluebell Hyacinthoides non-scripta in the ground flora. The wood contains a rich variety of plants and includes a number of notable bryophytes and lichens.
Blackmill Woodlands East Wales
Blackmill Woodlands is an example of old sessile oak woods at the southern extreme of the habitat’s range in Wales, and contributes to representation of the habitat in Wales and in south-west England. The ground flora is restricted by the relative dryness of the site, but the main habitat features of sessile oak Quercus petraea canopy, acidic ground flora of Vaccinium myrtillus and wavy hair-grass Deschampsia flexuosa, and moderate fern and bryophyte cover are present. The woodlands have a long cultural history of management, reflected in the distinctive gnarled appearance of many of the trees.
Borrowdale Woodland Complex Cumbria
Borrowdale has the most extensive block of western old sessile oak woods in northern England, and has a diverse range of stand types, which contributes to conservation of habitat structure and function. Amongst the oak stands there are small patches of 91D0 Bog woodland (birch Betula sp. on peat), ash Fraxinus excelsior woodland and alder Alnus glutinosa stands. The woods are especially rich in bryophytes and lichens, and northern species occur, such as the moss Ptilium crista-castrensis. Rare plants, such as touch-me-not balsam Impatiens noli-tangere and alpine enchanter’s-nightshade Circaea alpina, also have important British occurrences here.
Breen Wood Northern Ireland
Breen Wood is one of the best examples of old sessile oak woods in Northern Ireland. It is traversed by glacial outflow channels that have formed a series of dry, low ridges interspersed by damp, narrow valleys. Over these freely-draining and leached slopes, the wood is strongly calcifugous in nature, with a high canopy of downy birch Betula pubescens and oak Quercus spp. The shrub layer is composed of rowan Sorbus aucuparia with some holly Ilex aquifolium. The field layer is dominated by bilberry Vaccinium myrtillus, with occasional bramble Rubus fruticosus agg., honeysuckle Lonicera periclymenum and ferns, typically bracken Pteridium aquilinum. The herb layer is overwhelmingly dominated by extensive carpets of great wood-rush Luzula sylvatica. The only other species that occur to any significant extent are hard fern Blechnum spicant and wood-sorrel Oxalis acetosella. Breen Wood is the only known location in Northern Ireland for the moss Hylocomium umbratum.
Calf Hill and Cragg Woods Lancashire
These old sessile oak woods occupy north- and south-facing slopes of a valley on millstone grit. Oak dominates in the canopy with birch Betula sp., rowan Sorbus aucuparia and holly Ilex aquifolium. The ground flora ranges from areas of abundant bilberry Vaccinium myrtillus, through grassy areas, to rich moss carpets. Small areas of alder Alnus glutinosa flushes also occur.
Cawdor Wood Highlands and Islands
This site is one of the largest oak woodland sites in north-east Scotland, and is important within the SAC series as it represents the more continental end of the habitat range. The wood is outstanding for its lichen flora, with species characteristic of relatively dry ‘continental’ climatic conditions. The ground flora is also characteristic of more continental stands, dominated largely by great wood-rush Luzula sylvatica and heather Calluna vulgaris.
Coedydd a Cheunant Rheidol/ Rheidol Woods and Gorge West Wales and The Valleys
Rheidol Woods provides a very large example of old sessile oak woods in mid-western Wales, extending along a steep-sided river valley. The canopy is dominated by sessile oak Quercus petraea, and the ground flora has the typical acidophile species and well-developed lower plant component of this habitat in Wales. Small-leaved lime Tilia cordata occurs in places, suggesting a fragmentary occurrence of 9180 Tilio-Acerion woodland. The woods are also notable for breeding birds.
Coedydd Aber West Wales and The Valleys
Coedydd Aber is the largest continuous area of old sessile oak wood along the north Wales coast, and gives geographic representation of the habitat between the large examples further south in Wales, and those to the north in Cumbria. The main woodland extends along a valley, rising steeply from near sea level. The canopy consists largely of sessile oak Quercus petraea and downy birch Betula pubescens, but there are intricate transitions to ash Fraxinus excelsior woodland and extensive areas of alder Alnus glutinosa woodland. The ground flora is diverse, reflecting complex edaphic and management variations. There is a rich lower-plant flora, including the rare mosses Fissidens rufulus and Philonotis rigida, and the lichens Degelia plumbea and Lobaria amplissima. The site is also important for its breeding bird assemblage.
Coedydd Derw a Safleoedd Ystlumod Meirion/ Meirionnydd Oakwoods and Bat Sites West Wales and The Valleys
Meirionnydd Oakwoods are a very large example of old sessile oak woods in north Wales, with an outstanding Atlantic flora of bryophytes and lichens. Notable bryophyte species include the endangered Sematophyllum demissum and the nationally scarce Campylopus setifolius and Leptoscyphus cuneifolius. The woods – primarily of sessile oak Quercus petraea with an acidic ground flora – extend along a series of inter-connected valleys, with a wide variety of slopes and aspects, and include many narrow ravines and gorges. Management is diverse, including grazed and ungrazed areas, and stands managed silviculturally, or as minimum intervention. This wide range of environmental, topographic and management conditions contributes to the high biological diversity of this exceptional site. The woods extend into the adjacent Rhinog cSAC.
Coedydd Llawr-y-glyn East Wales
Coedydd Llawr-y-glyn is one of several sites representing old sessile oak woodland in the core of its Welsh range. It comprises a group of woodland blocks set around a series of connected valleys. The woods are primarily of sessile oak Quercus petraea with a typical acidic ground flora of bilberry Vaccinium myrtillus, wavy hair-grass Deschampsia flexuosa and abundant bryophytes. However, there is much local variation in woodland structure and floristics. Notable species include oak fern Gymnocarpium dryopteris, beech fern Phegopteris connectilis and the lichen Thelotrema lepodinum. The site also has an outstanding bird assemblage.
Coedydd Nedd a Mellte East Wales
Coedydd Nedd a Mellte is a very large and diverse example of old sessile oak wood in south Wales. The woods extend along a series of deeply incised valleys and ravines, and contain complex mosaics of sessile oak Quercus petraea woodland, ash Fraxinus excelsior woodland (some of which is referable to Annex I type 9180 Tilio-Acerion forests of slopes, screes and ravines), and transitions to lowland woodland types. The whole site is biologically rich, with many woodland plant communities represented and rich bryophyte and lichen assemblages. Notable higher plant species include wood fescue Festuca altissima and the ferns Dryopteris aemula, Hymenophyllum tunbrigense and Asplenium viride.
Coetiroedd Cwm Elan/ Elan Valley Woodlands East Wales
Elan Valley Woodlands is one of several sites representing old sessile oak wood in central Wales. The site is extensive, and comprises a series of woodland blocks with varying topography and underlying geology, and a wide range of structural types from dense closed canopy to open wood pasture with ancient trees, which support a rich invertebrate fauna. Sessile oak Quercus petraea predominates, with a typical upland acidic flora and rich lower plant assemblages including bryophytes such as Bazzania trilobata, Plagiochila spinulosa and Saccogyna viticulosa, and the lichens Arthonia vinosa, Catillera sphaeroides and Thelotrema lepadinum. The woods are also notable for their bird-life. They are all Special Protection Areas, and support breeding red kites Milvus milvus.
Coille Mhor Highlands and Islands
Coille Mhór is an example of old sessile oak woods in north-west Scotland. Within the woodland, oak dominates the lower, more southerly-facing slopes of the site with birch stands on the higher ground and on steep screes and crags. Ash, rowan, alder, willows and hazel are also present. Many of the oaks on this site are veterans which are now growing within an infilled wood-pasture which is regenerating as woodland. The mature woodland is lichen-rich with six rarities and some species are at their northernmost limit.
Cwm Doethie - Mynydd Mallaen West Wales and The Valleys
Cwm Doethie – Mynydd Mallaen contains a large area of old sessile oak wood along a series of inter-connected valleys. The site is one of several examples representing this habitat in the core of its Welsh range. Sessile oak Quercus petraea woodland predominates, with a typical acidic ground flora and rich lower plant component. The site is also notable for its upland heathland and grassland communities, and for its breeding bird assemblages, which includes red kite Milvus milvus.
Dartmoor Devon
Three main areas of oak woodland are included within this site. Wistman’s Wood is notable as a high-altitude relict surviving on a granite clitter slope. Unusually for old oak woods in the UK, it is dominated by pedunculate oak Quercus robur rather than sessile oak Q. petraea. The epiphytic and ground-covering bryophyte flora, with filmy ferns, is species-rich, although there are some indications that some species may have declined in recent years, possibly because as the tree canopy has grown conditions below it have become less humid. Wistman’s Wood has a well-documented record of changes over the last century.

Dendles Wood is dominated by pedunculate oak Q. robur, but with substantial areas of beech Fagus sylvatica on the lower slopes (considered to be a possible outlier of the native range of beech). The ground flora is a mixture of grasses, bracken Pteridium aquilinum, bluebell Hyacinthoides non-scripta, with locally many boulders supporting a species-rich bryophyte mat. There is a luxuriant epiphytic lichen flora including several rare species. Although selected for its oakwood community, the beechwood is a fragmentary outlier of Ilicio–Fagion.

Black Tor Copse has similarities to Wistman’s Wood, consisting of stunted trees developed on granite clitter. The vascular plant species-richness is limited, with much bilberry Vaccinium myrtillus, hard-fern Blechnum spicant and ivy Hedera helix, but the bryophyte and lichen assemblages are very rich including nationally-rare species and others seldom found outside the uplands of Scotland and Wales.
Dinnet Oakwood North Eastern Scotland
Dinnet Oakwood is one of two sites representing the Eastern Highlands Atlantic Bryophyte zone. There are few examples of oak woodland in north-east Scotland as the habitat is more fragmented than in the west, and although Dinnet Oakwood is relatively small, it contains regionally important stands of old sessile oak wood. Partly, or even wholly, the product of plantings in the early 19th century, Dinnet Oakwood retains the character of a relatively undisturbed semi-natural northern oakwood. Ground flora characteristic of the habitat occurs, with northern species such as intermediate wintergreen Pyrola media and chickweed wintergreen Trientalis europaea. Stone bramble Rubus saxatilis and wood cow-wheat Melampyrum sylvaticum also occur. The fungus flora of the wood is of national importance and contains several rare species dependent on oak and charcoal.
Exmoor and Quantock Oakwoods Devon, Dorset and Somerset
This site supports extensive tracts of old sessile oak woods in conjunction with heath. They are rich in bryophytes, ferns (including Dryopteris aemula) and epiphytic lichens, the latter often associated with old pollards, since parts are former wood-pasture rather than the oak coppice that is more common with this type. In the Barle Valley the woods also occur in mosaic with glades and small fields and the combination results in good populations of fritillary butterflies.
Galloway Oakwoods South Western Scotland
This complex of oakwoods is the only site within the SAC series representing the South-west Lowlands of Scotland Atlantic Bryophyte zone. The individual sites are small and dispersed, but are regionally important due to the highly fragmented nature of remnant semi-natural woodland in south-west Scotland. The complex contains good examples of old sessile oak woods, some of which have been coppiced in the past, with a notable oceanic bryophyte flora, including some species rare in south-west Scotland. They typically have rich assemblages of Atlantic mosses and liverworts, lichen communities and ferns, such as hard fern Blechnum spicant. Holly Ilex aquifolium is common in the understorey.
Glen Beasdale Highlands and Islands
Glen Beasdale is one of the largest oakwoods in Lochaber. It is an extensive area of coastal old sessile oak wood on acid soils, derived from Moine rocks, and has a healthy ground cover with heather Calluna vulgaris and purple moor-grass Molinia caerulea. Moving inland, there are transitions to more birch-dominated areas at higher altitude. The bryophyte flora is rich and includes several species with an Atlantic distribution. A diverse lichen flora is also present. The woodland at Glen Beasdale is ecologically distinct from comparable oakwoods at Loch Moidart (within the Loch Moidart and Shiel Woods site), where the vegetation is influenced by base-rich rock outcrops.
Glen Creran Woods Highlands and Islands
This complex of sites in north Argyll represents old sessile oak woods in the west of Scotland. Some of the component sites also contain examples of 9180 Tilio-Acerion forests of slopes, screes and ravines. The woodland is of outstanding importance for the rich communities of mosses and lichens which it supports.
Glen Shira Highlands and Islands
Glen Shira is located at the northern end of a typical U-shaped valley on a south-east – north-west axis, rising from sea level to above 500 m. The site contains habitat representative of old sessile oak woods with Ilex and Blechnum. The site comprises two distinct blocks of oak wood, separated by the River Shira and associated areas of open and grazed ground which are excluded from the site. The orientation of the valley means that the woodland is situated on both north-west and south-east facing slopes, which has encouraged the development of greater diversity. The qualifying oakwood habitat in the western part of the site is interspersed with areas of non-qualifying alder–ash woodland and patches of open ground where regeneration is occurring. The eastern block consists almost entirely of qualifying old sessile oak wood, mainly oak-dominated, with alder Alnus glutinosa, ash Fraxinus excelsior and hazel Corylus avellana also present. The main NVC types representing old sessile oak woods across the site are W11 and W17. The woods support an outstanding assemblage of bryophytes, including both oceanic ‘Atlantic’ types and calcicolous species. Glen Shira as a whole is considered to be one of the richest woodland bryophyte sites in Scotland, with 128 species recorded within the western block alone, of which 27 are Atlantic species.
Kinloch and Kyleakin Hills Highlands and Islands
This is an extensive upland site on Torridonian Sandstone, where the lower slopes contain several areas of rocky woodland and wooded ravines varying from acidic oak–birch QuercusBetula woodland, to base-rich ash–hazel Fraxinus excelsiorCorylus avellana woodland with a herb-rich ground flora. It includes the woodland at Leitre Fura, one of the few woods on Skye which is dominated by ash and wych elm Ulmus glabra. Many of the oak and ash trees within the component woods of this site are veterans and are now growing within an infilled wood pasture, which has regenerated as woodland. Several of the component woods support a very rich bryophyte flora, both as epiphytes and on the block scree within the wood, with an internationally important representation of oceanic species, especially in ravines deeply cut into the sandstone. The woods are also important for epiphytic lichens, with good examples of euoceanic communities.
Lake District High Fells Cumbria
This site includes Side Wood, Ennerdale, an example of old sessile oak woods with rich bryophyte and lichen communities. There are large tussocks of the moss Polytrichum strictum mixed with bog-moss Sphagnum spp. Birkrigg and Keskadale Oaks and Young Wood are also included within the site. These are on steep south-facing slopes near the altitudinal limit for oak in Cumbria. In Birkrigg and Keskadale bryophytes and lichens are abundant and include species such as Hedwigia integrifolia. Birk Fell also includes substantial areas of bryophyte- and fern-rich oak woodland. Notable bryophyte species include Breutelia chrysocoma, Saccogyna viticulosa and Pleurozia purpurea. Fragments of this habitat also occur elsewhere throughout the site, mostly in gills or other areas less accessible to grazing animals.
Largalinny Northern Ireland
Largalinny represents bryophyte-rich old sessile oak woods in Northern Ireland. The site contains mixed deciduous woodland in which western oakwood predominates, but there are also flushes and calcicolous woodland, and there is a transition to open heath. A number of rare species, such as serrated wintergreen Orthilia secunda and the oceanic Tunbridge filmy-fern Hymenophyllum tunbrigense, are found here, as well as a rich bryophyte and lichen flora.
Ledmore Wood Highlands and Islands
Ledmore Wood represents old sessile oak woods in north-east Scotland. This is the largest oak-dominated wood in Sutherland, and the most northerly large oakwood in eastern Britain. The wood is dominated over most of its area by oak Quercus spp., but gives way higher up to mature birch Betula spp. wood with patches of juniper Juniperus communis. Heathland and flush habitats exist within open areas and on the periphery. The heathy nature of the ground flora is characteristic of oakwoods in eastern Scotland, with frequent heather Calluna vulgaris and bilberry Vaccinium myrtillus. .
Loch Etive Woods Highlands and Islands
Loch Etive Woods in western Scotland is one of three sites representing old sessile oak woods in the most bryophyte-rich zone in the UK, the south-west Highlands zone. The diversity of soils and physical conditions leads to transitions between oakwood and both wet alder Alnus glutinosa and base-rich ash-elm-hazel Fraxinus excelsior-Ulmus-Corylus avellana stands, giving additional patterns of structural variation and transitions. The woods support important populations of the rare chequered skipper butterfly Carterocephalus palaemon.
Loch Lomond Woods Eastern Scotland, South Western Scotland
Loch Lomond Woods is one of three sites representing old sessile oak woods in the most bryophyte-rich zone in the UK, the south-west Highlands zone. This extensive block of woodland in western Scotland comprises a mosaic of woodland types, including ash Fraxinus excelsior, elm Ulmus spp. and alder Alnus glutinosa woodland, which adds to the ecological variation of the site. Pedunculate oak Quercus robur, rather than sessile oak Quercus petraea, is locally abundant, and the oak stands intergrade in places with ash-elm stands, and with alder at flushed sites by the loch. The stands on the islands include areas that have been less subject to grazing than many other examples of this type of woodland.
Loch Maree Complex Highlands and Islands
The Loch Maree area in north-west Scotland is representative of old sessile oak woods of the north-west Highlands bryophyte zone. The ground flora communities range from those favouring base-rich areas through to those dominated by dwarf shrubs in more acidic areas. A distinct feature of parts of this site is the juxtaposition of oakwood and the Annex I type 91C0 Caledonian forest, for which this site is also selected. Oak-dominated woodland on the lower slopes grades through a series of transition communities to Scots pine Pinus sylvestris and birch Betula spp. communities at higher altitudes.
Loch Moidart and Loch Shiel Woods Highlands and Islands
This composite site comprises a series of sizeable woodlands around Loch Moidart and on the northern shores of Loch Shiel. Extensive oak Quercus spp. woodland occurs around Loch Moidart, which in places has a diverse flora due to outcrops of basic rock; there is also a rich Atlantic bryophyte and lichen flora. The woods fringing Loch Shiel are similar, but less disturbed by development. This complex is one of a number of sites representing the Mid-west Highlands Atlantic bryophyte zone.
Morvern Woods Highlands and Islands
Morvern Woods complex comprises five woodland areas located on the Morvern Peninsula in the south-west Highlands. The site contains important stands of old sessile oak woods in both inland and exposed coastal locations. The woods are developed on predominantly acid soils and are dominated by oak with birch Betula spp. Ash Fraxinus excelsior, wych elm Ulmus glabra and hazel Corylus avellana are present where there are more base-rich soils. The steep sea cliffs and deeply incised ravines of Garbh Shlios are difficult to access and are largely undisturbed. The lichen and bryophyte flora of the complex is outstanding, and the vascular plant flora is also extremely rich. Several highly oceanic species, such as hay-scented buckler fern Dryopteris aemula and Tunbridge filmy fern Hymenophyllum tunbrigense, are present.
Mull Oakwoods Highlands and Islands
This complex of woodlands on the island of Mull is the largest remaining example of native woodland in the Hebrides. The Ardura-River Lussa section of the site features open oak-birch Quercus-Betula woodland with ash-hazel Fraxinus excelsior-Corylus avellana on base-rich soils, and alder Alnus glutinosa along stream courses. The stands of open oak woodland at Loch Ba have been less intensively exploited in the past than other deciduous woods on Mull, resulting in older standards and fewer multiple-stemmed trees. Birch woodland characteristically dominates the upper slopes. The site, which lies at the southern limit of the Mid-west Atlantic bryophyte zone, supports a rich assemblage of oceanic lichens, bryophytes, flowering plants and ferns.
Naddle Forest Cumbria
The woodland lies on steep boulder-strewn slopes, with the old sessile oak wood element tending to be more on the upper slopes, with ash Fraxinus excelsior and alder Alnus glutinosa lower down. The ground flora under the oak–birch areas is variable, ranging from acidic bilberry Vaccinium myrtillus-dominated areas to bluebell Hyacinthoides non-scripta on the deeper soils. The bryophyte communities are best-developed on the rocks and damp cliff faces; Atlantic species occur, although not as abundantly as in the Borrowdale valley farther west. The woods occur in association with wet and dry heath and juniper Juniperus communis communities.
North Pembrokeshire Woodlands/ Coedydd Gogledd Sir Benfro West Wales and The Valleys
North Pembrokeshire Woodlands is an example of old sessile oak wood in the south-west of the habitat’s range in Wales, and at the extreme west of its UK range at this latitude. The site is a complex of diverse woodland units, which range from strongly acidic upland oakwood to areas transitional to lowland oakwood; important fragments of floodplain woodland occur in the valley bottoms. A variety of management treatments are in place, with minimum intervention, managed high forest, active coppice, and well-established wood-pasture all represented. The woods have an exceptional diversity of rare epiphytic lichens.
North Pennine Moors Cumbria, North Yorkshire, Northumberland and Tyne and Wear, Tees Valley and Durham
Birk Gill Wood is an example of old sessile oak woods well to the east of the habitat’s main distribution in the UK. However, this sheltered river valley shows the characteristic rich bryophyte and lichen communities of the type under a canopy of oak, birch Betula sp. and rowan Sorbus aucuparia. The slopes are boulder-strewn, with mixtures of heather Calluna vulgaris, bilberry Vaccinium myrtillus and moss carpets in the ground flora.
Onich to North Ballachulish Woods Highlands and Islands
Onich to North Ballachulish Woods extends from sea level to over 400 metres above sea level and incorporates woodland on north-, south- and west-facing slopes on a variety of different rock types. The site’s varying physical features have resulted in the development of a diverse mixture of vegetation types. Old sessile oak woods are best-developed on the lower parts of the south-facing slopes. The woods are very variable in species composition, with four oak–birchQuercus–Betula NVC woodland types represented. The woods comprise a mix of downy birch Betula pubescens, rowan Sorbus aucuparia, sessile oak Quercus petraea, hazel Corylus avellana, holly Ilex aquifolium and ash Fraxinus excelsior in differing proportions. The ground flora is equally variable, ranging from predominantly grassy, with sweet vernal-grass Anthoxanthum odoratum and wavy hair-grass Deschampsia flexuosa particularly abundant, to heathy, dominated by heather Calluna vulgaris and bilberry Vaccinium myrtillus, or mossy, with species such as Dicranum majus, Rhytidiadelphus loreus and Hylocomium splendens forming deep mats. The woods also support a well-developed epiphytic Lobarion lichen flora and a rich assemblage of bryophytes, including a particularly good representation of both oceanic and calcicolous species. Some of the bryophytes, such as Bazzania trilobata, Plagiochila killarniensis and Ptilium crista-castrensis are nationally uncommon. Natural regeneration and expansion of the habitat is occurring around the wood’s current margins. There are transitions to the Annex I habitat H9180 Tilio-acerion forests on slopes, screes and ravines, and also from woodland to heath and mire habitats. The mammalian fauna includes pine marten Martes martes, red squirrel Sciurus vulgaris and badger Meles meles.
Owenkillew River Northern Ireland
The Owenkillew River is associated with several woodlands which in combination represent one of the best examples of old sessile oak wood in Northern Ireland. The woods contain a number of associated physical features, including waterfalls, gorges, cliffs and scattered boulder scree, which contribute to the diversity of the woodland communities. The woodland canopy is variable, but is generally dominated by sessile oak Quercus petraea with frequent downy birch Betula pubescens. The shrub layer consists of rowan Sorbus aucuparia and holly Ilex aquifolium, with hazel Corylus avellana locally frequent and occasional goat willow Salix caprea. In places, the ground flora is dominated by grasses, including wavy hair-grass Deschampsia flexuosa, and calcifuge mosses such as Rhytidiadelphus loreus. Where grazing is absent, bilberry Vaccinium myrtillus, great wood-rush Luzula sylvatica and bluebell Hyacinthoides non-scripta are dominant in the ground flora.
Rhinog West Wales and The Valleys
Rhinog in north Wales contains high-quality examples of old sessile oak woods. This woodland is continuous with that in the adjacent Coedydd Derw a Safleoedd Ystlumod Meirion/ Meirionnydd Oakwoods and Bat Sites, and is best considered with that site.
Rostrevor Wood Northern Ireland
Rostrevor Wood occurs on the lower slopes of the Mourne Mountains in the south-east of Northern Ireland. As a result, it has a drier climate than most of the other examples of old sessile oak woods in Northern Ireland. The wood has a diverse structure with a tall and mature canopy dominated by oak Quercus spp., and a well-developed understorey of hazel Corylus avellana with occasional holly Ilex aquifolium and rowan Sorbus aucuparia. Bramble Rubus fruticosus agg., with bilberry Vaccinium myrtillus, honeysuckle Lonicera periclymenum and ferns make up the field layer, and the dense ground flora is dominated by extensive carpets of great wood-rush Luzula sylvatica with scattered wood-sorrel Oxalis acetosella. The wood supports a number of plant species that are scarce in Northern Ireland, such as toothwort Lathraea squamaria, bird’s-nest orchid Neottia nidus-avis and wood fescue Festuca altissima.
South Dartmoor Woods Devon
This complex is the most southerly of the sites selected and is representative of old sessile oak woods in south-west England, with regionally important assemblages of lower plants and dry Lobarion communities that are unique in Western Europe. The woods are notable for the variations in stand type that reflect past management (old coppice and high forest) and also include grazed and ungrazed areas. The woodland is part of a complex mosaic that includes heathland and species associated with open ground, such as the high brown fritillary Argynnis adippe and pearl-bordered fritillary butterfly Boloria euphrosyne. Variations also arise due to geology, resulting in the presence of small-leaved lime Tilia cordata, ash Fraxinus excelsior, wild service tree Sorbus torminalis, and small areas of wet woodland dominated by alder Alnus glutinosa and willow Salix spp.
South Pennine Moors Cheshire, Derbyshire and Nottinghamshire, Greater Manchester, Lancashire, North Yorkshire, Shropshire and Staffordshire, South Yorkshire, West Yorkshire
Around the fringes of the upland heath and bog of the south Pennines are blocks of old sessile oak woods, usually on slopes. These tend to be dryer than those further north and west, such that the bryophyte communities are less developed (although this lowered diversity may in some instances have been exaggerated by the effects of 19th century air pollution). Other components of the ground flora such as grasses, dwarf shrubs and ferns are common. Small areas of alder woodland along stream-sides add to the overall richness of the woods.
Sugar Loaf Woodlands West Wales and The Valleys
Sugar Loaf Woodlands are the largest example of old sessile oak woods near the south-eastern fringe of the habitat’s range in the UK and Europe. The relatively dry situation restricts the development of the Atlantic flora associated with the habitat, but the main floristic components of sessile oak Quercus petraea canopy, acidic ground flora (typically of bilberry Vaccinium myrtillus and wavy hair-grass Deschampsia flexuosa) and extensive fern and bryophyte cover are in place. The woodland is grazed, but regenerates within gaps and at the fringes, where transitions to upland grassland and heath communities occur.
Sunart Extra-Regio, Highlands and Islands
Sunart on the west coast of Scotland contains the richest complex of Atlantic bryophyte-rich old sessile oak woods in the UK and is representative of the mid-west Highlands bryophyte zone. The site is also characterised by one of the UK’s most extensive areas of ancient semi-natural woodland, much of which is oak-dominated. However, the woodland canopy is varied, with areas of birch Betula spp., ash Fraxinus excelsior and hazel Corylus avellana, and alder Alnus glutinosa on wet ground. Typically, oak-dominated woodland on lower slopes gives way to birch woodland at higher altitudes, and uninterrupted transitions to marine habitats are found along the shore, a rare situation in British woodlands. The woods support a rich fern flora and an impressive range of lichens, including well-developed lungwort Lobarion spp. communities and many rarities. The rare chequered skipper butterfly Carterocephalus palaemon has a strong population within these woods.
Tarbert Woods Highlands and Islands
Tarbert Woods comprises a large coastal strip of fragmented broad-leaved woodland with good stands of old sessile oak woods, which are very important for their oceanic bryophyte communities. The numerous streams which traverse the site have in places cut deep ravines, and together with the sheltered north-east aspect these provide very humid conditions which support thriving populations of ferns and bryophytes. Amongst the 180 bryophyte species recorded are 47 Atlantic species, including Sematophyllum micans and Plagiochila atlantica. The woodland rises in altitude from sea level up to 150 m within around 450 m of the coast, and as a consequence shows marked community zonation. The lower slopes are dominated by oak-birch Quercus-Betula woodland, and downy birch Betula pubescens is the dominant tree throughout the woods with little sign of past management specifically as oak woodland, except around old settlements. Ash Fraxinus excelsior woodland is associated with many of the streams and ravines where more base-rich conditions prevail, whilst areas of alder and willow occur near the coast.
Taynish and Knapdale Woods Highlands and Islands
This continuous block of woodland on the west coast of Scotland is representative of old sessile oak woods in the rich south-west Highlands bryophyte zone. The site is notable for its outstanding lichen and bryophyte communities, which include species with a predominantly southern distribution, such as the rare Physcia clementei. In the less acidic areas a rich ground flora occurs, including narrow-leaved helleborine Cephalanthera longifolia. There are also transitions to open bog-filled hollows with the Annex II species 1065 Marsh fritillary Euphydryas aurinia and several small mesotrophic lochs.
Tintagel-Marsland-Clovelly Coast Cornwall and Isles of Scilly
Stretches of old sessile oak wood occur at various points along this section of coast. The trees are frequently wind-pruned, sometimes to the point where they are barely taller than the heather Calluna vulgaris. The oak communities include small patches of richer ash Fraxinus excelsior and alder Alnus glutinosa woodland. The bryophyte and lichen assemblages are particularly rich, and the Atlantic influence is also shown in the abundance of hay-scented buckler-fern Dryopteris aemula.
Trossachs Woods Eastern Scotland
This complex of ancient, semi-natural woodland sites is one of the largest and most diverse in central Scotland, and represents old sessile oak woods within the South-west Highlands Atlantic bryophyte zone. The woodland is largely dominated by sessile oak Quercus petraea with downy birch Betula pubescens on acid soils. Within localised pockets, nutrient enrichment occurs, giving rise to ash Fraxinus excelsior, and where groundwater flushing occurs alder Alnus glutinosa dominates with ash and hazel Corylus avellana. The islands within Loch Katrine support ungrazed tree and shrub communities including juniper Juniperus communis. The ground flora of both sites in the complex is rich and the complex is notable for the presence of Bazzania trilobata, a liverwort typical of more western oceanic oakwoods.
Ullswater Oakwoods Cumbria
Around Ullswater there is a cluster of old sessile oak woods, sometimes in association with other woodland types of ash Fraxinus excelsior and alder Alnus glutinosa. The woods show outstanding bryophyte assemblages (including northern species such as Ptilium crista-castrensis) and also include areas rich in saproxylic invertebrates.
Upper Lough Erne Northern Ireland
Upper Lough Erne represents one of the largest areas of semi-natural woodland remaining in Northern Ireland. Drier soils support mature stands of old sessile oak woods, which are particularly well-developed to the south of the lough. The woodlands consist of a canopy dominated by oak Quercus petraea, with occasional ash Fraxinus excelsior and birch Betula pubescens. Hazel Corylus avellana and holly Ilex aquifolium often form a distinct shrub layer. The ground flora is very variable and consists of a wide variety of species, including bluebell Hyacinthoides non-scripta, sanicle Sanicula europaea, goldilocks buttercup Ranunculus auricomus, great wood-rush Luzula sylvatica, and an abundance of the scarce thin-spiked wood-sedge Carex strigosa.
Upper Strathearn Oakwoods Eastern Scotland
This complex of sites in Central Scotland contains examples of old sessile oak woods towards the eastern end of the habitat’s range within Scotland. It is one of two sites within the series representing the Eastern Highlands Atlantic Bryophyte zone. The complex includes one of the most extensive deciduous woodlands in Tayside, which was formerly managed for coppice wood production and is now comprised largely of non-singled stems which give a good structural diversity. Several sub-oceanic epiphytic bryophytes occur, and one of the woods is of national importance for its lichen flora with an outstandingly high number of epiphytic species including many characteristic of old woodland.

SACs/SCIs/cSACs where this Annex I habitat is a qualifying feature, but not a primary reason for site selection

Arnecliff and Park Hole Woods North Yorkshire
Ben Nevis Highlands and Islands
Cadair Idris West Wales and The Valleys
Deeside and Buckley Newt Sites East Wales
Derryleckagh Northern Ireland
Eryri/ Snowdonia West Wales and The Valleys
Exmoor Heaths Devon, Dorset and Somerset
Hollymount Northern Ireland
Inverpolly Highlands and Islands
Lough Melvin Northern Ireland
Migneint-Arenig-Dduallt West Wales and The Valleys
Moine Mhor Highlands and Islands
Monawilkin Northern Ireland
Morecambe Bay Pavements Cumbria, Lancashire
Ness Woods Highlands and Islands
Peatlands Park Northern Ireland
River Camel Cornwall and Isles of Scilly
River Faughan and Tributaries Northern Ireland
River Roe and Tributaries Northern Ireland
The Stiperstones and The Hollies Shropshire and Staffordshire
Yewbarrow Woods Cumbria
 

Many designated sites are on private land: the listing of a site in these pages does not imply any right of public access.