In the following account of this LCA it should be noted that for consistency, the biodiversity section follows the standard order for all LCAs even though some of the communities discussed later may have more importance for biodiversity than those discussed earlier
Key CharacteristicsBroadleaved woodlands occupy less than 2% of the LCA, mainly coniferous State Forests almost 20% and are dominated by Sitka spruce. Most of the forests have been planted on peaty soils or peat, in some instances on intact blanket bog. These forests have generally detracted from the biodiversity of the LCA, but red squirrel is recorded for most forests; in open areas within the forests marsh fritillary and Irish hare have also been recorded.
Many of the broadleaved woodlands in the LCA occur alongside streams on the scarp edge of the plateau or on the steep slopes themselves. They are often tall shrubs and scrub and dominated by hazel, which may be accompanied by alder and willow in damper sites or by ash and birch on drier slopes. In some instances, these woods have extended out from former shelterbelts and in others occasional beech, sycamore and conifers have been planted. Most are imperfectly fenced, open to grazing and show evidence of recent and past piecemeal coppicing.
The woodland at The Umbra may be divided into two parts - one on the north-facing scarp slope, the other between the foot of the scarp and the sand dunes. The former is an extensive example of an upland mixed ashwood; ash is dominant, but there is a wide mix of species including sycamore, hazel, birch, alder, willow and occasional conifers. This is a very varied woodland ranging from areas of scrub through mixed deciduous woodland to almost pure stands of hazel or ash or sycamore and some wet woodland. The understorey is well-developed and the diverse herb layer reflects the base-rich soils, some of which are also waterlogged. Although there is field evidence of past and present use of the trees, of thinning and felling and of grazing, there is also regeneration of the trees.
The dune-side woodlands at The Umbra although with abundant sycamore and ash, also have wet woodland with alder and willows. The woods here are part of a mix of habitats that include examples of the progression of dune development and maturity and the associated vegetation. The otter and the small eggar moth are recorded at The Umbra.
Although most of the broadleaved woodlands show signs of regeneration with saplings of the canopy species, they also show piecemeal coppicing, shredding, felling and clearing and grazing. Several of the woods are known to have been present in the 1830s and the herb species may also be indicative of ancient woodland.
Grassland and ArableThere is hardly any arable land and less than 10% of the LCA is in improved pasture. These figures reflect the upland nature of the LCA; small patches of improved pasture are found only where lowland has been included around the edge. In contrast, rough grassland is frequent, generally on the steep slopes that bound the plateau. Many of these grasslands are on peaty or humic soils and are acidic with purple moor grass, fescues and common bent - the species depending on the soils and past management history. At Binevenagh ASSI (also cSAC, NNR) the grassland below the cliff is typically dominated by fescues and common bent with herbs such as heath bedstraw and tormentil. These grasslands are nationally important for fungi, particularly waxcaps. However, there are also more basic grasslands; dry, calcareous grassland occurs with fine-leaved grasses, sedges and herbs dominating the sward. Wild thyme, eyebright and harebell are all frequent, with species such as field gentian and thyme broomrape more notable.
Cliff CommunitiesInland cliffs are rare in Northern Ireland, but they are quite frequent in the LCA on the sharp western and northern edge of this northern extension of the Sperrin Mountains. Some of these cliffs have rare communities, for example the cliffs at Binevenagh have a unique assemblage of arctic-alpine plants and bryophytes, including mountain avens, purple saxifrage and brown screw moss - a vulnerable moss typical of slightly base-rich conditions on friable basalt.
Heaths and BogsAs noted above, much of the blanket peatland in this LCA has been planted with coniferous forest. Additionally, cut-over peat is extensive and, given the altitude and steep slopes there is a considerable amount of eroded peat. Nevertheless, there are remaining areas of intact peat; amongst the largest is at Altikeeragh ASSI where there is an extensive upland raised dome with a well-developed pool and hummock complex. Similarly, much of the blanket bog at Carn/Glenshane Pass ASSI (and cSAC) remains intact and exhibits a number of notable structural features, including a large, well-developed hummock and pool system and extensive eroding hagg complexes. Dwarf shrubs of heather and sedges dominate the blanket bog vegetation over a carpet of bog mosses. The site includes rare and unusual plant species.
On slopes that are too steep for deep peat to form, a mosaic of wet heath, dry heath, purple moor grass and flushed grasslands may be found. Together with the various forms of blanket bog (cut, eroded, intact), these habitats add diversity to this large, upland area. Breeding red grouse are recorded.
Mechanized peat cutting for fuel is not widespread in the LCA, but there is an extensive area at Altikeeragh; this is largely on formerly cut-over peat but poses a threat to the adjacent intact bog. Overgrazing is a feature of some areas of heath; for example, the heath on the scarp slopes at Benbradagh has been almost eradicated by prolonged overgrazing. There is also evidence of fires extending onto some of the intact bog surfaces.
The blanket bog of this LCA clearly has been under threat from a number of sources. The threat from State Forestry has diminished since there is now a presumption against planting new forests on ombrogenous peat. Blanket bog is rare in Europe and Ireland, including Northern Ireland, has a significant proportion of the remaining blanket bog; this LCA is fortunate in still retaining areas of intact bog with structural features and rare plants and animals.
Wetlands and LakesThere are no extensive wetlands in the LCA. A small patch of fen and reeds occurs at Binevenagh Lake and fen meadow at Ballyrisk More. Some of the rivers and headwaters are salmonid streams, but few are threatened by either chemical or particulate pollution. However, future forestry operations, such as felling, may pose a potential threat.
Key IssuesGeneral actions for UK and NI Priority Habitats and Priority Species are detailed in the Habitat Action Plans and Species Action Plans.
WOODLANDSIssue: woodland cover of variable biodiversity value but including significant examples of NI Priority Habitats upland mixed ashwood and wet woodland.
Actions:
Issue: poor biodiversity of improved pastures as a result of relatively intense management, however nationally important grasslands occur at Binevenagh ASSI
Actions:
Issue: rare cliff vegetation, species-rich grassland, bryophyte-rich scree, rare plants, bryophytes and fungi
Actions:
Issue: intact blanket bogs, which are of national and international importance, are threatened and include rare and unusual plant species.
Actions:
Issue: loss of heathland and decline in its biodiversity
Action:
Issue: small areas of wetland and salmonid streams may be at risk from future forestry operations
Actions: