Blanket bogs are wild areas that cover the lowlands and uplands of the west of Ireland. They are formed of peat soils which are the partially decomposed remains of plants which have built up slowly over thousands of years, in areas where the climate is cool and wet. In the past blanket bogs have been used for peat production, livestock grazing and, more recently, growing conifers, however their value as important wilderness areas is becoming increasingly recognized. Blanket bogs are complex wetland ecosystems which support many plants and animals that are specialised to live in the wet, nutrient-poor, conditions. Irish blanket bogs are among the richest in Europe in terms of their plant and animal life. On the bog, you can find a rich diversity of plant and animal species, including numerous species of moss, lichen, spider and insect as well as larger animal species such as the otter, red grouse and merlin.
Blanket bogs starting developing in Ireland around 7,000 years ago, however
it is thought that they only became widespread around 4,000 years ago when the
climate became much wetter and cooler. Prior to their widespread cutting and
reclamation by people it was estimated that bogs covered 15% of the island of
Ireland. Whilst peat has probably been cut for fuel for thousands of years
it is only in the last century that vast areas have been lost to peat-cutting,
afforestation and agricultural reclamation. Today, it is estimated that only
18% of the original area of blanket bog and 8% of the original area of raised
bog remains of conservation interest.
Two main types of bog occur in Ireland namely blanket bog and raised bog. Although these two bog types have much in common there are important differences in their distribution, development, structure and vegetation. Blanket bogs are confined to the western half of the country and mountainous areas further east where the rainfall exceeds 1200mm per year while raised bogs are largely confined to the midlands where the rainfall amounts are generally below 1200mm per year. Most areas of raised bogs have grown from a lake basin and are typically surrounded by agricultural grassland while blanket bogs tend to be much more extensive and form carpets across flat or gently undulating landscapes. Another noteworthy difference between raised and blanket bogs is peat depth. Raised bogs generally contain deeper peat deposits (typically between 4 and 8 metres) while blanket bogs are generally shallower with a peat depth of between 2 and 5 metres typical. Although raised and blanket bogs support a similar range of plant species, certain species tend to be more frequent in either type. Raised bogs tend to be dominated by deer grass (Trichophorum cespitosum), white-beaked sedge (Rhynchospora alba) and cross-leaved heath (Erica tetralix) while lowland blanket bogs are generally dominated by grasses and sedges, especially purple moor-grass (Molinia caerulea) and black bog rush (Schoenus nigricans). Raised bogs also tend to contain a better-developed Sphagnum layer than blanket bogs.
The sites in this restoration project are blanket bogs, most of which occur
at a low elevation, i.e. less than 150 metres, and thus are termed lowland
blanket bog. The sites in the Slieve Blooms however, occur at a higher
elevation and are referred to as mountain blanket bogs. The main difference
in terms of vegetation cover between these two types of blanket bog is that
lowland blanket bogs tend are dominated by purple moor-grass (Molinia
caerulea) and black bog rush (Schoenus nigricans) while the
drier mountain blanket bogs are generally dominated by ling (Calluna
vulgaris) and hares tail bog cotton (Eriophorum vaginatum).