Peat is a
soil that is made up of the partially decomposed remains of dead plants
which have accumulated on top of eachother in waterlogged places for thousands
of years. Areas where peat accumulates are called peatlands. Peat is brownish-black
in colour and in it’s natural state is composed of 90% water and
10% solid material. It consists of Sphagnum moss along with the roots,
leaves, flowers and seeds of heathers, grasses and sedges. Occasionally
the trunks and roots of trees such as scots pine, oak, birch and yew are
also present in the peat.
As the summer draws to a close, the boglands stand out most distinctively
from the rest of the landscape. The leaves of both the common bog cotton
and, in particular, the deer grass (Scirpus caesitosus) turn the sward
to a brilliant russet which seems to glow in the low winter light. These
russet patches, swathes, or even entire landscapes, are sure indicators
of bogland.
Raised bogs occur in the midlands of Ireland and in the Bann River Valley
where rainfall is between 800 and 900mm per year. Blanket bogs are found
along the west coast of Ireland and in mountainous areas around the country
where rainfall is 1200mm per year or more. 17% of the land surface of
this country is covered with peatland and Bord na Mona who are responsible
for industrial peatland development in Ireland, owns 25% of the midland
raised bogs.
Raised
bog formation started at the end if the last glaciation – some
10,000 years ago – when the glaciers had retreated northward.
At this time much of central Ireland was covered by shallow lakes left
behind by the melting ice. Lakes also formed where glacial ridges, such
as eskers, impeded free drainage and trapped the water. At the base
of these shallow lakes there were deposits of lake marl overlying clay
and glacial drift. These lakes were fed by mineral rich groundwater
and springs and supported floating plant communities, which sometimes
produced a thin peat layer just above the lake marl. The lake edges
were dominated by tall reed and sedge beds. As these plants died, their
remains fell into the water and were only partly decomposed. They collected
as peat on the lake bed. With time this process formed a thick layer
of reed pear that rose towards the waters surface. As the peat surface
approached the upper water level, sedges invaded and their remains added
to the accumulating fen peat.
Contrary
to popular belief, boglands are not dreary places: a close examination
reveals a wealth of colour and mixture of distinctive scents. The
Sphagnum bog mosses themselves have a vivid colour, some are deep
wine-red, others are brilliant orange, gingery brown, while yet
others have bright greens mixed with delicate salmon-pinks. They
combine to forma a scene as intricate and colourful as a Persian
rug. Dotted through thissoft carpet you can find the greens and
pinks of heaths and heathers (Erica and Calluna) bright splashes
of yellow and orange from the bog asphodel (Narthecium ossifragum),
fuchsia-pinks and ruby reds of cranberry flowers and berries (Vaccimium
oxycoccus) and the delicate white and pink frothy flowers of the
bog bean (Merryanthes trifoliate).
In
time the fen peat layer in these shallow lakes became so thick (up to 2m)
that the roots of plants growing on the surface were no longer in contact
with the calcium rich groundwater. When this happened the only source of
minerals for the plants came from rainwater, a very poor source of the essential
minerals needed for plant growth. As a result plants invaded that were able
to grow in the mineral poor habitats on the surface of the peatland. The
best indicator of the changing conditions was the invasion of the bog moss
or Sphagnum. The moss became common in such transitional fen/bog habitats,
and made the ground even more acid, , by its ion exchange activity. Plants
typical of raised bogs, such as Heathers, Sundews and Deer Sedge invaded
the tops of the sphagnum hummocks, completing the invasion of bog species.
The
Bog Moss is important as it acts like a sponge or candle wick, drawing
up water and keeping the surface of the bog wet and waterlogged, in all
but the driest periods. So, even though the bog continued to grow upwards,
away from the water table, the Bog Moss ensured that the water table rose
in tandem with the rising peat level. During the long history of bog growth,
there has been occasional changes in the overall climate in Ireland. About
4,500 years ago the annual rainfall decreased. This caused bog surfaces
to dry, and allowed the invasion and establishment of a pine wood land
on the surface of the bog. This woodland persisted for some 500 years,
until the climate changed again and became wetter. Rapid bog growth recommenced
as the surface became waterlogged, and trees died. Tree stumps and whole
tree trunks were buried and preserved in the rapidly accumulating sphagnum
peat. The layers of fen and sphagnum peat and the buried pine stumps are
often seen exposed by turf cutters at the margins of raised bogs.
Perhaps the most spectacular and best-known adaptation to life on the
bogs is the carnivorous plant. Several species have developed the ability
to trap and eat animals as a means of supplementing their meagre diet.
The animals are very small and almost exclusively insects, although the
sundews (Drosera species ) are able to trap the bigger darter dragonflies
which have wing spans as wide as the human hand.
The sweet scented bog myrtle (myrica gale), typical of western boglands,
forms a partnership with bacteria in its roots to obtain extra nitrogen,
while the common bog cotton (eriophorum agustiffolium ) uses a snorkel
technique, relying on large air filled cells in its roots based to survive
in oxygen poor environment beneath the living carpet of sphagnum. A family
of tiny brilliantly coloured `jewel’ beetles (Donaica species) use
these air spaces as living quarters.
Boglands are home to only a few species of animal, yet can boast the largest
animal in Ireland today-the red deer. Red deer can be found wallowing
in peat baths to rid themselves of flies and parasites, Otters and badgers
occasionally venture out into the bogs in search of the eggs and chicks
of ground nesting plains.
The songs of skylarks and meadow pipits provides incessant background
noise on the boglands. But perhaps the most characteristics sounds of
the boglands are, first, the rustle and buzz of dragonfly wings on a still,
sunny day as these huge insects patrol the pools and hollows that are
dotted across the bogs, and cries of the birds. Most evocative of all,
however, is the combination of bird-songs:the cry of the curlew, the shout
of the grouse and the sad “wheep” of the golden plover.
Peat has played an important role in the history of Ireland and the development
of Ireland and in particular the midland counties. There is documentary
evidence that peat has been used as a fuel since the 8th century in this
country. The destruction of our woodlands in the 17th century meant the
only other fuel available was peat. Prior to the famine the population
of this country was 8.2 million people. It is estimated that at this stage
6/7 million tonnes of peat were used in this country annually. Records
show that the earliest attempts at peat use on a large scale was reclamation
of the peatlands for agricultural purposes. Several other uses for peat
were found in the 19th century varying from peat paper (1835), to peat
charcoal (1850), peat moss products (1850), turf distillation (1849) etc.
None of these enterprises were successful at that time but showed the
commitment the Irish people had in trying to make good use from this freely
available natural resource
Moving forward then, to World War 2, Ireland found itself in economic
isolation, in particular in relation to its energy supply. That led to
the establishment of Bord na Mona and the ESB, in the mid 1940’s,
with the role of developing the resources and creating finance in the
midlands. This is the context in which the peatlands were developed for
industrial purposes . Such this time Bord na Mona developed the raised
bogs to derive fuel to generate electricity, create other fuel and conversation
issues relating to this development but the after use of these bogs known
as cutaways are of equal importance also. The creation of wet lands and
parklands from these cutaway bogs are a positive development, in particular
the Bord na Mona parklands is a very good example of this.
The parklands projects is both interesting and exciting, its significance
far exceeding the 2,000 hectare site itself. During the 1940’s and
50’s Bord na Mona – Irish peat board, was set up to 2develop
Ireland’s peat resources”, Since its establishment it has
purchased thousands of hectares of peatland and now owns approximately
7% or 80,000 hectares of Irelands lowlands bogs. Once considered an economic
wasteland these bogs have been turned into a commercial enterprise; peat
is milled for energy production, harvested for horticultural products
and commercial fuel production. Over recent years large tracts of bog
have been cutaway- “cutaway” being the term used to describe
and area that has come out of production once all commercial peat has
been removed. The Boora bog complex in Co. Offaly is one of the oldest
areas of commercial production and as a result was the first area where
large tracts of cutaway emerged. But what was to be done with these vast
expanses of land? Over a short period of time it has been flooded and
allowed to recolonise naturally. As a result of this development the area
has become a new homre to many birds and animals at risk in local farm
areas.
Hundreds of birds and animals have made a new home in the magnificent
wilderness. Surprisingly it has only taken a short length of time for
plants and animals to recolonise the area. Different varities of plants
and bird communities have developed. Over 250 vascular plants have grown
and its developed into one of the most amazing mosaic patterns of life
and habitat range in Ireland. The habitat range goes from woodlands to
open grasslands, to reed beds, to heather areas, to mossy areas, and rush
covered lands. The cutaway bog landscape is a life line for many bird
species today. Natural recolonisation of large tracts of cutaway is providing
new habitats, replacing those that have disappeared from farmland. The
absence of fertilisers and pesticides have allowed a rich diversity of
insects and plants, and birds flourish, creating a mosaic of wetland and
terrestrial habitats throughout. Resident and migratory birds alike are
attracted to the cutaways in increasing numbers.
Lough Boora Mesolithic
site was discovered in 1977 when what was first thought to be a stone
track way was brought to the attention of the National Museum. This was
investigated and found to be the storm shoreline of a post-glacial lake,
a remnant of an era when the Shannon and its lakes - Lough Ree and Lough
Derg covered much more of the Midlands than today. Further investigation
of the shoreline revealed the charcoal remains of ancient camp fires.
Associated with these were approximately 1,500 artefacts, many of them
carefully worked black stone tools made of chert - a stone like flint,
found locally in glacial deposits. The campfire sites, dated to between
6800 and 6500 BC, were the temporary campsites of hunters during the Mesolithic
age (Middle Stone Age). The site itself is not the most spectacular archaeological
feature as nothing remains of these encampments. However, it is one of
the most important archaeological finds in Ireland. Prior to its discovery
it was thought that the first human settlements were near to the coast
and that the midlands remained uncolonised. The discovery of the Lough
Boora Mesolithic site has proven this to be inaccurate and pushed the
accepted date for the colonisation of the midlands back by over 3,000
years! The site, part of which is now a National Heritage Area, is situated
at the end of a 1.75 km walk, which is being developed as a sculpture
trail. Beginning at the edge of Boora Lake and continuing through coniferous,
oak and birch woodland, the walk ends at the storm shoreline in a remote
open area. A stone plaque marks the location of the settlement.
Mongan Bog is a midland raised bog of medium size situated immediately
east of the monastic site of Clonmacnoise, Co. Offaly, and 12 km south
of Athlone. It is situated in a basin, surrounded on 95% of its perimeter
by high ground on mineral soil. At two points in the north it shares a
common boundary with the Pilgrim's Road Esker. Most of the bog is a Statutory
Nature Reserve, established in 1987. The bog has been the subject of on-going
intensive research since 1972. Mongan Bog is a mostly intact and unusually
wet raised bog with classic hummock and pool formations over a large proportion
of the surface, largely due to its unusual surrounding topography. It
has several features of special zoological interest. In addition its lowest
strata are among the oldest in Ireland. Scenically it is part of an area
rich in intact natural features (callows, eskers, limestone pavement)
which enhances its importance even more. Raised bogs, which are, actively
growing are a rare habitat in Europe and are listed on Annex I of the
EU Habitats Directive as a priority habitat. The ongoing intensive research
on all aspects of bog ecology reinforces its international importance.
Clara Bog is situated some 2 km south of Clara village. Much of it is
state-owned and designated a statutory nature reserve. Clara Bog has long
been regarded as one of the most important lowland raised bogs in the
country, being the largest remaining example of the true Midland sub-type.
It has well-developed hummock and hollow complexes and one of the few
remaining soak systems. The bog vegetation has been much studied and is
well known. Variations in the proportions of Bog moss (Sphagnum spp.),
Heather (Calluna vulgaris) and Cotton grass (Eriophorum spp.) has been
related to ecological features such as pools, soaks and ridges. Active
raised bogs, once characteristic of central Ireland, are now rare and
vulnerable, and have been recognised by the European Union as a habitat
of international importance. Ireland has a special responsibility to conserve
the best of its remaining bogs. Further drainage, peat extraction, burning
or attempted land reclamation is not consistent with this responsibility.