Milling the Peat Bog In its undrained state the bog is 95% water and is not solid enough to support the weight of machinery. A criss-cross network of drains is opened up across the entire bog, using a disc ditcher. Draining the bog takes between 5 and 7 years to reduce the moisture content to 90%. At this stage all of the surface vegetation is removed, the bog is leveled and a network of light railways are laid across the bog. The bog is ready for peat production and has a distinctive appearance. It consists of a series of peat fields, 15m wide, with intervening drains. This improves runoff and drainage. Eleven of these parallel fields forms a production unit, five working fields on each side of one containing a central stockpile. The peat harvesting cycle begins with milling, or breaking up of the surface of the bog to a depth of 10 to 15mm. A spoon harrow, towed by a tractor, turns the milled peat over to speed up the drying process. The dried peat crumb contains approximately 45% moisture. Next, it is gathered into ridges using a ridging machine. Then a mechanical harvester lifts each ridge and carries the peat on a belt conveyor over to the ridge in the adjoining field, repeating the process until the ridges from all five working fields on each side have been delivered into the central stockpile. The milled peat is stored in stockpile until required. It is removed from the bog by train. The average milled peat harvesting cycle is about three days and there are about 12 harvests each year from April to September. At present Bord na Móna produces approximately 3.5 million tonnes of milled peat each year. Three million tonnes are supplied to five peat-fired power stations run by the Electricity Supply Board in Ferbane, Rhode and Shannonbridge in Co. Offaly, Lanesboro Co. Longford and Bellacorrick, Co. Mayo. These have a combined capacity of 350 megawatts, which meets 11% of Ireland's electricity requirements. The remaining peat is manufactured into peat briquettes and moss peat gardening products. Peat Briquettes are produced in three factories, Croghan and Derrinlough in Co. Offaly and Littleton in Co. Tipperary Peat for horticultural use is derived from the Sphagnum moss content of the bog and is processed at three horticultural plants. Bord na Móna can be contacted at: Main Street, Newbridge, Co. Kildare, Tel: 045-439000. Web site: www.bnm.ie

Registered Charity Number CHY6829

All photographs courtesy of Bord na Móna