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Bog Wood

Buried trees and forests are common and widespread in Irish bogs. In extensive areas of the west of Ireland entire forests of pine lie preserved underneath the blanket bog. In raised bogs pine forest is part of the natural vegetation succession from lake to bog. The three important types of wood found preserved in bogs today are Scot's pine, oak and yew. They can be from 4,000 to 7,000 years old.

Pine, often referred to as deal or fir, is found deep in the bog, and occurred in times when the drying of surface peat allowed a migration of pines on to the bogs. These Scot's Pine woodlands were open in character and had an understorey of birch. In the ground layer Ericaceous shrubs or heather species were important including Ling heather and Crowberry. They were maintained on the bog for up to 500 years. Eventually the bog surface became unsuited to tree growth and regeneration of the woodland. As the climate became increasingly wetter and bog growth became active again the trees were drowned and seeds could not germinate. Oak and yew trees are generally found around the edges of the bog and were drowned as the bog expanded out of its basin onto the surrounding mineral soil. The lack of oxygen in waterlogged peat prevents the natural process of decay and ensures the tree trunks and stumps are preserved for years in the accumulating peat.

In the past bog wood had many uses. It was an important resource particularly during the famine. It was often the only timber that people had access to - timber was not available outside the estate woods of the gentry in the 18th and 19th century in Ireland. The preservation of the wood in the bog gave the timber strength and durability. Uses for bog wood included structural timber for houses, rope, fuel, deal torches, thatches and salmon spearing. Occasionally people made a living from the sale of bog wood splits.

The method used to find tree trunks in intact bog remains unexplained today. People would search bogs for areas wherever the early morning dew, frost or snow disappeared first, these areas suggested the presence of buried wood. A long metal probe was used to confirm the presence of timber. It is said that an experienced hand was able to tell the size, the way in which the timber lay, the tree species and the quality of the timber, all with a metal pole. Nowadays bog wood is mainly found through activities such as turf cutting and land drainage. In bogs where peat is being extracted commercially, tree stumps and trunks are dragged out of the peat with a mechanical digger to the edge of the bog. This is essential as the wood remains block peat milling machines.

Production of hand carved bog wood ornaments, jewelry and furniture, was popular in the 17th, 18th and 19th centuries. The jewelry included Tara brooches and Celtic crosses. Much of the carving was coarse and for the tourist trade. Gold, reputedly originating from Wicklow was used to decorate some finely carved pieces.

Most closely associated with the production of bog wood furniture was Arthur Jones. He operated from 1820 - 1860 in Dublin. Jones furniture was elaborately designed aiming to illustrate Irish history. His designs made particular use of the harp, shamrock and the wolfhound. The National Museum in Dublin and Muckross House in Killarney both exhibit examples of bog wood carving and furniture.

Today bog wood has particular importance for artists and scientists. Michael Casey from Longford has made a successful living carving beautiful free form sculptures from bog wood. The wood is dried for up to two years before use. The final sculpture is a result of sanding, rasping, shaping and polishing with bees wax. His work includes one off commissions, awards, collections and smaller pieces. It has received recognition both in Ireland and abroad. He set up the Celtic Roots Studio in association with Bord na Móna. At the studio near Ferbane, Co. Offaly Michael Casey trains students to work the bog oak, yew and pine. Michael's work can be viewed and brought at the studio.

Scientifically, bog wood has proved invaluable as a dating tool and for studying climate change. This is made possible because of annual variation in the diameter size of tree rings. Tree rings are wide in a good and narrow in a poor growth year. Studying variation in the pattern of tree rings is known as dendrochronology. By studying and matching the patterns in tree rings from a wide range of bog wood samples, a year by year chronology can be built up. Queens University in Belfast has a tree ring record compiled from 4,000 bog oak and other ancient oak timbers that spans 7,000 years. A pine chronology for Ireland is also under development. The tree ring chronology allows accurate dating of anything made from oak or pine in Ireland. The annual growth rings in bog wood timbers also give a record of past climatic conditions. The basis of these studies lie in the fact that in a favorable growth year the tree lays down a wide growth ring. In unfavorable years, a narrow ring and so on. The patterns in the rings analysed using statistical packages and related to calendar years give a detailed record of climate change over time.

References

McNally, A. (1990) Dendrochronology of subfossil pine as evidence for environmental change. In Doyle, G.J. (ed.). Ecology and Conservation of Irish Peatlands, pp 15-22. Royal Irish Academy, Dublin.

O'Connell, C. (ed.) (1987) The IPCC Guide to Irish Peatlands. Irish Peatland Conservation Council, Dublin.

Pilcher, J.R. (1990) Ecology of Sub Fossil Oak Woods on Peat. In Doyle, J.D. (ed.). Ecology and Conservation of Irish Peatlands, pp 41-47. Royal Irish Academy, Dublin.

Reddington, C. (1995) Lifting the bog oaks. In The Countryman Winter Vol. 101;1