2000:0830 - CORRHILL BOG, Lisdermot, Offaly

This excavation was carried out in Corhill Bog, Co. Offaly, as part of the 2000 Bord na Móna Archaeological Mitigation Project. This site was traced for a length of approximately 40m during the 1996 IAWU field survey; this season’s work increased its length to over 80m. The 1996 survey recorded several other sites along the same field surface with very similar construction, orientation and composition. At that time these sites were not linked because they meandered along the field surface in a north-west/south-east direction and did not appear to be crossing the shortest stretch of bog. One of these additional sightings was also chosen for excavation within the mitigation strategy document and was subsequently excavated by Ellen OCarroll (see Excavations 2000, No. 829). In effect, the current excavation, along with 00E0333 (Track A) (see Excavations 2000, No. 829) has resolved ten previously recorded structures.

Two cuttings, both measuring 3m x 2m, were excavated. At both cuttings the site was visible on the field surface as an irregular scatter of dried-out brushwood rods. There was very little peat cover remaining over the site, and the majority of this was very dried out. It had a high sphagnum content with some inclusions of ericaceous root and patches of fibrous sedge material. Very little peat was removed from either cutting as some of the brushwood was already exposed on the field surface.

The first cutting excavated revealed a broken, longitudinal brushwood with four fragmentary transverses. There were also four small pegs associated with the transverse elements. The site appears to have been c. 1.3m wide. The brushwood rods varied from 10mm to 40mm in diameter and from 0.15m to 1.3m in length. A light brown peat bordered the southern edge of the site. This peat was poorly humified and contained a large amount of undecomposed sedge material, some eriophorum and patches of sphagnum. The site was placed directly over a darker, more decomposed peat with a higher eriophorum content and less sedge material and sphagnum than the adjoining peat.

There was a higher density of wood present in the second cutting, and the site was 1.25m wide at this location. There were several longitudinal elements supporting some fragmentary transverse elements with occasional pegs. The elements ranged in diameter from 0.02m to 0.47m, and all were broken.

This togher was almost completely destroyed by machine damage and subsequent exposure to the elements. It appears to have been originally composed of transverse brushwood rods supported by longitudinal brushwoods and roundwoods. It varied in width from 1m to 1.3m and ran in a north-west/south-east direction. It did not travel in a straight line but meandered along the field surface. This may be due to the local ground conditions at the time of its construction. The peat with the higher sphagnum content (therefore wetter) along the edge of the site indicates that the site was constructed along the driest rather than the straightest stretch of bog. Environmental samples were taken from both cuttings, and it is hoped to evaluate this theory at a later date. The orientation of the site is interesting in that it appears to provide access into the bog rather than serving as a crossing-point. It is proposed to date a sample from Cutting 2, which will then be compared to 00E0333 (Track A) excavated by Ellen OCarroll, to confirm the true length of the site (see Excavations 2000, No. 829).

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