1997:App3 - IRISH ARCHAEOLOGICAL WETLAND UNIT FIELDWORK 1997—COUNTIES OFFALY, WESTMEATH AND MAYO, Offaly

During the summer of 1997 the IAWU continued its surveys of Bord na Móna-owned bogs in the midlands. Surveys of Tumbeagh Bog, Lemanaghan Works, Co. Offaly, and Bellair Works in counties Offaly and Westmeath were completed, and a survey of Boora Works, Co. Offaly, was started. All of the area covered is owned by Bord na Móna (BnM). Licensed excavations were carried out on a pitfall trap containing red deer remains at Coolcarta East, Co. Galway, and a post row in blanket peat at Drumcullaun, Co. Clare (Excavations 1997, Nos 20 and 196 respectively). An investigation was carried out on a corduroy road at Sharragh, Co. Tipperary (No. 558, Excavations 1997), as well as an assessment of a disturbed crannóg at Frenchgrove, Co. Mayo (see below).

In each bog surveyed a standard IAWU survey strategy was used. BnM bogs have parallel drains set approx. 15m apart and every second drain is walked giving a survey interval of approx. 30m. On the first walk sites are identified and their locations marked. These are then revisited to carry out recording, sampling and the instrument survey. The process is completed rapidly as the bogs are in production, which can reduce the surface area by up to 0.2m per year.

The completed surveys have now identified over 715 sites in Lemanaghan Works, and 17 sites in Bellair Works, and to date the Boora survey has produced 31 sites. This brings the total number of sites known from bogs in north-west County Offaly to over 910, including a small number known prior to the IAWU surveys.

Tumbeagh Bog, Lemanaghan Works
Lemanaghan Works is situated, for the most part, north of the Clara–Ferbane road in north-west County Offaly (see Offaly 6" sheets 7 and 15). It covers approximately 1300ha, which forms part of a larger raised bog complex in the area. The survey of Lemanaghan Works began in 1993 and was completed in 1997 with the survey of Tumbeagh Bog. This bog produced 96 new archaeological sites.

The majority of sites occur in two bands with a number of outliers. The first is located at the northern end of the bog close to the road dividing Tumbeagh from Kilnagarnagh Bog. Here there are a large number of sightings distributed across the bog in a north-east/south-west direction. Most of these contain planks and there are a small number of distinct sites which can be traced for some distance across the bog. A number of dendrochronological dates have been obtained, all of which fall between 1050 BC and 900 BC.

The second band of sites runs north–south along the south-western side of the bog. The density of sites along this band is low although the density increases towards the south. The sites in this area are also more substantial and some can be traced across a number of drains. Trackways and deposits of worked wood were identified, and a perforated wooden shaft was recovered. A sample of one of the sites has been sent for radiocarbon dating.

Bellair North Bog, Bellair Works
Bellair Works covers 730ha of bog and is located north of Lemanaghan, approx. 3.5km south of the town of Moate. This Works straddles the Offaly–Westmeath county boundary (Offaly 6" sheet 7 and Westmeath 6" sheet 36). It is made up of two bogs, Bellair South and Bellair North. Bellair South was surveyed in 1996 and produced ten sites; Bellair North was surveyed in 1997 and produced seven sites.

In recent years most of the peat extraction in Bellair North Bog has been restricted to the eastern portion of bog, where moss peat is produced. Surveying conditions were very difficult and the visibility of sites was limited by vegetation over much of the bog. The survey identified seven sites, mostly scattered along the southern side of the bog. The sites are insubstantial, consisting of stakes and small deposits of worked and unworked wood.

Boora Works
Boora Works is comprised of a series of bogs north and south of the road between Tullamore and Cloghan in County Offaly. In 1997 the bogs of Noggusboy, Falsk, Derries, Turraun, Pollagh, Oughter, Roscore and Killaranny to the north of the road were surveyed, as well as Galros Bog to the south. Four of the bogs produced archaeological sites and these are described below. Although there were no sites identified in the other bogs at the time of the survey, this does not preclude the finding of sites in the future as peat extraction continues.

Derries Bog
This large bog is situated between Falsk and Turraun Bogs and south of the Grand Canal. In the main part of the bog, where the drains are orientated north–south, no archaeological sites were identified. At the north-west corner of the bog there is a small extension running off towards the Grand Canal.

Large amounts of natural wood in the peat in this area made the identification of sites very difficult. Despite this, six archaeological sites were recorded, including three toghers and deposits of worked and unworked wood. The toghers are mostly constructed of longitudinal roundwoods with some brushwood. One of the sites produced toolmarks which may have been produced with a stone tool. A sample from one of the sites has been sent for radiocarbon dating.

Roscore
This is a small bog located between Oughter and Killaranny Bogs. The survey identified an archaeological complex and four sites scattered throughout the bog, including one trackway of dense brushwood and roundwoods.

An archaeological complex measuring 35m x 20m with a minimum of fourteen archaeological sites is located on the northern side of the bog. It is only possible to classify a small number of the exposures of those sighted. Most of the wood is in dense, complex arrangements which make it difficult to discern individual sites. The highest drain face has stratified horizons of wood from the field surface down 1.2m and continuing below the base of the drain. A number of cuttings were opened in the area to investigate the sightings. These showed that the density of wood continued below the surface of the bog, with planks, roundwoods, brushwood, hurdles and twigs used. These form a variety of constructions, including trackways and a wooden platform. An oak roundwood found close to one of the sites has been dated by dendrochronology to shortly after 1000 BC. These sites are located over 0.5km from the nearest dryland and form one of an increasing number of Late Bronze Age complexes.

Killaranny
This bog, the easternmost in the northern half of Boora Works, is located 1km south of the village of Rahan. Four sites were identified scattered throughout the bog. One of the sites was a single sighting of a hurdle trackway. This may be the last remains of a much longer site which was reported in the early 1990s and ran north-east/south-west on the western side of the bog. The three other sites consisted of two single isolated pieces of worked wood towards the centre of the bog and a deposit of leather shoes probably dating from the late 19th century AD.

Galros
This bog is in the southern half of Boora Works and is located 4km north of Birr on the eastern side of the road to Cloghan. Four sites were identified distributed throughout the bog. Three of these are single pieces of worked wood and the fourth a brushwood and roundwood trackway located towards the east of the bog.

Frenchgrove crannóg, Co. Mayo
During the summer of 1997 a crannóg was reported during land reclamation in an area of bog which had initially been drained by the Office of Public Works 20 years ago. During this first stage of drainage a logboat was recovered in the field approx. 50m from where the crannóg was later identified. The site was reported to National Monuments and the IAWU was requested to carry out an assessment.

The site is visible as the tops of palisade posts which can be traced to define a roughly circular area measuring 21m x 22m. An area 8.5m long, 4.5m wide and up to 0.9m in depth had been machine-excavated within the palisade. The upcast material contained large timbers, brushwood, large amounts of bone, cut antler, sand and stone. The timbers consisted of 22 large worked trunks and five split timbers. Two of the split timbers have a series of mortices and probably represent base-plates. The other three timbers have extremely long tenons protruding from each end.

A two-day project to reinstate the site was undertaken. However, it was not possible to process the material in that time. The site was planned, records were taken of the disturbed material, sections were drawn and sieving of the spoil-heaps was started. A range of artefacts was retrieved, including fragments of rotary querns, a fragment of metal, whetstones, flint flakes and a piece of a wooden vessel.

A further week’s work is planned at the site in 1998 to complete the reinstatement by sieving the spoil-heaps to retrieve artefacts, faunal and palaeoenvironmental material. The split timbers are to be conserved and the remaining timbers reburied within the site. The water-level in the surrounding peat is to be monitored to ensure the protection of the site.