1
Introduction
During the monitoring of topsoil removal as part of the Lough Mask Regional Water Supply Scheme Stage III under licence 01E0314, a deposit of burnt sandstone was identified at the edge of a zone of peat in the townland of Carrowcor, Co. Mayo (Guinan 2002 and 2003a, 2003b). This site was designated Carrowcor II (Figs. 1&2).
No surface evidence to indicate the presence of this site was visible prior to the commencement of development works in the area. After discovery, the site was fenced off and the zone of archaeological interest protected. Cleaning and an initial investigation were conducted to determine the nature and extent of the archaeological deposits.
As the site had been uncovered during works, and lay within the pipeline wayleave, a decision was made to excavate it under a licence granted by Duchas (excavation licence 01E1081) in the autumn of 2001 (Appendix 1).
Geographical location
The site was situated c.76m OD, on the side of a third class road c. 2.3km from Bekan village and c. 10km from Ballyhaunis town in south Co. Mayo (Figs. 1 and 2). GPS co-ordinates were obtained from Mayo County Council’s GPS unit. The site is located at 141508.67 (easting),
278490.73 (northing).
The surrounding landscape is one of undulating pasture-land interspersed with low-lying zones of deep peat. The environment around the site today is mainly pastoral, but contains plants associated with drier and more disturbed habitats, probably resulting from modern drainage activities (McClatchie 2002).
Archaeological Background
The townland of Carrowcor (124 acres) is one of 45townlands in the civil parish of Knock. No fulachta fiadh were recorded from Carrowcor or the immediate neighbouring townlands prior to this work. However, during monitoring on the Lough Mask Regional Water Supply Scheme Stage III (Guinan 2002 and 2003a), a fulacht fiadh had been discovered 30m west of Carrowcor II. This site was designated Carrowcor I and was excavated under separate licence (01E0680) (2003c and 2004).
This monitoring also resulted in the discovery of six previously unrecorded fulachta fiadh in adjoining townlands relatively close to the two sites in Carrowcor. The first of these fulachta fiadh was discovered and excavated in Bekan townland 01E0679 (Guinan 2003d and e), c.2.2km east of Carrowcor. A second fulacht fiadh was recorded during monitoring, in a road cut pipe trench, also in the townland of Bekan c.3.2km east of Carrowcor (Guinan 2002). Two more sites were discovered and excavated in the townland of Cloonbulban (01E0681) 2.8km to the south-east (Guinan 2003f and g). In the nearby townland of Cloontumper, 3.4km to the south-east, two additional fulachta fiadh were recorded. One of these sites (Cloontumper I) was discovered as a spread of burnt sandstone and charcoal in ground disturbed during the reinstating of pipeline wayleave. In the same field just outside the pipeline wayleave, c. 20m to the west, a second possible fulacht fiadh (Cloontumper II), with visible surface remains, was discovered. This extant monument is a roughly semi-circular shaped mound c. 0.5m high.
The only recorded monument in the townland of Carrowcor is an enclosure (MA102:013) located 200m north of the excavation site. In the adjoining townland of Lissaniska there are six recorded enclosures (MA092:066; 067; 068; 069; MA102:014 and 015). A number of other prehistoric sites are known from the wider area (Comer and O’ Muraile 1986). One of the most notable monuments is a Bell Barrow located c 3km to the south-east in Belesker townland (MA102:051). A wedge tomb in Greenwood Td (MA092:074) is located 3.3km to the north-east (De Valera & O’ Nuallain 1964, Sheehan 1987-88, Guinan 2001a, 2003c). However, there is a complete absence of any recorded monuments within a 3km radius, south and south west of the excavation at Carrowcor. This in part may be explained by the boggy nature of the land in the area. It is possible that this area was occupied by zones of open water or a lake in prehistory as extensive deposits of marl were encountered during monitoring.
A number of finds of Bronze-Age date have been recorded from the environs. These include a hollow wooden tube, bound with bronze ribbon, from a bog in Bekan townland and a dugout canoe has been recorded from Bekan Lake. South-east of Carrowcor a bronze socketed spearhead (NMI find no. 1983:66) was found in Bracklagh townland in 1983 (Kelly, 1986, 34).
The Excavation
The site consisted of an irregular spread of burnt sandstone within a rich charcoal matrix. It was excavated from a base line established along a 0.5m baulk set out across the centre of the burnt spread, parallel to the Bekan/Barneycarroll road. An area 10.5m north/south by 13m east/west was excavated up to the limit of the acquired pipeline wayleave (Fig 3). Excavation showed that the site extended beyond the wayleave acquisition line to the south where a substantial area of the site remains unexcavated (see note on reinstatement p.25).
The site was initially de-sodded and cleaned up to the limits of the wayleave acquisition line (Plates 1-4). After initial site work it became apparent that the site had been subjected to modern agricultural disturbance caused by land reclamation and intensefurrow activity.The northern edge, nearest the Barneycaroll/Bekan road, was bounded by a deep field drain and disturbed by the local group water scheme, whose pipe was laid in the area.
The Stratigraphy of Carrowcor II, (Figs. 3-9, Plates 1-14)
Sod (C1) consisted of a dark brown silty clay, 0.05m in depth which overlay a mid-brown clay topsoil (C2) with occasional fine pebble inclusions ranging from 0.15m-0.4m in depth. This topsoil sealed all archaeological strata (Plate 1).
Topsoil was removed to reveal a redeposited layer of a compact, mixed, brown and yellow clay with moderate stone inclusions (C3). This deposit ranged in depth from 0.02-0.4m. This episode of redeposition was the result of land reclamation which the land owner indicated took place in the early 1980’s (Figs 7-9 Plate 1).
Beneath this zone of disturbance the original pre-reclamation sod line was discovered (C4). This consisted of a very compact mid-brown layer of fibrous roots in clay c. 0.03m in depth. This was underlain by the pre-reclamation topsoil (C5) which was a compact greyish brown clay with occasional soil inclusions. This was 0.1-0.15m in depth. Context 6 which underlay this original topsoil was a dark greyish brown clay (Figs. 3, 7 and 8, Plates 8-11) The layer was 0.12m deep. It had moderate stone inclusions 50% of which consisted of burnt sandstone. The layer was mixed - a result of ploughing disturbance - and represented the interface between the original topsoil (C5) and the burnt mound proper (C7).
A low mound of burnt sandstone within a black peat and charcoal matrix (C7) was exposed immediately below (C6) (Figs. 3 and 7-9 Plates 5-6 and 9-13). This compact deposit was largely composed of burnt sandstone cobbles (50-200mm in diameter) but also contained unburnt pebbles. The surviving mound which ranged from 0.15-0.27m in depth was heavily disturbed by furrow activity. It measured 6.2m north/south by 6m. A substantial area of the mound which extends to the south beyond the excavation limits, remains unexcavated.
The burnt mound was heavily disturbed by a series of seven cultivation furrows (C14) (Figs. 3-7, Plate 9). These generally ran north/south or east/west indicative of cross ploughing. The furrow fill varied depending on the material they cut through. In general the fill (C14A) comprised a mix of burnt sandstone, charcoal, lumps of natural boulder clay, marl, topsoil and peat. The furrows averaged 0.3 – 0.1m in width while they ranged in length from 1.3m-3m. The depths ranged from 0.10m to 0.15m. They were generally U-shaped in profile and cut through the burnt mound and the underlying marl into the boulder clay (C10) (Plate 9).
Excavation revealed the mound of burnt sandstone (C7) was underlain by an extensive deposit of marl (C8), a natural lacustrine deposit (Figs. 4, and 7-9, Plates 7-13). The cream coloured marl contrasted with the black charcoal filled furrows which cut into it. The marl covered the entire area of the excavation and was noted extensively in the vicinity during topsoil stripping and subsequent pipelaying. The deposit was extremely wet underfoot and whiter in colour towards the south-western side of the site. Frequent snail shell inclusions were visible throughout this deposit. It measured an average of 0.1m in depth but varied greatly across the site.
Marl (C8) was underlain by a deposit of mid-brown peat (C11) (Figs. 5 and 7-9, Plates 5-6 and 9 and 12-13). This natural peat growth varied in depth from 0.06 – 0.1m in depth and covered an area of 7.5m by 4m. It overlay compact light grey boulder clay (C10) a natural glacial deposit which underlay the entire area and contained occasional cobble inclusions (Fig. 6, Plates 14 and 15).
Beyond this basic stratigraphy a number of other contexts were identified which illustrate the extensive nature of post depositional disturbance to which the site had been subjected. At the south-western fringe of the site an isolated deposit of gravel with some grey clay (C9) covering an area of 1.7m north-northwest/south-south-east by 1.2m was identified.This deposit was 0.06m–0.1m deep and represented material associated with land reclamation.
Another disturbed context associated with land reclamation was (C13), a compact grey silty sand with frequent stone inclusions (Fig. 7). This occurred in two separate deposits at the south-western and south-eastern ends of the site and was 0.07m in depth.. Deposit 1 located in the south-western part of the site measured 3.3m by 2.5m in area. Deposit 2 located in the south-eastern part of the site measured 2.5m by 2.5m in area. Underlying Deposit 1 was a disturbed mid-brown very fine peaty clay (C12), which lay in the south-western part of the site on the natural boulder clay (C10) (Figs. 3 and 7 Plates 8 and 9). It covered an area 3.2m north-south by 2.08m and was 0.15-0.2m deep.
Context 15 an irregular featured was half-sectioned (D-D1) (Fig 4), revealing a shallow natural depression 1.5m north/south by 2.2m with a maximum depth of 0.2m. This depression was filled with a dark brown peat with coarse pebble inclusions (C15A) (Fig. 4).
Context
/Type
/Description
/Munsell
/Interpretation
1 / Deposit /- Sod
- Dark brown silty clay
- Litter layer
- Depth: 0.05m
Brown / Natural deposit. Overlay and sealed entire site
2 / Deposit /
- Topsoil
- Mid-brown clay
- Depth: 0.15-0.4m
- Infrequent stone inclusions
Brown / Natural deposit. Overlay and sealed entire site
3 / Deposit /
- Redeposited, mixed, brown & yellow clay
- Depth: 0.02-0.4m
- Moderate stone inclusions
- Compact
Yellowish brown / Evidence of reclamation circa 1985
4 / Deposit /
- Original sod line
- Layer of fibrous root and clay
- Mid- brown
- Depth: 0.03m
- Very compacted
Brown / Pre- reclamation sod line
5 / Deposit /
- Original topsoil
- Greyish brown clay
- Depth: 0.1-0.15m
- Compact
- Occasional stone inclusions
Brown / Pre- reclamation topsoil
6 / Deposit /
- Dark greyish brown clay
- Area: 10m east/west by 5m
- Depth: 0.12m
- Moderate stone inclusions 50% burnt sandstone
- Disturbed
Dark greyish brown / Interface layer between topsoil and burnt mound.
Mixed layer resulting from ploughing disturbance
7 / Deposit /
- Burnt stone in black peat and charcoal matrix
- Area 6.2m north/south by 6m
- Burnt sandstone cobbles
- Depth: 0.15-0.27m
- Extends beyond wayleave
- Includes unburnt pebbles
- Disturbed by furrow activity
Black / Heat shattered sandstone in a black charcoal and peat matrix fulacht fiadh material
8 / Deposit /
- Marl
- Cream
- Whiter at south-western edge of site
- Frequent snail shell inclusions
- Very wet deposit
- Average depth: 0.1m but varies greatly across site
Very
Pale Brown / Natural lacustrine deposit which underlay the burnt mound.
9 / Deposit /
- Grey clay
- Area 1.7m north-northwest/south- southeast by 1.2m
- Depth: 0.06-0.1m
- Numerous (70%+) well rounded, well sorted pebbles
- Located in the south-western part of the site
Grey / Redeposited gravel possibly associated with land reclamation
10 / Deposit /
- Grey compact boulder clay
- Natural subsoil
- 15% very angular cobble inclusions
- Larger rocks also present
Light Grey / Natural glacial deposit underlying the entire area
11 / Deposit /
- Peat
- Mid-brown
- Depth: 0.06-0.1m
- Area 7.5m east/west by 4m
- Sterile
- Largely confined to southern side of site
Brown / Natural peat growth generally underlying burnt mound and marl deposit
12 / Deposit /
- Very fine peaty clay
- Mid-brown
- Area 3.2m north/south by 2.08m
- Depth: 0.15-0.2m
- Confined to the south-western corner of the site
Brown / Natural deposit overlying boulder clay
13 / Deposit /
- Redeposited grey silty sand
- Compact with frequent stone inclusions.
- Resting above (C12)
- Depth approx: 0.07m
- 2 deposits one in the southwest (3.3m by 2.25m) and a second in the southeast (2.5m by 2.5m)
- Associated with land reclamation
Dark greyish brown / Redeposited material resulting from land reclamation in the 1980’s
14 / Cut /
- Furrows
- Cuts through burnt stone
- Orientated north/south or east/west indicative of cross ploughing
- 7 identified
- Cuts through burnt stone (C7), marl (C8) and into boulder clay (C10)
- U- shaped profiles
14A / Deposit /
- Length: 1.3-3m
- Width: 0.3-1m (varies)
- Depth: 0.1-0.15m
- Furrow fill
- Comprised a mix of burnt sandstone, charcoal, lumps of natural boulder clay, marl, topsoil and peat.
15 / Natural hollow /
- Irregular
- Shallow
- Area: 1.5m by 2.2m
- Depth: 0.2m
15A / Deposit /
- Fill of natural depression (C15)
- Dark brown peat
- Area 1.5 north/south by 2.2m
- Depth: 0.1–0.2m
- 25% poorly sorted coarse pebble inclusions
Brown / Fill of natural depression
Table 1
Context List from Carrowcor II
Archaeobotanical Analysis
During the course of the excavation a number of samples were taken from various contexts for archaeobotanical analysis. Four samples from the fulacht fiadh were subsequently submitted for analysis. This work was undertaken by Meriel McClatchie, Archaeological Services Unit, Department of Archaeology, University College Cork.
Methodology(extract from McClatchie 2002).
The archaeobotanical material was extracted from each soil sample using a combination of flotation, wash-over and wet-sieving techniques. A combination of these techniques is the most suitable method for the recovery of material as the processes cause the least amount of damage to fragile plant remains and are also effective in recovering small weed seeds.
The soil sample is placed into a bucket and soaked in water in order to disaggregate the deposit. The length of time allowed for the soaking of each sample is dependent upon the cohesiveness of the deposit. The water, including the flot, (Flot is the material that floats and is suspended in the water, such as seeds and charcoal), is then poured through a graded bank of sieves (the wash-over technique) containing mesh measuring 1mm, 500µmm and 250µmm, leaving the residual material that does not float at the bottom of the bucket. This process is repeated until no more material floats to the top of the water. The residue is then collected by wet-sieving which involves it being placed into a 2mm sieve and washed thoroughly in a concentrated flow of water using a hose. This method recovers denser organic material such as nuts and bone.
The scanning, sorting and subsequent identification of the archaeobotanical material in all samples is carried out using a Wild 8 zoom stereo-microscope, with magnifications ranging from x6 to x50. Each sample is scanned in order to extract the archaeobotanical material. The seeds are then sorted into general groupings on the basis of visual comparison of their morphological features. The seeds were identified by comparison to reference material in the U.C.C. Archaeology Departmental collection of modern diaspores and the drawings from various seed keys (Anderberg 1994; Beijerinck 1947; Berggren 1969; Berggren 1981; Katz et al. 1965). Some of the seeds were distorted or fragmented and identified to genus level only. The identified taxa are listed by context in the order that they appear in Flora Europaea (Tutin et al. 1964-83).
Plant remains present
Four soil samples from a fulacht fiadh at Carrowcor II were submitted for analysis. Non-wood plant remains were not recovered from any of the examined deposits. The presence of substantial quantities of land snails in a number of deposits (Table 2) may represent organic or rotting material that would have attracted the land snails. No botanical evidence was recorded to reveal activities at the fulacht fiadh.
Conclusions
A low level and rather narrow range of flora was recovered from deposits. Evidence for open, damp environments was regularly identified. There is likely to have been woodland available locally, as evidenced by the recovery of flora associated with woodland margins. The absence of charred plant remains besides wood is another indicator that wood was readily available as a fuel source during the various periods of activity, as the remains that could be expected from burning turves or other vegetation were not identified.
The Samples
The following is a summary of the context and content of the four samples which were submitted for archaeobotanical analysis.
Sample no. 3 was taken from context 8, marl located under topsoil at the edge of the burnt mound and contained charred wood and land snails.
Sample no. 4 was taken from the main mound. It consisted of burnt sandstone within a charcoal matrix (C7). It contained charred wood.
Sample no. 8 was taken from the marl layer (C8) underlying the burnt mound (C7). It contained charred wood and land snails.
Sample no. 10 was taken from a peat deposit (C11) which underlay the burnt mound (C7). It contained charred wood, anaerobically preserved wood and land snails.
Site / Townland / Samplenumber / Charred
seeds / Charred
wood / Anaerobically
preserved
seeds / Anaerobically
preserved
wood / Anaerobically
preserved
vegetative material / Anaerobically
preserved
mosses / Anaerobically
preserved
beetles / Land
snails
01E1081 / Carrowcor II / 3 / . / ◊ / . / . / . / . / . / ◊
Carrowcor II / 4 / . / ◊ / . / . / . / . / . / .
Carrowcor II / 8 / . / ◊ / . / . / . / . / . / ◊
Carrowcor II / 10 / . / ◊ / . / ◊ / . / . / . / ◊
◊ = present
Table 2
Organic material recorded in deposits from 01E1081
Species identification of charcoal samples (extract from O’ Carroll, 2003)
Introduction