Charcoal analysis, Killeen Castle, Co. Meath

This report discusses the analysis of charcoal from five sitesexcavated at Killeen Castle, Co. Meath, by Christine Baker. Thecharcoal comes from a variety of contexts, including ditches,kiln fills, furnaces and burnt spreads. The aim of the charcoalanalysis was to provide material for radiocarbon dating, toexamine trends in fuel selection for kilns, furnaces and fires, andto use suitable samples for environmental reconstruction. It wasalso hoped to compare charcoal from different periods to seewhether differences in woodland cover occurred. The overallresults are presented first, followed by the site results.

METHODOLOGY

Sampling and processingThe samples were taken on site as bulk soil and were processedby flotation, whereby each sample was soaked in water inorder to suspend the carbonised material; this was then pouredoff and trapped in a sieve (mesh size 300µm). This ‘flot’ (i.e. thefloated material) was dried and stored in sealed plastic bags.Thomas Cummins, Ciara Griffin and Frank Zak processed thesamples. The samples were all subsequently scanned by theauthor, and charcoal samples suitable for identification andradiocarbon dating were selected.

Identification of the charcoalEach piece of charcoal was examined and orientated firstunder low magnification (10x–40x). They were then brokento reveal their transverse, tangential and longitudinal surfaces.Pieces were mounted in plasticine and examined under abinocular microscope with dark ground light andmagnifications generally of 200x and 400x. Each taxon orspecies has anatomical characteristics that are particular tothem, and these were identified by comparing their relevantcharacteristics to keys (Schweingruber 1978; Hather 2000;Wheeler et al. 1989) and to reference material supplied by theNational Botanic Gardens.

Quantification of material The recommended number of fragments to identify from eachsample in a temperate environment is 100 (Keepax 1988),which was the minimum number that was aimed for on thissite. Given the nature of archaeology, frequently there are

samples where there are not 100 fragments present, forexample from post-holes or small deposits. In these cases, allfragments greater than 2mm were identified.

ENVIRONMENTAL RECONSTRUCTION FROMARCHAEOLOGICAL CHARCOAL

It is considered that fuel will be gathered from as close to thesite as possible, the so-called ‘Principle of Least Effort’(Shackleton and Prins 1992), and therefore archaeologicalcharcoal can reflect the surrounding environment. This is notalways the case, however, especially in medieval times, whentimber could have been transported onto the site from otherareas. Charcoal from certain contexts is more suitable forenvironmental reconstruction than others. For example, long-term deposits should give a good picture of fuel use on site.These could be refuse dumps, middens or areas such as slot-trenches or post-holes that have been left open, allowingcharcoal to gradually accumulate in them, presumably fromactivity on the site. In contrast, charcoal from hearths or kilns ismore likely to represent the last episode of use and probably willnot show long-term patterns of fuel consumption so clearly.There are, of course, other advantages to sampling shorter-termdeposits, as they can provide important information on thewood species selected for construction and the fuel typesselected for specialised functions such as iron-working.

TOTAL RESULTS FROM ALL KILLEEN SITES

Thirty-four samples from the five sites were analysed: threefrom site D, five from site G, three from site H, nine from site

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Fig. 8.1—Total charcoal identifications from all Killeen Castle sites (weight).

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D and fourteen from the castle ditch site. Ten taxa or woodtypes in total were identified: alder (Alnus), ash (Fraxinusexcelsior), blackthorn (Prunus spinosa), wild/bird cherry (Prunusavium/padus), wych-elm (Ulmus), hazel (Corylus avellana), holly(Ilex aquifolium), oak (Quercus petraea/robur), pomaceousfruitwood (Pomoideae) and willow (Salix sp.). The weight ofthe material was dominated by ash, followed by oak (Fig. 8.1).

When one examines the fragment counts, the picture isquite different (Fig. 8.2). The material is in this case dominatedby oak, followed by ash and alder. It is important to interpretboth weight and fragment counts, as sometimes they candiffer. This is because certain species such as oak are quitedense and will weigh more than others, while some speciesmay fragment more easily than others.

The total number of samples analysed from Killeen Castlewas 34. Ash was present in 21 of the samples, while hazel andoak were both found in eighteen. Blackthorn was identified inthe fewest number of the samples, at only one (Fig. 8.3).

The site count, along with the sample count, will showhow widespread the different taxa were. Alder, ash, hazel andoak were identified on all five sites, while trees such as thepomaceous fruitwoods and willow were present on four of thesites. Cherry was present on three sites, elm and holly on twoand blackthorn on only one (Fig. 8.4).

SITE A (05E0303)

The site consisted of pits and post-holes and dates from theearly Bronze Age. Charcoal from three pits was examined, thecontents of which resembled fulacht fiadh material. Thematerial all comes from phase 1 of the site.

ResultsFive taxa were identified from site A: alder, hazel, ash, oak andelm. Ash was the most frequently identified, followed by hazeland elm. The material was quantified using fragment countsand weight (Fig. 8.5). The fragment counts and weight fromsite A were very similar.

Sample 4, F16: Alder, ash, oak, elm and hazel wereidentified from this pit; ash and elm were the main taxarepresented. The ash, elm and oak all had fast growth. Someinsect holes were present in the material.

Sample 11, F26, C2: Ash and hazel only were identified inthis pit, with ash being the most frequent. Both species wereof medium growth; the ash growth was very even.

Sample 19, F13: From this pit hazel, ash, elm and alderwere identified. Hazel and ash were the most frequentinclusions. The ash grew quite fast, while the hazel grew at amore medium rate.

The archaeology of Killeen Castle

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Fig. 8.3—Sample counts of total charcoal from Killeen Castle.

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DiscussionThe results were similar from the three features. Hazel and ashwere identified in all three samples, indicating that they grewin the local area. Charcoal has been identified from similartypes of pits in Barnageeragh (04E0209), Co. Dublin (dated tothe early Bronze Age), and Cooksland (02E0641), Co. Meath.The latter were dated to the late Neolithic–early Bronze Age(O’Donnell 2007a). All taxa identified at Killeen Castle werealso identified at Barnageeragh. In contrast, however, thepomaceous fruitwood type was also identified at Barnageeraghbut was not found at Killeen Castle. From Cooksland, Co.Meath, all five taxa were again identified, and pomaceousfruitwood was also present. The excavator has described thematerial in the pits as reminiscent of material found in fulachtafiadh. The high number of excavated fulachta fiadh in Ireland inrecent years has led to a considerable amount ofenvironmental analysis of this rather enigmatic monumenttype. Recent work from along the Gas Pipeline to the West hasshown that, according to the charcoal evidence, these sitestend to be sited on the margin of dry and wetland areas, withhigh levels of oak, hazel, ash and alder (O’Donnell 2007a). Thetaxa identified from Killeen Castle site A are all frequentlyidentified from Irish fulachta fiadh.

SITE G (05E0539)

Site G was a medieval rectilinear enclosure. The radiocarbondates from the charcoal were very similar, indicating that thecontexts examined by the author were contemporary, datingfrom the thirteenth to the fourteenth century. Material wasexamined from various features such as ditches and pits.

ResultsSeven taxa were identified from site G: alder, hazel, ash,pomaceous fruitwood, cherry, oak and willow (Fig. 8.6). Ashand cherry were the most frequently identified taxa. Theweight and fragment counts differ slightly (Figs 8.6 and 8.7);

the weight shows ash, pomaceous fruitwood, cherry and oakas being the main taxa on site, while the fragment counts showash and cherry to be the most common. The features from siteG come from different phases within the site.

Sample 5, F15, phase III: Charcoal was identified from thisditch fill, which was the most charcoal-rich context examinedby the author from site G. Six of the seven wood typesidentified on site were present in this fill, but alder was notpresent. The main types were cherry and oak. Some insectholes were present in the material, indicating that decaying,dead wood had been burned.

Sample 7, F40, phase IC: Only one small fragment of ashwas identifiable from this lintel drain.

Sample 19, F54, context 1, phase III: Three fragments onlyof alder were identifiable from this shallow cut, in whichmedieval pottery was found.

Sample 31, F95, phase IC: Oak, alder, ash and cherry wereidentified from this pit. The main species were ash and cherry.The material was between at least three and five years oldwhen it was cut.

Sample 37, F4, phase IB: Pomaceous fruitwood only wasidentified from this shallow cut.

Discussion The material from Killeen site G has a variety of trees, whichcould suggest random collection of firewood. The charcoalresults were very similar to the nearby site H, and also to siteA. Too little material from F40, F54 and F4 was available toprovide comparisons. Pomaceous fruitwood, willow and hazelwere present in F15 from phase III but were not identified inF95 from phase IC. Alder was present in F95 but not in F15.The charcoal is probably all the remains of domestic fires, asthere was no clear preference for specific fuels such as oak,which is frequently used for crafts like metal production. Thesite was bordered by a stream, which would have provided anideal situation for alder and willow to grow.

Analysis of the charcoal

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SITE H (05E0415)

Site H consisted of a field system associated with a D-shapedenclosure. Three phases were noted on the site: phase Iconsisted of large ditch features, phase II consisted of pits andassociated activity, and phase III consisted of isolated drains andpits. The samples date from the early medieval period.

ResultsCharcoal from three samples was analysed from site H. Six taxawere identified from the samples: alder, hazel, ash, pomaceousfruitwood, oak and willow (Fig. 8.8). The fragment count andweight from the pieces were low, but oak and willow were themost frequently identified taxa on site.

Sample 1, F21: Pomaceous fruitwood and willow wereidentified from this linear feature.

Sample 2, F55: Alder and oak were identified from thisbowl pit. Insect holes were present, indicating the use ofdecaying wood. The presence of oak and alder may suggest thatthe pit was used for charcoal production or metalworking.

Sample 7, F40: Hazel, alder, ash and oak were identifiedfrom this enclosing ditch.

Discussion The charcoal results from site H are very similar to those fromsite G, indicating that the same types of trees survived from theearlier site H to site G, which was utilised up to 200 years later.

Site G is bordered by a stream while site H was located onhigh meadow ground with good drainage, so it is interesting thatthe wetland trees willow and alder were identified from bothsites. Feature 21 post-dates the other features, as it dates from themedieval period while the other two date from the earlymedieval period. Pomaceous fruitwood and willow only wereidentified from F21, and they were not present in any of theother features. In contrast, alder and oak were identified fromF55, while alder, oak, hazel and ash were identified from F40.

SITE D (05E0949)

The main features on site D were kilns, furnaces andinterlinking ditches and drains. Charcoal was analysed fromnine samples from this site, which included six contexts, suchas furnaces, kilns, ditches and pits.

ResultsNine taxa were identified: alder, hazel, ash, holly, pomaceousfruitwood, wild/bird cherry, blackthorn, oak and willow (Fig.8.9).

Sample 9, F40, C1E: This sample from a furnace featureconsisted mainly of oak, with some hazel.

Sample 10, F40, C2: This sample came from a charcoal- andslag-rich spread, part of F40. Hazel, oak, ash and holly wereidentified; the main species identified was oak, as in sample 9.It is likely that the charcoal in this feature was mainly a resultof burning activity relating to slag, but other species could havegot mixed into the fuel and subsequently spread out.

Sample 13, F54, C1: This feature was a possible kiln. Oakand alder only were identified from here, and alder was themain wood represented. Insect holes were present within thealder, indicating the use of decaying wood. This was the firstphase of burning within the kiln.

Sample 14, F54, C2: This was the second phase of burningwithin the kiln. Alder, cherry, oak and hazel were identified,and oak was the main wood present. Insect holes were notedin the hazel.

Sample 15, F61, C1 west: This was a spread associated witha charcoal-rich kiln. A small amount of oak only was identifiedfrom here.

Sample 16, F61, C1 east: A far greater variety of taxa wereidentified from this sample of the spread. Oak, ash, willow,blackthorn and alder were present. It is likely that this spreadrepresents accumulated charcoal and therefore would be moresuitable for the purposes of environmental reconstruction.


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Sample 19, F68: This was the fill of a rectilinear pit. Fourtaxa were identified: hazel, oak, pomaceous fruitwood and ash.The main species identified was oak, which consisted of smallfragments of slow to medium growth.

Sample 22, F75: This was from a pit associated with F62. Itmay have been a furnace/fire bowl/hearth. Oak and alder onlywere identified from here, the main species present being oak.

Sample 23, F1: This sample was from a curvilinear ditchfill. One fragment of oak only was identified.

Discussion While the site is phased, all but sample 23 (F1) come fromphase IV. F1 is part of the earlier phase 1 of the site. As onlyone fragment of oak was identified from here, it is not usefulto make comparisons between the phases.

Charcoal from five samples was analysed from contextsassociated with smelting (samples 9, 10, 15, 16 and 19 fromfeatures 40, 61 and 68 respectively). The material is clearlydominated by oak, both in weight (Fig. 8.10) and in fragmentcounts. Other taxa may have been introduced accidentally or,because much of the material comes from spreads around kilnsand furnaces, could be a result of general on-site burning. Thehigh levels of oak indicate that it was sourced nearby.

Bowl furnaces from early medieval sites excavated atKiltenan South, Co. Limerick, and Aghamore, Co. Meath,were probably used for smelting iron slag, and the charcoal wasdominated by oak. A possible furnace of similar date at DollasLower, Co. Limerick, also contained mainly oak. AtDoohylemore, Co. Limerick, a possible metalworking furnacecontained mainly oak (O’Donnell 2007a). This issupplemented by work from England, where results from 24sites associated with iron-smelting indicate that oak wasconsistently the dominant fuel from the early Iron Age to themid-medieval period (Gale 2003, 37).

The uses of charcoal in Europe can be traced back at least5,500 years. It was the smelting fuel of the Bronze Age and theIron Age. No other fuel was available to metalworkers that

could reach the temperatures necessary first to smelt the ore tomake a matte and then to raise the temperature of the broken-up and washed matter to the point where metal would melt andcould be cast (D. Kelly 2002, 3). McCracken (1977, 92) writesthat, ideally, the best charcoal for smelting comes from 25-year-old coppice oak, and in England the iron masters practisedcoppicing to ensure a continuous supply. An acre of coppicegave enough fuel to make a ton of iron every 25 years.Archaeological evidence indicates that iron-working wascarried out on almost every habitation site (Edwards 1990, 86).

When the charcoal results from the pits related to smeltingare contrasted with those from the cereal-drying kiln F54, itcan be seen that there is a much more even spread of taxa;although oak is still important, alder is more so (Fig. 8.11). Inthe author’s experience, when dealing with fuel from cereal-drying kilns one tends to identify a variety of taxa. This couldbe because charcoal from kilns may represent wattle that wasburnt by accident, which could be composed from a variety oftrees such as hazel or willow.

A variety of woods were identified from the early medievalkiln deposits in Charlesland (site D, 03E0146), but the mostcommonly used was oak (O’Donnell 2007b). Six taxa wereidentified at the early historic site of Kiltenan South, Co.Limerick (02E0666), while four taxa were identified atFlemingtown, Co. Dublin (02E0296) (O’Donnell 2007a).

CASTLE DITCH SITE (05E0414 EXT.)

The castle ditch site was characterised by substantialenclosures, and probably dates from the early medieval to themedieval period. Fourteen samples were analysed from thecastle ditch site.

Results Nine taxa were identified, with ash and oak being the mostsignificant (Figs 8.12 and 8.13). When one examines the


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metalworking, site D.

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weight graph from the site, ash appears to be extremelysignificant, followed by oak. These weights of ash are falselyhigh, however, given the high levels of ash from F31, thelimekiln. The fragment count gives a more varied picture, withash still being more significant but with oak, hazel and ash alsoimportant. Ash must have been used frequently on the site, asit was identified in ten of the fourteen samples, in comparisonto oak, which was present in only four. Hazel was identified inseven samples, while cherry was present in two.

Discussion The castle ditch site was divided into five phases, and charcoalhas been analysed from phases I–III. Phase I was the earliestsettlement of the site and included two ditches, which enclosethe probable early medieval settlement. Charcoal was analysedfrom ditch features 7 (C219), 49 (C7 and C65) and 13 (C2).Seven taxa were identified (Fig. 8.14), the most commonbeing alder. F49 and F7 were part of the same enclosing ditch.Only a small amount of cherry was identified from F7, whilea larger volume of burnt material was present in contexts 7and 65 of F49. Six taxa were identified in total from this ditch,probably the remains of a fire dump. Four taxa were identifiedfrom F13, three of which (cherry, hazel and ash) were alsopresent in ditch F49.

Phase II was characterised by the large curvilinear ditchF1, which probably dates from the Anglo-Norman period.

Charcoal was analysed from context 6 within F1 and also fromvent F58 of the triple-flued kiln F31. Ash only was identifiedfrom the kiln, while ash, hazel, elm and willow were present inthe ditch.

Medieval activity characterised phase III, including ditchesand structures. Charcoal was analysed from six differentfeatures. F31 was a limekiln fill, and high levels of ash onlywere identified from here. This compares well with thelimekiln from phase II, F58, where again ash only wasidentified. Calcined lime was essential for the production ofmortar for the building trade. A steady temperature of about800–900°C had to be maintained by the kiln operator in thelime-burner until the stone was burnt, without exceeding1150°C, when ‘overburn’ occurred. In England a variety oftaxa have been identified from Roman lime-burning kilns,including beech, poplar, oak, hazel, maple and hawthorn (Gale2003, 35–9).

Ash and holly were identified from a cereal-drying kiln(F76). Four taxa were identified from a rectangular cistern(F155), while three taxa were present in a stone-lined kiln(F11). Four taxa were identified from the large ditch F103.These included elm, which must have occurred near the sitein the medieval period. From a rubble stone deposit (F18)pomaceous fruitwood and oak were identified, oak being the


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main tree present. In total eight wood types were identifiedfrom phase III of the castle ditch site (Fig. 8.14). The mostimportant was ash, although this has elevated frequenciesbecause of its high levels in the limekilns. The next mostimportant was oak.

The material from the castle ditch site provides usefulinformation about the fuel available from the early medievalperiod through to the medieval period. Ash and hazel wereidentified throughout each phase, while alder, cherry, oak andpomaceous fruitwood were identified from both phase I andphase III. The charcoal identifications do not suggest anyparticular changes in woodland cover from the early medievalto the medieval period.

THE KILLEEN CASTLE LANDSCAPE THROUGHTIME

The charcoal record from Killeen Castle stretches from theearly Bronze Age to the medieval period. At site A, charcoalwas identified from the early Bronze Age. Five taxa wereidentified: alder, hazel, ash, oak and elm (Fig. 8.5).

The next chronological identifications come from theearly medieval period. Site H, site D and phase I of the castleditch site all date from this period. All taxa identified at site Awere also present on site H, with the exception of elm.Pomaceous fruitwood and willow, however, were present onsite H but not on site A. A larger variety of taxa (nine) wereidentified from site D, which is to be expected as more sampleswere examined. All taxa identified from the early Bronze Agesite A were present on site D, again with the exception of elm.On site D, in comparison to site H, pomaceous fruitwood andwillow were identified. In contrast, holly, cherry andblackthorn were also present. Phase I of the castle ditch site,dating from the early medieval period, also exhibited all thetaxa from site A, with the exception of elm. In comparison tosite D, cherry, pomaceous fruitwood and willow were present.

The total charcoal identifications from the early medievalperiod can be seen in Fig. 8.17. Nine wood types in total wereidentified from the early medieval period at Killeen Castle,with oak clearly dominating, which probably relates to thelevels of metalworking encountered on site D. Alder is the nextmost important. The identifications clearly show a variety ofsmaller shrub-like trees, such as blackthorn, cherry and holly.

The medieval period at Killeen Castle is represented in the

charcoal record from site G and from phases II and III at thecastle ditch site. A relatively wide variety of taxa wereidentified from site G (Figs 8.6 and 8.7), all of which wereidentified in the early medieval contexts at Killeen. All taxafrom phases II and III of the castle ditch site were also presentin the early medieval phase I, with the notable exception ofholly and elm. Therefore elm was present in the charcoalrecord during the early Bronze Age at Killeen Castle, and alsoduring the medieval period. The total taxa identified from themedieval period can be seen in Fig. 8.18. The dominating taxaare ash and oak, followed by cherry and hazel. The high levelsof ash from the medieval period relate to the limekiln F31 inphase II of the castle ditch site. The main difference betweenthe two periods is the higher levels of ash in the medievalperiod compared to the dominance of oak in the earlymedieval period. Elm is present in the medieval period butwas not identified in the early medieval counts. Blackthorn ispresent in the early medieval but not in the medieval. All thespecies identified from the early Bronze Age site are present inthe medieval period.

The charcoal identifications from the Killeen Castle siteprovide a valuable record of woodland cover in the area. Morediversity in taxa was noted in the early medieval and medievalperiods than in the early Bronze Age. This can be attributed inpart to fewer samples being analysed from the early BronzeAge, but probably also reflects an opening up of the landscapeduring the early medieval and medieval periods, with speciesthat need light to grow and would prefer woodland margins


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Fig.8.17—Charcoal from the early medieval period, Killeen Castle.


or hedges, such as cherry, blackthorn and hawthorn.Throughout each site, ash, hazel and oak were important, andit appears that they remained consistent from the Bronze Age.Oak and ash appear to have been the main canopy trees in thearea during all periods. The earlier site A was located on anorthern ridge, while the later sites lie almost 1.5km south ofthis. All taxa from site A were identified in the later periods;the main difference is the greater diversity of taxa during theearly medieval and medieval periods. The presence of similartaxa indicates similar soil conditions at site A and sites G, H, Dand the castle ditch. But 1.5km is not a great distance, andfirewood may have been gathered near the site A area for theother sites and vice versa. Site A’s more exposed location mayhave limited the species that could grow there.

O’Sullivan (1998, 62) notes that various sources ofevidence indicate that the early medieval landscape had onlyintermittent small woods, hedgerows and scrubby woodlandembedded within a highly managed agricultural landscape.This is corroborated in the Meath area by pollen analysis fromStewart (1996) at Moynagh Lough, which shows scrubbypatches of woodland and hedgerows during the early medievalperiod. The material from Killeen Castle fits and enhances thismodel, as it shows the presence of larger-canopy trees such asoak and ash but a significant rise in scrub, shrub and hedgerowtaxa, such as the hawthorn/apple/rowan type, cherry andblackthorn.

Charcoal deposits from early medieval contexts at site M,Knowth, Co. Meath, were extremely similar to those fromKilleen Castle, with trees and shrubs that were probablygathered from small woodlands and scrubs/hedges, such ashazel, ash, oak, cherry and the pomaceous fruitwood types(Johnston and O’Donnell 2008). The early medieval site ofCastlefarm 1, Co. Meath, yielded evidence for hazel,pomaceous fruitwood, alder, ash, willow, yew, oak and beech(Fagus sylvatica) (O’Donnell 2007b).

During the early medieval period woodland was beingrecognised as a valuable commodity, and one that required

protection. This led to its recognition in the eighth-centuryBretha Comaithchesa or laws of the neighbourhood. Trees wereclassified into four groups depending on the economic valueof the wood, calculated by its use as a structural timber, suchas ash or oak, or because of its dietary contributions, such ashazelnuts or apples. The classifications were ‘nobles of thewood’, ‘commoners of the wood’, ‘lower divisions of thewood’ and ‘bushes of the wood’. Trees like oak, holly and hazelwere considered ‘nobles of the wood’, while the lowestclassification (bushes of the wood) included bracken, bogmyrtle and gorse or furze. Fines were imposed on peoplecaught cutting branches or cutting at the base of the trees.These varied according to the classification of the tree, andincluded heifers and sheep (Kelly 1976).

By the early fourteenth century formal systems ofwoodland management were in operation in the vicinity ofAnglo-Norman Dublin. Results of wood analyses from BackLane have shown hazel underwood to have been on a coppicerotation cycle of between five and eight years (O’Sullivan1998). At Winetavern Street, where thirteenth-century post-and-wattle and brushwood waterfront structures wereexcavated, the preferred wood used was ash and hazel. ThereO’Sullivan (2000) noted evidence for the extraction ofunderwood at four, seven–eight and ten–eleven years.

Throughout the analysis of the Killeen Castle charcoal,each piece was examined to see whether there was anyevidence for woodland management. The craft ofwoodsmanship involves the management of woodlands for theproduction of timber, firewood and rods for assorted uses(Tierney 1998). During coppicing the stump sends up shoots,called spring, and becomes a stool from which an indefinitesuccession of crops of rods, poles or logs can be cut at intervalsof years. It is a very efficient and reliable way of establishing anew crop. Some woods are also self-coppicing, such as hazel(Rackham 2001). It is extremely difficult to determine thepresence or absence of any woodland management practices incharcoal fragments; characteristics to look out for include thefirst two to three rings being normally very wide, with asubsequent decrease in growth. Other features include verysimilar patterns of growth, or those which are extremelyregular. None of these characteristics were evident on theKilleen Castle material. Rather, the ring-width patterns weremore like those of naturally grown trees, with some decreasesand increases in growth in no evident pattern. The lack ofevidence for management from the charcoal fragments cannotdenote with any certainty, however, that management was nottaking place in the vicinity.


120

0

50

100

150

200

alde

ras

h

cher

ry

elm

haze

l

holly

oa

k

pom

aceo

us

willo

w

taxa

am

t. o

f fr

ag

me

nts

Fig. 8.18—Charcoal from the medieval period, Killeen Castle.


WOODLAND RECONSTRUCTION OF THEKILLEEN CASTLE AREA

Oak, ash and hazel were all important throughout the KilleenCastle identifications, and probably grew near the sites. Hazelwill grow as a scrub or as a tree, and it will grow in a varietyof conditions, but not in completely waterlogged areas (Ormeand Coles 1985). Ash can also be found near rivers, but willflourish best in nutrient-rich drier soils, with a good source oflight. Ireland has two native oaks, pedunculate (Quercus robur)and sessile (Quercus petraea). The pedunculate oak will grow inheavy, relatively wet lowland soils, where it will tolerateflooding. In contrast, the sessile oak prefers less fertile, acidicsoils (Beckett 1979). These three trees can all grow in wetteror drier soils (depending on the type of oak present) and soprobably denote a mixed environment in the vicinity ofKilleen.

Another large-canopy tree present in the area was elm,which was identified from the middle Bronze Age site A andthe medieval castle ditch site. Elms are large, deciduous treesthat reach a height of 40m and can live for up to 500 years(Hickie 2002, 77). The timber is tough and is characterised byinterlocking fibres that prevent cleaving and splitting (Galeand Cutler 2000, 264). It is extremely durable whencontinuously submerged. It appears that elm trees lasted in theKilleen area from the Bronze Age through to the medievalperiod. During the Neolithic, along with the rest of Europe,Ireland experienced a significant elm decline. This may havebeen a result of Neolithic farmers felling trees for agriculture,or may be a result of widespread Dutch elm disease (Pilcherand Hall 2004). Woodland records say that the tree wasvirtually eliminated in Ireland by the seventh century AD, andwas reintroduced in the eighteenth century (McCracken1977, 17). Charcoal analysis from a growing body ofarchaeological excavations (e.g. Kilgobbin (04E1373);O’Donnell 2005) has shown, however, that it does occur inIreland between the seventh century and the post-medievalperiod, and the charcoal from the medieval contexts at theKilleen castle ditch site adds further evidence. Pollen analysisfrom Moynagh Lough, Co. Meath (Stewart 1996), shows twoelm declines in the area during the Neolithic, followed by athird elm decline during the Bronze Age.

There is also evidence from Killeen for a number ofsmaller trees and shrubs that will grow in hedges or inwoodland margins. Two species from the Prunus genus wereidentified, Prunus avium/padus (wild/bird cherry) and Prunusspinosa (blackthorn). Wild cherry (Prunus avium) needs light togrow, on or near woodland margins and on light, well-drainedsoils (Orme and Coles 1985, 11). Bird cherry (Prunus padus)

occurs particularly in marginal forests and is generally solitary(Stuijts 2005, 142). Blackthorn grows in woodland where thecanopy has been opened, on woodland margins, in scrub andalong streams, where it may be found with alder. It does notsurvive under heavy shade (Orme and Coles 1985, 11). Thepresence of these species from the early medieval and medievalperiods at Killeen Castle may indicate an opening up of thelandscape during this time.

The Pomoideae group, a sub-family of the Rosaceae,includes crab-apple, wild pear, rowan/whitebeam andhawthorn. It is extremely difficult to separate these speciesthrough wood anatomy. Crab-apple (Malus sylvestris) tends tobe found on woodland edges (Hickie 2002, 55). Wild pear(Pyrus pyraster) is mostly found as an isolated tree (Stuijts2005). Rowan (Sorbus aucuparia) is a tough coloniser that cantolerate peaty soils and exposed conditions. It needs plenty oflight to thrive (Hickie 2002, 65). Whitebeam (Sorbus aria)grows up to 20m high and has a preference for limestone soils(Orme and Coles 1985, 11). Hawthorn (Crataegus monogyna)can thrive in all but the most acid of soils (Gale and Cutler2000). As wild pear is not a native Irish species, it is likely thatthe charcoal represents other types encompassed in thePomoideae group.

There are some definite indications that there was a watersource near the site in the form of a stream, river or dampwoodland. Ireland’s native alder is common or black alder(Alnus glutinosa). This tree prefers to grow in wetland areas, andcan often be seen in damp woodland or beside streams. Willowwill also grow in wet areas. The main Irish native willows aregrey willow (Salix cinerea), goat willow (Salix caprea) and earedwillow (Salix aurita).

The charcoal evidence from Killeen Castle indicates thatthe site was located near different woodland environments,with access to wet areas such as rivers or streams but also dryland. This is frequently the case with Irish archaeological sites,as logically people would need dry areas on which to live andwork as well as access to a nearby source of water for workingand cooking. The charcoal identifications show the presence oftaller-canopy trees such as elm, oak and ash, but also smallershrubs that will grow on woodland margins and as hedges, likecherry, blackthorn and hawthorn.

SUMMARY

Charcoal was analysed from five sites in the Killeen Castlearea, Co. Meath. The sites dated from the early Bronze Age tothe post-medieval period. Charcoal was examined fromvarious contexts, including ditches, kiln and furnace fills, pits,


121


fulachta fiadh-like material and charcoal spreads. Ten taxa orwood types were identified in total from the sites, with ash,oak and hazel being the most significant. Five taxa only wereidentified from the early Bronze Age site A, while a widervariety of taxa were present in the early medieval and medievalcontexts, indicating an opening of the landscape to allow treesthat need to grow in hedges and woodland margins toflourish. The Killeen Castle site offered access to both wetlandand dryland areas. A mixture of dead decaying firewood withinsect holes and fresh wood was used as fuel on each site. Themain tree related to metalworking in the area was oak, whichhas many parallels from other archaeological projects. Incontrast, a wider variety of species were present in contextsassociated with cereal-drying kilns. The charcoal from theearly medieval and medieval period compares very well withother Irish woodland studies from the same time.


91 91 11 11 4 4 elpmaS 31 31 62 62 61 61 erutaeF

Context 2 f w f w f w Alnus glutinosa L. Gärtner (alder) 0.3 4 0.08 3 Corylus avellana L. (hazel) 0.25 5 0.21 4 1.52 23 Fraxinus excelsior L. (ash) 1.74 40 0.49 4 1.95 35 Quercus spp L. Liebl (oak) 0.77 5 Ulmus glabra L. (elm) 1.24 23 0.92 11

* w = weight in grams; f = fragment count.

Table 8.1—Charcoal identification details from site A (05E0303).

Table 8.2—Charcoal identification details from site G (05E0539).

Table 8.3—Charcoal identification details from site H (05E0415).

Sample 5 5 7 7 19 19 31 31 37 37 Feature 15 15 40 40 54 54 95 95 4 4 Context 1 1 w f w f w f w f w f Alnus glutinosa L. Gärtner (alder) 0.11 3 0.01 1 Corylus avellana L. (hazel) 0.12 6 0.01 1 Fraxinus excelsior L. (ash) 0.52 15 0.03 14 Pomoideae L./Miller (pomaceous fruitwood) 0.03 3 0.94 3 Prunus avium/padus L. (wild/bird cherry) 0.82 17 0.38 12 Quercus spp L. Liebl (oak) 0.94 6 0.01 1 Salix spp L. (willow) 0.08 1 * w = weight in grams; f = fragment count.

Sample 1 2 2 7 7 Feature 21 55 55 40 40 Context w f w f w f Alnus glutinosa L. Gärtner (alder) 0.03 2 0.02 1 Corylus avellana L. (hazel) 0.01 1 Fraxinus excelsior L. (ash) 0.05 3 Pomoideae L./Miller (pomaceous fruitwood) 0.12 2 Quercus spp L. Liebl (oak) 0.21 10 0.2 11 Salix spp L. (willow) 0.37 20 * w = weight in grams; f = fragment count.

122


32 32

22 22

91 91

61 61

51 51

41 41

31 31

01 01

9 9

elpmaS

1 1

57 57

86 86

16 16

16 16

45 45

45 45

04 04

04 04

erutaeF 1

1 1

1 2

2 1

1 2

2 E1

E1 txetnoC

w

f

w

f w

f

w

f w

f

w

f w

f

w

f w

f

Alnu

s glu

tinos

a L.

Gär

tner

(ald

er)

0.02

1

2.34

36

0.

11

3

0.

21

10

0.1

2 0.

06

1 Co

rylu

s ave

llana

L. (

haze

l) 0.

08

3

0.

96

32

0.08

2

Frax

inus

exc

elsio

r L. (

ash)

0.

02

1

0.

02

1 0.

07

1

Po

moi

deae

L./M

iller (

pom

aceo

us fr

uitw

ood)

Pr

unus

aviu

m/p

adus

L. (

wild

/bird

che

rry)

0.

41

18

Prun

us sp

inosa

L. (

blac

ktho

rn)

0.05

1

Quer

cus s

pp L

. Lie

bl (o

ak)

1.59

10

0 1.

39

51

0.07

1

1.74

50

0.

06

3 0.

71

43

2.93

10

0 1.

57

45

Salix

spp

L. (

willo

w)

0.01

1

Ilex

aqui

foliu

m L

. (ho

lly)

0.04

1

w

= w

eigh

t in

gram

s; f

= fr

agm

ent

coun

t.


123

Tabl

e 8.

4—C

harc

oal i

dent

ifica

tion

deta

ils f

rom

site

D (

05E0

949)

.

Tabl

e 8.

5—C

harc

oal i

dent

ifica

tion

deta

ils f

rom

the

cas

tle d

itch

site

(05

E041

4 ex

t.).

87

87

16

16

94

94

54

54

93

93

63

63

13

13

03

03

12

12

61

61

51

51

41

41

7

7

5

5 elp

maS 5

51

551

94

94

3

01

301

67

67

85

85

94

94

13

13

13

13

7

7

81

81

31

31

11

11

1

1

1

1

erutaeF

6

6

6

6 txetn

oC

2

2

19

19

7

7

4

4

65

65

f

w f

w

f

w f

w

f

w f

w

f

w f

w

f

w f

w

f

w f

w

f

w f

w

Alnu

s glu

tinos

a L.

Gär

tner

(ald

er)

2.99

29

0.

1 4

Cory

lus a

vella

na L

. (ha

zel)

0.

18

7 3.

9 22

0.

06

1 0.

08

1 0.

33

1

0.

05

1

0.

15

3 0.

08

6

Fr

axin

us e

xcel

sior L

. (as

h)

0.16

4

0.1

1 0.

08

1

23

.07

1 99

11

0

7.

77

1 0.

1 2

0.81

10

0.

23

6 3.

7 29

Po

moi

deae

L./M

iller (

pom

aceo

us fr

uitw

ood)

0.

08

3

Pr

unus

aviu

m/p

adus

L. (

wild

/bird

che

rry)

0.

07

1

0.

1 1

0.32

7

0.05

1

0.1

1 Qu

ercu

s spp

L. L

iebl

(oak

)

0.

05

1 0.

03

1 8.

28

62

1.8

26

Salix

spp

L. (

willo

w)

0.4

12

0.05

1

Ilex

aqui

foliu

m L

. (ho

lly)

0.03

1

Ulm

us g

labr

a L.

(el

m)

0.

1 2

0.03

1

* w

= w

eigh

t in

gram

s; f

= fr

agm

ent

coun

t.



Documents

Charcoal analysis, Killeen Castle, Co. Meath