ÅHM 5354, Postgården (4296/71)

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1 ÅHM 5354, Postgården (4296/71) Kort & Matrikelstyrelsen (G ) Analysis of carbonized plant remains from an Early Germanic Iron Age (Ældre germansk jernalder) cremation burial Santeri Vanhanen, BA KONSERVERINGS- OG NATURVIDENSKABELIG AFDELING Nr

2 ÅHM 5354, Postgården (4296/71) Analysis of carbonized plant remains from an Early Germanic Iron Age (Ældre germansk jernalder) cremation burial Santeri Vanhanen, BA Introduction The archaeological excavations conducted by the Aalborg Historiske Museum at Postgården revealed a burial ground dating to the Late Roman Iron Age/Early Germanic Iron Age (YRJ/ÆGJ)(fig.1) and other structures dating to the Bronze Age and Late Iron Age 1. The burial ground consisted of both cremation and inhumation burials and the studied archaeobotanical samples derive from the cremation burials. Sample processing Sixteen samples were flotated by Åge Brandi with Moesgård Museums flotation machine. The machine consists of a wide and sloping metal sink, where a stream of water runs from its lower end. The beforehand dried soil samples are poured into the sink in portions with a volume up to 5 litres. Floating material is then released by the water stream. This separates the light fraction (mostly organic material) and heavy fraction (mostly inorganic material) from each other. The light fraction often includes charred plant remains. The stream of water takes the light fraction into a 0,25 mm cloth sieve. The light fraction is then dried, and it is thereby ready for an archaeobotanical analysis. The non-floating heavy fraction is also spared and it is examined for archaeological finds: bones, ceramics, flint etc., which do not float. Both the heavy and the light fraction are then sent to the Moesgård Museets Konservering- og Naturvidenskabelige Afdeling (Moesgaard Museums Department for Environmental Archaeology and Conservation) for further treatment. 1 The site number is SB 47. The location of the excavation was situated in Sønder Tranders sogn (parish), Fleskum herred (shire), Ålborg amt (county). Map: 4cm kort: 1316 IV NV UTM: / Zone: 32 1

3 The cursory analysis These samples were then cursorily analysed by mag.art. Marianne Høyem Andreasen. This was done with a microscope using up to X40 magnification. During the cursory analysis all 16 samples were examined to gain an approximate evaluation of the sample content. The cursory analysis revealed that some of the samples contained charred archaeobotanical material in the form of cereal grains, seeds and Calluna vulgaris (hedelyng) stems (see app. 1). Based on the large number of archaeobotanical material, sample no. X231 was chosen for a thorough archaeobotanical analysis. The context of the analysed sample The sample is taken from a cremation grave (A 318) (fig. 2). The grave had an oval filling, measuring ca. 2,3 x 0,9 m with a NW-SE orientation. The depth of the grave was ca. 43 cm and the cross-section was bathtub-shaped with flat bottom and slightly sloping walls. The grave contained a burnt layer, which comprised of wood remains and bones still in their correct anatomical positions. The position of the bones suggests that the corpse has been burned in the grave. There were ceramic shards and flint pieces found in situ. The grave has been interpreted as a hybrid grave, where the corpse has been burned in the place and then covered with soil. The interpretation is backed by the findings of bones in their correct anatomical positions and the wood that could have been used for fuel to burn the corpse. Fig. 1. The graves and the studied samples. The results are based on the cursory analysis 2

4 The results of the archaeobotanical analysis The archaeobotanical analysis revealed a great deal of cultivated plants, weeds and other plants. Most of the plants are connected with agricultural activities, but there were also stems of Calluna vulgaris (hedelyng). Cultivated cereals consisted mostly of Hordeum vulgare (byg) and Avena sp. (havre), but also one Secale cereale (rug) grain was found. Most of the Hordeum grains identified to the variety level were Hordeum vulgare var. vulgare (avnklædt byg), but also some Hordeum vulgare var. nudum (nøgen byg) grains were present. Avena grains were most probably cultivated Avena sativa (dyrket havre) as some grains with glumes attached and also loose floret bases were found, which resembled Avena sativa. In addition to these there were also quite many Linum usitatissimum (almindelig hør) seeds. The weed flora was clearly dominated by two species: Spergula arvensis (almindelig spergel) and Persicaria maculosa/lapathifolium (bleg-/fersken pileurt). In addition Chenopodium sp. (gåsefod), Fallopia convolvulus (snerlepileurt), Galeopsis sp. (hanekro), Plantago lanceolata (lancetvejbred), Rumex acetosella (rødknæ), Scleranthus annuus (enårig knavel), cf. Urtica dioica (cf. stor nælde) and Vicia sp. (vikke) seeds were found, but these were present in X-NR: 231 X-NR Original sample volume (l.) 12 Oprindelig jordprove (l.) Flotated volume (ml.) 220 Floteringprøve (ml.) Avena sp. 116 Havre sp. Avena cf. sativa grain and glume 2 cf. Dyrket havrekorn med avn Avena cf. sativa floret base 5 cf. Dyrket havre (avnbase) Cerealia indet. 471 Korn ubestemmelig Hordeum vulgare var. vulgare 196 Avnklædt byg Hordeum vulgare cf. var. nudum 18 cf. Nøgen byg Hordeum vulgare 134 Byg sp. Linum usitatissimum 43 Almindelig hør Secale cereale 1 Rug Cyperaceae 191 Halvgræsfamilien Chenopodium sp. 5 Gåsefod sp. Fallopia convolvulus 1 Snerlepileurt Galeopsis sp. 1 Hanekro Persicaria maculosa/lapathifolium 334 Bleg-/Fersken-pileurt Plantago lanceolata 1 Lancetvejbred Poaceae 2+1(4) Græsfamilien Rumex acetosella 5 Rødknæ Scleranthus annuus 1 Enårig knavel Spergula arvensis (128) Almindelig spergel cf. Urtica dioica 1 cf. Stor nælde Vicia sp. 1 Vikke Indet. ca. 20 Ubestemmelige Carbonized twigs present Forkullede strå Calluna vulgaris stems present Hedelyngstængler Burned bones present Brændt knogle Flint present Flint Charcoal (X-XXXXX) XXXXX Trækul (X-XXXXX) Table 1. The results of the archaeobotanical analysis of the sample X231 3

5 Fig 2. The grave A318 much smaller quantities than the two first mentioned species. The abovementioned Persicaria spp. thrive on moist fields (Brøndegaard 1979:132). Spergula arvensis thrives on often sandy, acid and nutrient poor soil and it grows often as a field weed (Hansen 1993:150) especially in Hordeum fields. Also quite many Cyperaceae (halvgræsfamilien) nutlets were found. Discussion It is interesting that so many cultivated plants, weeds and wetland plants were found in this grave. The most interesting question here is the origin of 4

6 these different plants in the grave. As the corpse has been burned in situ, the plant remains must derive from the time between the digging of the grave and its covering. There are at least two possible interpretations: 1) The plant material has been a part the pyre together with firewood 2) The plant material has been put on the pyre at the same time as the corpse was being burned or after that. It is quite difficult to be certain in this issue but there are some facts that support these explanations. The essence of the plant material is one clue. As it consists mostly of plants used for food (cereals, Linum and some weeds) and these do not contain straws, Linum capsules etc., it most probably represents cereal grains and Linum seeds that are ready for use as food. However some of the plants, Calluna vulgaris, Cyperaceae and some of the weeds have most probably not been consumed during the prehistoric times, so these could represent material used for the burning of the pyre. Most species in Cyperaceae family thrive in wetlands and many of them have been used as a fodder in the prehistoric and historic times. Also Plantago lanceolata can be an indication of fodder, but it may also grow as a field weed. But in this case it seems to be more reasonable that these plants do not represent fodder as the context is not related with husbandry activities. Dry Cyperaceae straws could have been well suited to kindle the pyre, as probably also dry Calluna stems, which were found from other graves on the location (fig. 1). Though the cereals and Linum are cultivated and most probably consumed, the consumption of the Spergula arvensis and Persicaria spp. is not that self-evident. But on the other hand fruits and seeds of these plants have been found often both collected and in the gut contents of bog bodies (Behre 2008:68). New quantitative analysis of the gut contents of Grauballe man has revealed that Persicaria lapathifolium, Persicaria maculosa and Spergula arvensis have been the most abundant plant species consumed by him (Harild 2007:172). So it could be possible that these have been collected and then sacrificed for the deceased together with other food plants. The time when all the found plants have been flowering is July-August, so if it is supposed that these plants have been collected during the same year and not preserved, the introduction of the plants to the burial could not have taken place before July. The weed flora does not contain taxa related to winter crops and it is most plausible that only summer crops have been cultivated. The assemble indicates cultivation of Hordeum vulgare var. vulgare and most probably also Avena sativa and Hordeum vulgare var. nudum. As only one single Secale cereale grain is present, it is possible that this plant has not been put into the grave intentionally. This does not mean that it was not cultivated, but it has been introduced into the assembly unintentionally. Hordeum vulgare var. vulgare is common for the Late Iron Age. The amount of Hordeum vulgare var. nudum declines in the course of the Iron Age (Hardt 2003:42) and this can be seen also from this assemblage as small proportion of it is still found. It is also quite typical that Avena sp. is cultivated during this period. The assembly seems to represent intentional usage of food plants during the Late Iron Age. The question of intentional addition of weed seeds into the graves should be studied further. It could also be interesting to study the usage of Calluna vulgaris and Cyperaceae as a part of the fuel in the pyre. The composition wood species and the size of the wood used could also be interesting to get more knowledge on the construction of a pyre. 5

7 Literature: Behre, K.A. 2007: Collected seeds and fruits of herbs as prehistoric food. Vegetation history and archaeobota 17. Bøndegaard, V. J. 1979: Folk og flora. Dansk etnobotanik. 2. Rosenkilde og Bagger. Hardt, Nis 2003: Jernalderens og vikingetidens landbrug, s I: Per Ethelberg, Nis Hardt & Anne Birgitte Sørensen: Det Sønderjyske Landbrugs Historie Jernalder, Vikingetid og Middelalder. Haderslev Museum 2003 Harild, Jan Andreas, David Earle Robinson & Jesper Hudlebusch 2007: New analyses of Grauballe Man s Gut Contents, s I: Pauline Asingh & Niels Lynnerup (red.): Grauballe Man. An Iron Age Bog Body Revisited. Aarhus University Press 6

8 Planterne de dyrkede arter Avena sativa L. Almindelig Havre cm høj. Optræder ofte sammen med Flyvehavre. (Hansen 1993) Hordeum vulgare L. Seksradet byg (nøgen + avnklædt) cm høj. Højden kan have ændret sig på grund af avling. (Mossberg & Stenberg 2005) Linum usitatissimum L. Almindelig Hør. Højde cm. (Hansen 1993) Secale cereale L. Almindelig Rug. Højde cm. Højden har ændret sig på grund af avling, se f.eks. Tvengsberg (Hansen 1993) Identificerede planter Calluna vulgaris (L.) Hull. Hedelyng cm, blomstrer august-september. Flerårig. Heder, klitheder, hedemoser, tørre dele af højmoser. (Hansen 1993) Fallopia convolvulus L. Snerle Pileurt cm lange stængler, som enten er nedliggende eller slynger sig op om stængler, strå og blade fra andre planter, omkring frø pr. plante. Blomstrer og frømodning juli-september. Udpræget sommerannuel, modnes sammen med korn og hør. Knyttet til kornmarkerne og forekommer almindeligt i vårsæd hvor den er mest generende samt i Hør, kan fremme lejesæd i kornet. Agerjord, ved bebyggelse. (Melander 1998, Frederiksen et al. 1950) Plantago lanceolata L. Lancetbladet Vejbred cm (10-30 cm) langt blomsterskaft, omkring frø pr. plante, dog på en stor plante. Blomstrer maj-juni, frømodning august-oktober. Flerårig. Overdrev, skrænter, marker, vedvarende græsmarker og ruderater. (Frederiksen et al. 1950, Hansen 1993) Rumex acetosella L. Rødknæ cm høj, omkring frø pr. plante. Flerårig. Udpræget vegetativ formering. Optræder som ukrudt i alle afgrøder på magre kalkfattige sandjorder og tørre humusagtige jorder. Grå klit, strandoverdrev, sandede overdrev og vedvarende græsmarker, vejkanter, skovrydninger, agerjord. (Frederiksen et al. 1950, Hansen 1993, Jessen & Lind 1922) Scleranthus annuus L. Enårig Knavel cm stængler. Blomstrer næsten hele året, dog fortrinsvis maj-juni. Er enten sommerannuel eller overvintrende enårig. Forekommer almindeligt som ukrudt i både vårsæd og vintersæd i let, kalkfattig jord. Særlig hyppig i rug, og regnes som en af de mest sikre karakterplanter for kalktrængende jorder. Sandet, især næringsfattig, tør agerjord. (Frederiksen et al. 1950, Hansen 1993) Spergula arvensis L. Alm. Spergel cm (10-30 cm) høj, omkring frø pr. plante. Blomstrer og frømodner juni-september. Frøene spirer både forår og efterår, men de efterårsspirende fryser som regel bort om vinteren og kan kun overleve meget milde vintre. Kan optræde uhyre talrigt i vårsædsmarker, især på lette kalktrængende jorder. Værdsat i stubmark som foder til fårene. Agerjord, især næringsfattig bund. (Frederiksen et al. 1950, Hansen 1993, Jessen & Lind 1922) 7

9 Svært adskillelige planter Persicaria maculosa L. Ferskenbladet Pileurt cm høj, omkring frø pr. plante. Blomstrer og frømodner juli-september. Rent sommerannuel (kan også forekomme i vintersæd, Melander 1998). Forholder sig som Persicaria lapathifolium. Agerjord, ofte vandlidende, ruderater. (Frederiksen et al. 1950, Hansen 1993, Jessen & Lind 1922) og Persicaria lapathifolium L. Blegbladet Pileurt cm (25-80 cm) høj, omkring frø pr. plante. Blomstrer og modner frø i juli-september. Udpræget sommerannuel plante. Kan være meget skadelig i vårsæden, især i lave noget vandlidende marker, hvor den kan forekomme meget talrigt, kan også forekomme i vintersæden. (Melander 1998, Frederiksen et al. 1950, Hansen 1993) Usikker bestemmelse Urtica dioica L. Stor Nælde cm høj. Omkring frø pr. plante. Blomstrer juli-august. Skadelig i varige græsmarker på muldrig eller moseagtig jord. Askeskove, hegn, vejkanter, ruderater. (Frederiksen et al. 1950, Hansen 1993) Persicaria maculosa/lapathifolium cf. Bleg-/Fersken-pileurt cf. (Se under Svært adskillelige planter ovenfor. Planter identificeret til slægt eller familie Avena sp. Havre sp. Cyperaceae Halvgræsfamilien Cerealia indet. Korn ubestemmelig. Chenopodium sp. Gåsefod sp. Galeopsis sp. Hanekro sp. Galium sp. Snerre sp. Poaceae sp. Græsser sp. Vicia sp. Vikke sp. Litteraturliste Frederiksen, H. & P. Grøntved, H.I. Petersen 1950: Ukrudt og ukrudtsbekæmpelse. Det Kongelige Danske Landhusholdningsselskab. København Hansen, K. 1993: Dansk feltflora. 1. udgave, 6. oplag. København. Jessen, K. & J. Lind 1922: Det Danske Markukrudts Historie. Det Kongelige Danske Videnskabernes Selskabs Skrifter, naturvidensk. og mathem. Afd., 8 Række, VIII. København. Melander, B. 1998: Beskrivelse af ukrudtsplanterne. I: Ukrudtsbekæmpelse i landbruget. Forskningscenter Flakkebjerg. Afdeling for Plantebeskyttelse. 3. udgave. pp Tvengsberg, P.M. 1995: Rye and swidden cultivation tillage without tools. Tools & Tillage. Vol. VII: 4. s

10 Appendix 1. The results of the cursory analysis. EGNET TIL X-NR ANALYSE? Korn Frø Trækul Øvrige bemærkninger 218 Nej 0 0 x 224 Nej 0 0 xx Lyngstængler 225 Nej 0 <10 xxxx Flere store stykker trækul. Lyngstængler 226 Nej 0 0 xx 1 stort stykker trækul. Lyngstængler 227 Nej 0 0 xx Mange lyngstængler 228 Nej 0 <10 xxx Flere store stykker trækul. Brændt knogle. Lyngstængler 230 Nej 0 0 xxx Få store stykker trækul 231 Ja Mange Mange xxx Brændt knogle. Avnklædt byg, havre, hør, spergel, pileurt. Lyngstængler 232 Nej 0 0 xxx Få store stykker trækul 233 Nej xxxx Flere store stykker trækul. Brændt knogle. Lyngstængler med rod 234 Nej 0 0 xxxx Trækulsfnuller. Lyngstængler. Få kornfragmenter 235 Nej 0 Oct-30 xxxx Flere store stykker trækul. Slagge af organisk materiale. Lyngstængler 236 Nej xxxx Flere store stykker trækul. Få kornfragmenter 237 Nej 0 0 xxxx Flere store stykker trækul. Trækulsfnuller 240 Nej <5 <5 xx Få store stykker trækul. Byg 249 Nej <10 <5 xxxx Flere store stykker trækul 9

11 Rapporterne fra Moesgårds Naturvidenskabelige Afdeling fremlægger resultater i forbindelse med specialundersøgelser af arkæologisk genstandsmateriale. Hovedvægten er lagt på undersøgelser med en naturvidenskabelig tilgangsvinkel. Heriblandt kan nævnes arkæobotaniske undersøgelser, vedanatomiske undersøgelser, antropologiske undersøgelser af skeletter samt arkæozoologiske undersøgelser. Der optræder også andre typer dokumentationsfremlæggelser, som f.eks. besigtigelse af marinarkæologiske lokaliteter og metodebeskrivelser af konserveringsteknisk karakter. Alle rapporterne kan downloades fra Moesgård Museums hjemmeside Eftertryk med kildeangivelse tilladt. 10