FARWAY CASTLE, EAST DEVON: POLLEN ASSESSMENT REPORT

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1 Quaternary Scientific (QUEST) Unpublished Report April 0; Project Number 07/ FARWAY CASTLE, EAST DEVON: POLLEN ASSESSMENT REPORT C.R. Batchelor Quaternary Scientific (QUEST), School of Human and Environmental Sciences, University of Reading, Whiteknights, PO Box 7, Reading, RG AB, UK INTRODUCTION This report summarises the findings arising out of the pollen assessment undertaken by Quaternary Scientific (QUEST), University of Reading in connection with archaeological investigations carried out at Farway Castle, East Devon by ARCA, University of Winchester. Sub-samples were taken for pollen assessment from a borehole that was put through a Medieval ditch. The aim of the assessment was to evaluate the potential of the sedimentary sequence for reconstructing the vegetation history of the site and its environs. METHODS Pollen assessment Eight sub-samples were extracted for the assessment of pollen content, and was extracted as follows: () sampling a standard volume of sediment (ml); () adding two tablets of the exotic clubmoss Lycopodium clavatum to provide a measure of pollen concentration in each sample; () deflocculation of the sample in % Sodium pyrophosphate; () sieving of the sample to remove coarse mineral and organic fractions (>5μ); (5) acetolysis; () removal of finer minerogenic fraction using Sodium polytungstate (specific gravity of.0g/cm ); (7) mounting of the sample in glycerol jelly. Each stage of the procedure was preceded and followed by thorough sample cleaning in filtered distilled water. Quality control is maintained by periodic checking of residues, and assembling sample batches from various depths to test for systematic laboratory effects. Pollen grains and spores were identified using the University of Reading pollen type collection and the following sources of keys and photographs: Moore et al (99); Reille (99). Plant nomenclature follows the Flora Europaea as summarised in Stace (005). The assessment procedure consisted of scanning the prepared slides, and recording the concentration and preservation of pollen grains and spores, and the principle taxa on four transects (0% of the slide) (Table ). The addition and counting of Lycopodium spores has also permitted the calculation of total land pollen grains/cm.

2 Quaternary Scientific (QUEST) Unpublished Report April 0; Project Number 07/ RESULTS, INTERPRETATION AND DISCUSSION OF THE POLLEN ASSESSMENT The results of the pollen assessment indicate that pollen preservation and concentration was excellent in all samples, and that microscopic charred particles were present in samples 9-0 to 9-0. In all samples except 9-0, tree and shrub taxa dominated, with limited herbs and spores and no aquatics. () and () dominated, with Pinus (), () and () recorded in most samples. Calluna vulgaris was dominant in sample 9-0. (), Fraxinus (ash), (), Rosaceae (rose family), Ulmus (elm) and Tilia (lime) were recorded in low concentrations in certain samples. Herb taxa included () and Plantago species (plantain), whilst spore taxa comprised () and Polypodium vulgare (polypody). Lowermost sample 9-0 was dominated by and with a few grains of Pinus,,, (), Dryopteris type and Polypodium vulgare. The ditch investigated represents a small depositional basin, and thus will have a correspondingly small pollen sources area, reflecting predominantly the vegetation of the immediate locality of the site. The results of the assessment indicate an initial open local environment dominated by grass and followed by the growth of predominantly and dominated woodland with limited occurrences of other mixed deciduous and coniferous trees such as, hazel,, elm and lime. Heather was also a reasonably commonly growing plant during the central fill of the ditch. No unequivocal evidence for human activity (such as cereal pollen) was recorded during the course of the assessment. However, it is of note that the provisional vegetation history of the site was a local environment dominated by taxa indicative of an open environment, potentially modified by human activity at the base of the sequence, followed by an environment dominated by and. It is unclear at this stage what the cause of this transition was, but three possibilities are suggested here: () the function of the ditch may have become related in some way to the use of these specific woodland taxa; () and were planted near or on the site (e.g. hedgerow), or () the basal sample represents the environment of the site during its occupation, whilst those above it represent the growth of woodland after abandonment. It is considered that scenario () or () are the most plausible.

3 Quaternary Scientific (QUEST) Unpublished Report April 0; Project Number 07/ RECOMMENDATIONS The preservation and concentration of pollen is excellent, and a full count (analysis) is very achievable. Such analysis would confirm the change in pollen assemblage towards the base of the sequence as well as provide further evidence for the potential causes. Furthermore, such analysis would elucidate evidence for specific human activity taking place at the site such as cultivation and crop processing. REFERENCES Moore, P.D., Webb, J.A. and Collinson, M.E. (99) Pollen Analysis ( nd Blackwell. Ed.). Oxford: Reille, M. (99) Pollen et Spores d Europe et d Afrique du Nord. Marseille : Laboratoire de Botanique Historique et Palynologie. Stace, C. (005) New Flora of the British Isles. Cambridge: Cambridge University Press.

4 Quaternary Scientific (QUEST) Unpublished Report December 0; Project Number 00/ Table : Pollen-stratigraphic assessment of samples from Farway Castle, East Devon Sample number Main pollen taxa Latin name Common name Number Concentration 0-5 Concentration grains/cm - Pinus Fraxinus Ranunculus type Diatom 5- Pinus 9-0 Pinus Plantago media/major Polypodium vulgare - Rosaceae Cyperaceae Asteraceae 7- Pinus ash buttercup hoary/common plantain polypody fern rose family sedge family daisy family Preservation Microcharcoal 0-5

5 Quaternary Scientific (QUEST) Unpublished Report December 0; Project Number 00/ Ulmus Rumex obtusifolius elm broad-leaved dock lime polypody fern cinqufoil Tilia 9 7 Polypodium vulgare 5- Pinus Potentilla type 9-0 Pinus Polypodium vulgare polypody fern Key: Concentration: 0 = 0 grains; =-75 grains, = 7-50 grains, = 5-5 grains, = -00, 5 = 00+ grains per slide Preservation: 0 = none, = very poor, = poor, = moderate, = good, 5 = excellent Charcoal: 0 = none, = negligible, = occasional, = moderate, = frequent, 5 = abundant 5

The micropalaeontology and palynology of a putative lacustrine clay deposit at Spittalmyre Farm, Montrose [1:50k sheet 57 (E) Montrose]

The micropalaeontology and palynology of a putative lacustrine clay deposit at Spittalmyre Farm, Montrose [1:50k sheet 57 (E) Montrose] Geology and Landscape Northern Britain Programme Internal Report