Because of the Coronavirus pandemic I have not managed to conduct any of my fieldwork abroad during spring/summer 2020. However, since I have been back in the office and the labs I have managed to get involved on a couple of UK based projects. These UK projects were lucky enough to get the go ahead with social distancing measures in place.
I wanted to share some information about both of these fantastic projects. The first is a Bournemouth University excavation run by Prof Tim Darvill near to Cirencester. The second is a project run by a colleague who is also a phytolith expert, Dr Emma Karoune, in collaboration with Historic England.
Sisters Long Barrow:
Sisters long barrow is a 6000 year old prehistoric burial mound located close to Cirencester (https://www.bournemouth.ac.uk/news/2016-09-26/bu-archaeologists-uncover-6000-year-old-long-barrow-cotswolds). One of these Neolithic long barrows has not been excavated since the 1970’s. This year’s excavations removed all of the stone collapse around the burial mound to reveal the prehistoric ground surface on which the burial mound was constructed. This surface was being analysed every 50cm on site using a portable x-ray fluorescence analyser (the same device I use in my research) to analyse a range of geochemical elements. While this analysis can be conducted very quickly, in situ, in a non-destructive way, we were there to take small sediment samples for further laboratory analyses. We took small soil samples from the surface every 50cm around the mound. While this totalled a LOT of samples (c.160!), this would give us the opportunity at a later date to target which samples to process for phytolith analysis based on the geochemical results. Also, it is advantageous to sample archaeological deposits when they are first revealed to prevent any contamination. These samples can be stored for a long time, creating an archive, and potentially be used for other analyses at a later date. In addition these sediment samples will be analysed by magnetic susceptibility, which is also relatively quick and non-destructive method to determining areas of burning. Combining the geochemical, magnetic susceptibility and phytolith results will enable a thorough analysis of the prehistoric ground surface and enable different areas of activities to be detected. If the pXRF results show elevations or depletions in elements, then these locations can be targeted for phytolith analysis to determine whether we see any changes in the signatures from the plants in the same locations.
Farlington Marshes Modern Plant Reference Material for UK based phytolith reference collection:
Dr Emma Karoune is currently conducting a project in association with Historic England and is supported with funding by the Association for Environmental Archaeology (AEA), and the Botanical Society of Britain and Ireland. Emma received an AEA small grant and Botanical Society for Britain and Ireland small research grant to begin this project. The fieldwork which I helped with is a part of a larger project to establish a comprehensive phytolith reference collection for plant communities in Southern Britain that can be used to develop a new methodology for investigating past plant exploitation on British Archaeological sites. Plant material is being collected from around the Portsmouth area such as at Farlington Marshes and Eastney beaches, which has salt marsh, grazing marsh and coastal dune habitats. During this project, some of the plant material will be made into a herbarium collection to be housed at Portsmouth Museum. In subsequent work, the rest of the plant material will then be ashed and mounted onto slides (a free collection of phytolith slides to be housed at Fort Cumberland, Historic England) to identify and classify the different phytolith morphotypes found in each plant species.
I spent a day with Emma and one of BU’s undergraduate students Siggy Osborne at Farlington Marshes, close to Portsmouth. Permission for plant collecting has been given by Hampshire & Isle of Wight Wildlife Trust and Portsmouth County Council (thanks to Chris Lycett for coordinating access). During the day I spent with Emma and Siggy we were selecting areas to collect the different plant species. In addition soil samples from each plant community have also been collected and will be analysed (with help from the plant reference slides) to categorise modern analogues for each plant community that can be used to address questions of landscape change around archaeological sites. The combination of the examination of phytoliths from plant material and soil samples within British plant communities is a new technique that Emma is developing to produce a robust methodology for the application of phytolith analysis to archaeological assemblages.
Emma will be creating an on-line open access phytolith database, which is desperately needed for the UK. It was great to spend the day plant collecting. The marsh area was beautiful; it is a nature reserve and is a Site of Special Scientific Interest (SSSI). Lots of bird watchers were these observing the birds who live within the marshes. We were even lucky to see the starling murmurations!
Thanks to BU, Prof Tim Darvill, Dr Emma Karoune and Sigrid Osborne.
Photo credits to Harry Manley and Sigrid Osborne.
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