Appendix Jii The Impact of Potato Growing on Archaeological Sites. Paul White ©Herefordshire Council, 2001 Oxford Archaeology May 2002 (revised December 2002) Herefordshire Archaeology is Herefordshire Council’s county archaeology service. It advises upon the conservation of archaeological and historic landscapes, maintains the county Sites and Monument Record, and carries out conservation and investigative field projects. The County Archaeologist is Dr. Keith Ray. The Impact of Potato Growing on Archaeological Sites. A Preliminary Study Herefordshire Archaeology Report No. 44 Report prepared by Paul White Herefordshire Archaeology Conservation and Environmental Planning Planning Services Environment Directorate Herefordshire Council Copyright Herefordshire Council. 2001 Contents Page List of figures i Summary ii 1. Introduction 1 2. Impact of arable farming upon archaeological sites 2 3. Potato cultivation in Herefordshire: A national, regional and county perspective 3 4. Possible/ projected impacts of potato cultivation in Herefordshire 6 5. Study procedures 8 5.1 Defining archaeological sites 8 5.2 Fieldwork procedures 8 5.3Analytical procedures 9 6.The field investigations 11 6.1 SITE 1: Downfield Knoll, Sutton St. Michael 11 6.1.1 Site location and Definition 11 6.1.2 Recent Agricultural History 12 6.1.3 Archaeological Investigations and findings 12 6.2 SITE 2: Ridgeway, Cradley 16 6.2.1 Site location and Definition 16 6.2.2 Recent Agricultural History 16 6.2.3 Archaeological Investigations and findings 17 6.3 SITE 3: Liglok Field, Westhide 24 6.3.1 Site location and Definition 24 6.3.2 Recent Agricultural History 24 6.3.3 Archaeological Investigations and findings 26 7. Analysis 31 7.1 Sutton 31 7.1.1 Site Interpretation 31 7.1.2 Assessment of arable impacts 31 7.1.3 Summary 32 7.2 Cradley 33 7.2.1 Site Interpretation 33 7.2.2 Assessment of arable impacts 33 7.2.3 Summary 35 7.3 Westhide 36 7.3.1 Site Interpretation 36 7.3.2 Assessment of arable impacts 37 7.3.3 Summary 38 8. Assessment of the impact of potato cultivation on archaeological sites 39 8.1 Implications of potato cultivation in Herefordshire 39 8.2 Recommendations 41 References 43 Acknowledgements 44 List of Figures Page 1. The geographical expansion of potato production in Herefordshire, 1988- 1999, based on MAFF agricultural parish groups 3 2. Distribution of potatoes, based upon 1999 June Agricultural Census 5 3. West Midlands Regional Counties Holdings to Potato Hectares ratio 6 4. Location of archaeological sites investigated in Herefordshire 10 5. Cropmark enclosure at Downfield Knoll, Sutton St. Michael 11 6. Location of cropmark, excavated area, geophysics survey and limit of contour survey at Downfield Knoll 12 7. 30 metre square geophysics survey and interpretation at Downfield Knoll 13 8. Excavation plan at Downfield Knoll 14 9. Aerial photograph of Ridgeway, Cradley 16 10. Location of cropmark, excavation trenches, geophysics and contour survey at Ridgeway, Cradley 17 11. Excavation plan and section of RC00 Trench 1 18 12. West facing section drawing of RC2/00 Trench 1 19 13. Excavation plan of RC2/00 Trench 1 and 2 20 14. Section drawing of the enclosure ditch in RC2/00 Trench 2 21 15.Results of resistivity survey at Ridgeway, Cradley 22 16. Fieldwalking results at Westhide 24 17. Location of excavation trenches, geophysics survey, projected line of sewer and limit of the contour survey at Westhide 24 18. Photo of furnace in WH01 trench 1 25 19. Pre- post excavation plan WH01 trench 1 26 20. Westhide Section Drawing 28 21. Results of the resistivity survey at Westhide 29 22. Downfield Knoll. Survival of cropmark mapped against contour survey 31 23.Results of resistivity survey and interpretation at Ridgeway, Cradley 33 24. Westhide Artefact distribution compared to contour survey 36 25. The impact of deepening the plough zone by potato cultivation 39 26. Impact of conventional ploughing upon archaeology 39 TABLE 1. Profile of England’s potato production, based on 2000 Agricultural census 5 i The Impact of Potato Growing on Archaeological Sites. A Preliminary Study Herefordshire Archaeology Report No 44, November 2001. Summary: During October and November 2001, Herefordshire Archaeology undertook a preliminary study of the impact of the potato cultivation on archaeological sites within the county. The purpose of the study was to inform a national study on the management of archaeological sites within arable landscapes currently being undertaken by the Oxford Archaeological Unit on behalf of the Department of Environment, Food and Rural Affairs. The extent of potato farming within the county is revealed and the future impacts of potato cultivation in Herefordshire are also considered. Three sites were investigated at Sutton St. Michael, Cradley and Westhide form the basis of this report. The sites at Sutton and Cradley are defined as cropmark enclosures while Westhide is a small Romano- British settlement. All of the sites revealed damage from agricultural processes, with evidence of accelerated erosion of the buried archaeological deposits due to potato growing at Sutton and Cradley. The sites confirmed that various factors, such as slope, topographic location and crop regime would influence the occurrence of damage from arable farming on archaeological remains. The study concludes with an assessment of the impact of potato cultivation on archaeological sites with recommendations highlighting a series of various options that may be undertaken to manage archaeological sites in arable landscapes in the future. Disclaimer: It should not be assumed that land referred to in this document is accessible to the public. Location plans are indicative only. NGR’s are accurate to approximately 10m. Measured dimensions are accurate to within 1m at a scale of 1:500, 0.1m at 1:50, and 0.02m at 1:20. This study contains material from the Ordnance Survey. The grid in this material is the National Grid taken from the Ordnance Survey map with the permission of the Controller of Her Majesty’s Stationery Office. This material has been reproduced in order to locate the site in its environs. Contact details: Herefordshire Archaeology, PO Box 144, Hereford, HR1 2YH. 1. Introduction This report provides an account and analysis of work carried out by Herefordshire Archaeology in 2001. It aim has been to contribute to a wider project undertaken by the Oxford Archaeological Unit, on behalf of DEFRA (Department of Environment, Food and Rural Affairs) on the management of archaeological sites in the arable landscape. The primary concern of the national study is to consider specific cultivation processes that occur in the arable landscape to assess the impact on archaeological sites. The main purpose of the project reported here was to provide a preliminary assessment of the kinds of impact of arable cultivation upon the buried archaeological resource within Herefordshire. Special reference was made to potato cultivation that has become a major agent of change in the farmed landscape of the county. The Herefordshire study involved re- examining previous Herefordshire Archaeology excavations and undertaking new fieldwork so that site damage linked to agricultural processes could be assessed. The report is divided into eight main sections. · Section 1, this introduction. · Section 2, providing a brief overview and assessment of the current impact of arable farming upon the archaeological resource. · Section 3, reviewing potato cultivation in Herefordshire set against a national and regional context. · Section 4, specifying the implications of increased potato cultivation and changes to cultivation methods. · Section 5: A statement of the study procedures. · Section 6 detailing the fieldwork and investigations findings. · Section 7, analysing these findings. · The study is concluded with an assessment of the impact of potato growing on the archaeological resource and recommendations for the future management of archaeological sites in the arable landscape (Section 8). The report provides, for the first time, some documentation for the process of gradual attrition to archaeological sites in the farmed landscape of Herefordshire. It gives an indicator of the now dramatic and rapid impact that can occur following the advent in the county of industrial- scale potato production. 1 2. Impact of arable farming upon archaeological sites The effects of arable farming upon archaeological features within the landscape have been studied in the past (Darvill, 1987; Darvill and Fulton, 1998; MAFF/OAU, 2000). These studies have demonstrated that continual and intensive ploughing can result in the gradual destruction of sites. However, the nature and extent of damage caused by arable farming varies according to a wide variety of circumstances that may affect individual archaeological sites. Variables such as the topography of a site (whether for instance it is situated at the top, middle or base of a slope) needs to be considered as this may affect the degree to which ploughing may erode archaeological features. Cultural variables also need to be considered such as the type of archaeological site that may be present and how different archaeological features (e.g. walls, ditches or graves) may withstand damage from ploughing. Another factor is the crop to be grown and the form of the machinery necessary to undertake the cultivation, as this will influence the depth to which the soil is disturbed. Potato growing generally requires deep ploughing and a series of cultivation techniques that are beyond the scope of conventional ploughing. Depending upon the soil structure, sub soiling may be required to reduce compacted subsoil and to improve drainage of the soil. This involves breaking up the soil and loosening any compacted subsoil or soil pans and can reach to a depth of 0.3- 0.9m. Potatoes require good seedbeds and de- stoning of the soil may occur so that during the harvest stones do not damage either the crop or machinery. The seedbeds are constructed by a bed- former, which is drawn through the soil to construct the ridges.