The Management of Arable Land from Prehistory to the Present: Case Studies from the Northern Isles of Scotland Erika B. Guttmann, 1, * Ian A. Simpson, 2 Donald A. Davidson, 2 and Stephen J. Dockrill 3 1 Department of Engineering, Centre for Sustainable Development, University of Cambridge, Trumpington Street, Cambridge CB2 1PZ, United Kingdom 2 Department of Biological and Environmental Sciences, University of Stirling, Stirling FK9 4LA, United Kingdom 3 Department of Archaeological Sciences, University of Bradford, West Yorkshire BD7 1DP, United Kingdom The arable soils from two multiperiod settlements were analyzed to identify changes in agri- cultural methods over time. The settlement middens were also analyzed to determine whether potential fertilizers were discarded unused. Results suggest that in the Neolithic period (~4000–2000 B.C. in the UK) the arable soils at Tofts Ness, Orkney, and Old Scatness, Shetland, were created by flattening and cultivating the settlements’ midden heaps in situ. The arable area at Tofts Ness was expanded in the Bronze Age (~2000–700 B.C. in the UK), and the new land was improved by the addition of ash, nightsoil, and domestic waste. Cultivation continued briefly after the fields were buried in windblown sand in the Late Bronze Age or Early Iron Age, but by the Early Iron Age cultivation ceased and organic-rich material was allowed to accu- mulate within the settlement. By contrast, at Old Scatness, arable production was increased in the Iron Age (~700 B.C.–A.D. 550 in Scotland) by the intensive use of animal manures. The results indicate that during the lifespan of the two settlements the arable soils were fertilized to increase production, which was intensified over time. © 2006 Wiley Periodicals, Inc. INTRODUCTION The difficulty of producing adequate food supplies for a growing population has been a fundamental problem since the beginnings of agriculture. It can be addressed by either increasing arable production by the expansion of arable land, or by inten- sifying production on land already under cultivation (Boserup, 1965). Production can be increased by fertilizing the soil, or by improving the type of fertilizers which are applied. A wide range of fertilizers can be used to improve soil quality, but the materials which are actually available will depend on the local environment and whether or not domestic livestock are kept. The available fertilizers are not always used, whether from ignorance or indifference, and the agricultural survey of Britain Geoarchaeology: An International Journal, Vol. 21, No. 1, 61–92 (2006) © 2006 Wiley Periodicals, Inc. Published online in Wiley Interscience (www.interscience.wiley.com). DOI:10.1002/gea.20089 *Corresponding author; E-mail: ebg24@cam.ac.uk.