Pollen analysis in the context of clearance cairns from boreal forests e a reflection of past cultivation and pastoral farming Anette Overland, Kari Loe Hjelle * University Museum of Bergen e The Natural History Collections, University of Bergen, Post Box 7800, N-5020 Bergen, Norway article info Article history: Received 24 April 2012 Received in revised form 17 August 2012 Accepted 22 August 2012 Keywords: Clearance cairn fields On-site pollen analysis Forested marginal areas Agricultural history Eastern Norway abstract The former agricultural use of two sites located in the boreal forest of eastern Norway is investigated through pollen analysis. A peat profile was taken from the vicinity in each of two clearance cairn fields where several cairns were analysed for pollen. The pollen samples from the peat profiles give an envi- ronmental context for the pollen samples from the clearance cairns, and this combination of samples assists in evaluating the management practices that were in place on the cairn fields during different time periods. In both study areas cultivation layers under the clearance cairns are dated to the Late Roman Iron Age (cal. AD 200e400), while the oldest clearance cairns are dated to the Migration period (cal. AD 400e570), and a second phase of clearance cairn establishment is dated to the Medieval period (cal. AD 1030e1537). Abandonment of the two cairn fields is dated to c. AD 1700. Pioneer trees were a feature on or around the clearance cairn fields during most of the Iron Age, whereas the cairn fields were more open in medieval times. The investigation suggests that cereal cultivation on the clearance cairn fields is difficult to detect in local peat deposits, and that caution is needed when interpreting lack of Cerealia pollen. Management practices on the cairn fields are discussed and a change in management practice is indicated in association with medieval intensification. Ó 2012 Elsevier Ltd. All rights reserved. 1. Introduction Palynological research into long-term landscape change and human impact on their surroundings is often based on regional pollen records from lake or bog deposits (e.g. Berglund, 1991). Recent research has focused on improving our understanding of pollen signals and how spatial patterns of land-use and vegetation types are recoded in sedimentary basins (e.g. Bunting, 2008; Gaillard et al., 2008; Hellman et al., 2009a, 2009b). As wetlands are sometimes not optimal archives when investigating fine-scale land-use and human activity in the landscape, on-site pollen data from archaeological sites can be important. Pollen records from archaeological sites are often distorted by poor pollen preservation and/or uncertain pollen stratigraphy (e.g. Bunting and Tipping, 2000; Dimbleby, 1985; Tipping, 2000; Tipping et al., 2009) and a combination of pollen data from archaeological sites and nearby local wetlands has proven useful when reconstructing former human activity and land-use (e.g. Emanuelsson, 2001; Hjelle et al., 2012; Overland and Hjelle, 2009, 2007; Overland and O’Connell, 2011, 2008). In this paper we show how, in marginal settings, a peat bog or a forest hollow may detect nearby human activity and land-use (at 25e80 m distance), but fails to register types of activity such as cereal cultivation as distinctly as on-site pollen analysis from archaeological layers, despite the poor pollen preservation in these layers. A combination of pollen records in an archaeological context and nearby peat profiles is complementary and provides a more detailed picture of local vegetation, farming activity and human impact than any record by itself. This study contributes to the evidence of past diverse agricultural landscapes within marginal areas, which is difficult to detect unless on-site sampling of archaeological sites is achieved. The study also highlights the care needed when interpreting lack of Cerealia pollen, as the wetland profiles show a clear deficiency in detecting nearby cereal cultivation. In this study prehistoric and historical clearance cairn fields situated in present-day coniferous forests have been investigated in order to study management practices of these arable remnants. In eastern Norway, as well as in south and middle Sweden, large fields with clearance cairns reflecting past cultivation have been recog- nized since the time of Carl Linnæus (Linnæus, 1751). Recent research has dated clearance cairn fields to several time periods: Late Bronze Age, Iron Age, Medieval period, and even modern times (e.g. Gren, 2003, 1989; Holm, 2007; Lagerås, 2000, 1996; Lagerås * Corresponding author. Tel.: þ47 55583323; fax: þ47 55589667. E-mail addresses: Anette.Overland@gmail.com (A. Overland), Kari.Hjelle@ um.uib.no (K.L. Hjelle). Contents lists available at SciVerse ScienceDirect Journal of Archaeological Science journal homepage: http://www.elsevier.com/locate/jas 0305-4403/$ e see front matter Ó 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.jas.2012.08.031 Journal of Archaeological Science 40 (2013) 1029e1041