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A palaeoecological study was performed in the northern Scandinavian mountain range in Sweden. The aim was to study vegetation changes and shifts in forest limit altitudes during the last 5000 years in a tree-less archaeological site (Adamvalta) situated below the regional forest limit, and in a forested reference area with similar geological features but without archaeological evidence of human presence (Ajdevaratj). The suitability of uncritically using forest limit changes as indicators of climate change is also discussed. The study included analyses of pollen, pollen accumulation rates (PAR), macrofossils and loss-on-ignition. The results indicate vegetation changes in both areas plausibly caused by climate c. 3800 BP and c. 500 400 BP. However, at Adamvalta, settlements were established c. 1300 750 BP, close to the mountain birch ( Betula pubescens ssp. czerepanovi) forest limit. About 800 BP, the birch forest cover at Adamvalta decreased and the vegetation developed into an alpine heath, as a result of human-induced deforestation. The following ‘Little Ice Age’, in combination with human impact from the sixteenth century onwards, prevented forest recovery, and the site remains treeless. Such vegetation changes were not recorded at Adjevaratj. It is deduced that the present position of the forest limit at Adamvalta is governed by a combination of factors where previous human impact and climate have been the major driving forces determining the long-term vegetation development. Hence, a thorough knowledge of the site history is important when forest limits are used as a proxy for climate change.

1 The history of a forest stand over the last 6000 years has been reconstructed by studying pollen, macrofossils and charcoal from a small, wet hollow in Suserup Skov on the island of Sjaelland in eastern Denmark. 2 The earliest recorded forest was Tiliadominated but contained an intimate mixture of many different tree species that included Acer campestre , A.