6000 years of forest dynamics in Suserup Skov, a seminatural Danish woodland

1 The history of a forest stand over the last 6000 years has been reconstru cted by studying pollen, macrofossils and charcoal from a small, wet hollow in Suserup Skov on the island of Sj ae lland in eastern Denmark. 2 The earliest recorded forest was Tilia-dominated but contained an intimat e mixture of many different tree species that included Acer campestre, A. p latanoides, Alnus glutinosa, Betula pubescens, Corylus avellana, Frangula a lnus, Fraxinus excelsior, Malus sylvestris, Populus tremula, Pinus sylvestr is, Quercus robur, Q. petraea, Salix spp., Sorbus aucuparia, Tilia cordata and T. platyphyllos. The preserved fruits of T. platyphyllos confirm its hi therto doubtful status as a native member of the Danish flora. 3 The present-day woodland developed after a period of intensive anthropoge nic disturbance between approximate to 600 bc and ad 900, during which time open canopy conditions prevailed at Suserup. Fagus sylvatica and Fraxinus excelsior are the dominant trees at present, together with some Quercus rob ur and Ulmus glabra. 4 Charcoal was present in the sediments from most time periods except at th e Ulmus decline. In the last 1000 years of the sequence - the period of Fag us dominance - charcoal counts were consistently low. 5 Pinus sylvestris was a natural component of this primarily deciduous fore st, and the last macrofossil find dates from c. ad 900. Macrofossil Pinus c one scales recorded c. ad 1800 originate from planted individuals. Prior to Fagus dominance, the forest had an open structure partly caused by frequen t, low-intensity fires associated with the presence of Pinus sylvestris. 6 The replacement of Tilia by Fagus in this forest was catalysed by human a ctivity. If the forest had not been so disturbed, the rich diversity of tre es would most probably have persisted up to the present time, with only a m oderate-sized Fagus population.