%0 Research article
%T Tree age distributions in old-growth forest sites in Vienansalo wilderness, eastern Fennoscandia
%A Kuuluvainen, Timo
%A Mäki, Juha
%A Karjalainen, Leena
%A Lehtonen, Hannu
%D 2002
%J Silva Fennica
%V 36
%N 1
%R doi:10.14214/sf.556
%U https://silvafennica.fi/article/556
%X The age and size of trees was sampled and measured on eight sample plots  (0.2 ha each) within a Pinus sylvestris -dominated boreal forest  landscape in Vienansalo wilderness, Russian Karelia. The fire history of  these plots was obtained from a previous dendrochronological study. All  the studied sample plots showed a wide and uneven distribution of tree  ages, but the shape of the age distributions of trees as well as tree  species composition varied substantially. Trees over 250 years of age  occurred in every studied plot, despite its small size. This suggests  that old Pinus were common and rather evenly distributed in the  landscape matrix. The oldest Pinus tree was 525 years of age. The  correlations between tree age and size were often weak or even nil. In  Pinus the correlation between age and diameter was stronger than that  between age and height. In the dominant tree species Pinus and Picea,  the largest trees were not the oldest trees. The tree age distributions  together with the fire history data indicated that the past fires have  not been stand replacing, as many of the older Pinus had survived even  several fires. Tree age classes that had regenerated after the last fire  were most abundant and dominated by Picea and/or deciduous trees, while  the trees established before the last fire were almost exclusively  Pinus. The results suggest that periodic occurrence of fire is important  for the maintenance of the Pinus-dominated landscape. This is because  fire kills most Picea and deciduous trees and at the same time enhances  conditions for Pinus regeneration, facilitated by available seed from  the continuous presence of old fire-tolerant Pinus trees.