Variation of carbon age of fine roots in boreal forests determined from ^sup 14^C measurements

The main objectives of this study were to determine how the carbon age of fine root cellulose varies between stands, tree species, root diameter and soil depth. In addition, we also compared the carbon age of fine roots from soil cores of this study with reported values from the roots of the same diameter classes of ingrowth cores on the same sites. We used natural abundance of ^sup 14^C to estimate root carbon age in four boreal Norway spruce and Scots pine stands in Finland and Estonia. Age of fine root carbon was older in 1.5-2 mm diameter fine roots than in fine roots with