Determining the age of the mid-Holocene Tsuga canadensis (hemlock) decline, eastern North America

Pollen counts and radiocarbon age determinations from 60 sites in eastern North America are used to determine the age of the mid-Holocene Tsuga canadensis decline, and to analyse the errors associated with such age estimation. The age is determined as 4750 C-14 yr BP with a standard error of the mean of about 50 years. Despite the quantity of data available, large uncertainties in the choice of age-depth model make it impossible to determine a more precise age for this event. It is likely that there are similar problems, or worse, with attempts to determine the age of other Holocene events. Within the limitations of the available data set, the Tsuga canadensis decline was synchronous across the whole of its range.