Dead trees in coastal swamps from various sites in southwestern Washington State have been dated using the tree-ring technique. At each of the four sites shown on the map above at least one of the trees has an outer growth ring which corresponds with the 1699 growing season. It is concluded by Yamaguchi and co-workers that these trees died sometime between the end of the growing season in 1699 and the start of the growing season in 1700.
This image used with the permission of Brian Atwater, University of Washington.