Skip to main content
U.S. flag

An official website of the United States government

Dated wood from Alaska and the Yukon: Implications for forest refugia in Beringia

January 1, 1981

Postulations on the existence of forest refugia in parts of Beringia during the last glacial have been, in large part, based on ambiguous evidence. Existing data on radiocarbon-dated and identified fossil wood and macrofossils from Alaska and northwest Canada are synthesized here and are augmented by results of palynological studies in an effort to show the persistence of some, and total extinction of other, tree and large shrub species. Possible dispersal routes taken by species that reinvaded Beringia in postglacial times are also reconstructed from the fossil record. Macrofossil and pollen evidence, when combined with climatic factors, makes cottonwood a good candidate for survival during the last glacial. Larch and aspen are also candidates, though the evidence for them is less positive. Pollen and macrofossils of alder are very scarce in deposits of the last glacial age, and if it survived at all, it was probably in very isolated vegetatively reproducing clones. Shrub birch may have been present in Beringia, but tree birch probably was reintroduced during the Holocene. Spruce also appears to have been absent in Alaska from about 30,000 to 11,500 yr ago and probably reinvaded Beringia from a refugium south of the Laurentide ice sheet. ?? 1981.

Publication Year 1981
Title Dated wood from Alaska and the Yukon: Implications for forest refugia in Beringia
Authors D.M. Hopkins, P.A. Smith, J.V. Matthews
Publication Type Article
Publication Subtype Journal Article
Series Title Quaternary Research
Index ID 70012109
Record Source USGS Publications Warehouse