Lake sediment cores from two lakes yielded pollen profiles which reflect vegetational and climatic changes since deglaciation. Radiocarbon dates from specific levels outline the chronology. Correlation of pollen zones between the two profiles indicate the degree of error in the anomalously old dates from one of the sites. Total absolute pollen frequencies are used to aid in interpretation.Following deglaciation a tundra environment prevailed until about 12 000 radiocarbon years B.P. This was followed by a transition zone in which Betula and Populus were abundant. About 12 000 years B.P. Picea increased markedly and remained a dominant part of the vegetation until 9500 years B.P. when Pinus and Quercus became prominent. Tsuga and various hardwood genera predominated after 6500 years B.P. An increase in Picea and decline in Tsuga and some hardwood genera produced the forests which prevailed when the area was settled.

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