RADIOCARBON-DATED POLLEN AND SEDIMENT RECORDS FROM NEAR THE BOYLSTON STREET FISHWEIR SITE IN BOSTON, MASSACHUSETTS

A radiocarbon-dated pollen record near the Boylston Street Fishweir si te in Boston, Massachusetts, provides a regional and local record of v egetation changes from the middle Holocene to present. The stratigraph y begins about 5630 +/- 90 yr B.P. with a marine transgression and is continuous up to the historic back-filling of the Back Bay area about 100 yr B.P. When pollen began accumulating at the site, the immediate area resembled the swamp forests growing today in southern New England . Fresh- and brackish-water vegetation was present before the area nea r the site was submerged. While these vegetation changes occurred loca lly, oak forest grew in the region. Correlation of this stratigraphy w ith archaeological data collected from 500 Boylston Street indicates t hat between 4700 and 3700 yr B.P., a number of fence-like alignments ( ''weirs''), were probably placed within existing channels and/or along shorelines to capture fish and other marine animals as they moved wit h the tidal flow. (C) 1994 University of Washington.