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Harvard Forest Symposium Abstract 2008

• Title: The Tannery site at Harvard Forest: Two hundred years of human impact on the vegetation
• Primary Author: Elisabeth Almgren (University of Uppsala)
• Additional Authors: David Foster (Harvard University); Brian Hall (Harvard Forest)
• Abstract:

  The Tannery site at Harvard Forest is located at the southern end of Prospect Hill. It was established as a tannery by John Sanderson in 1792 as an additional part of his farming operation and continued to be used until the late 19th Cent. The site is presently forested, but many features remain from the original tannery, such as a dam, a millpond, a stone-lined headrace, house foundations and a large well.
  
  The present study of historical changes in the surrounding vegetation is part of a larger project involving historical research, archaeological excavations and mapping of the site that was initiated in 2007 by David Foster. The aim is to do a social and historical study of the Harvard Forest tannery and put it into a larger economic and historical perspective of 19th Cent. New England tanneries.
  
  Part of the project relates to the investigation of the impact on the local vegetation resulting both from farming and from the tannery operation with its need for large supplies of hemlock bark. The dam in the middle of the Tannery site was cored in the fall of 2007 and a 1.75 m long sediment core was retrieved. The pollen record is presently being analyzed at closer intervals to increase the time resolution, but the main outline of the last c. 200 years of vegetation changes is finished.
  
  The dam was probably established as part of the construction of the tannery and consequently, the sediment is only c.200 years old. The bottom sample shows high amounts of hemlock that decline over a short period and an associated increase in ash, chestnut, and red maple. A clear increase in alder follows and could signify the vegetation development around Gould bog, situated above the Tannery dam. Rye is grown in the nearby fields and show up in the pollen record at this time and pollen percentages of grasses are high, pointing to an open farm landscape surrounding the Tannery site. Further clearings and farm activities are shown by an increase in herbs (e.g. Rumex, Ambrosia, and Plantago lanceolata). The peak of the open landscape appears mid-way up the core with peaks in herbs, grasses, and cereals. Hemlock reaches its lowest values at this time and is probably due to the continuous need for hemlock bark to the tannery operation. Reforestation follows with increase in pine and chestnut, followed by the drop in chestnut after it has been attacked by Chestnut blight. The first pollen of corn (Zea mays) appears towards the top of the sediment core and pine increases due to plantations in the early 20th Cent.
  
  

• Research Category: Historical and Retrospective Studies