Ecologist Charlie Cogbill to Present "Original Forests of Vermont"
On Sunday, March 10, at 2:00 pm, ecologist Charlie Cogbill will be at the Woodstock History Center to talk about the Original Forests of Vermont. In his program, he will show how he uses information from old-growth stands, vegetation zones, and historical documents to provide an updated perspective on local forests and vegetation history.
During the 1970s, while Charlie was conducting research at the Hubbard Brook Experimental Forest in Woodstock, New Hampshire, he became interested in the pre-settlement forests that existed prior to the arrival of the European settlers. These pre-settlement forests are important as they are the baseline that researchers use to evaluate the impact of human activity on forests.
While remnants of old-growth forests do provide valuable data and a glimpse into what pre-settlement forests might have looked like, Cogbill notes that these remnant forests are outliers or “oddballs,” for the lack of a better term. For a variety of reasons, early settlers chose not to clear these forests. So while they do provide insights into the more representative, widespread pre-settlement forests that were cleared, by themselves, they may not present an entirely accurate view of what pre-settlement forests looked like.
Consequently, Cogbill looks to other lines of evidence, such as vegetation zones, to glean information. However, complicating the use of vegetation zones as evidence is their dynamic nature due to climate change. As Cogbill notes, the change is not necessarily a simple, linear shift. “Each species is behaving in its own way… You do get changes with climate, but you don’t get the wholesale zonal changes. Or at least the wholesale zonal changes are not as quick. There’s a lag. Trees last for 200 years, and it might take 200 years of warming before the remnant trees are finally clawed loose... It isn’t as simple as it’s been made out.”
Since old growth forests and vegetation zones both have limitations as evidence, Cogbill also looks at historical documents - such as 17th and 18th-century surveys, lotting maps, and journals - for information. Many of these documents, particularly the surveys and lotting maps, provide insight into how newly-formed towns were divided so that the lots could be sold. As a way of demarcating the boundary lines of the lots, early surveyors used piles of stones, stakes, or particular trees as monumentation. These “witness” trees, which marked the boundaries of lots, provide insights into the forests that covered the region before European settlers arrived and began logging and altering the land. Over the past 30 years, by combing through thousands of documents, Cogbill has catalogued more than 350,000 trees from across the Northeast.