The Nature Conservancy of Vermont partnered with Dr. Shelly Rayback’s Dendrochronology class last fall to use the techniques of dendrochronology (the study of tree rings) to understand how trees respond to and record a measure of their environment over time.  This service learning partnership was one of four classes supported by a sub-grant through Northern New England Campus Compact and the Environmental Protection Agency.

The study focused on a stand of shagbark hickory (SBH) located on the Raven Ridge property in northwestern Vermont.  The Nature Conservancy (TNC) was particularly interested in understanding the response of shagbark hickory to 1) the climate; 2) the forest stand composition and structure; and 3) the land use history over time; and how these factors might influence a maternal roosting colony of Indiana bat (who roost under the peeling bark of the tree during the summer).

Students delivered a final report to TNC with results showing a negative response to warmer temperatures and low levels of precipitation, which was unexpected at this northern location.  This time series was correlated with local meteorological data to show that this stand of trees is being stressed by rising temperature and more arid conditions.  Student hypothesized that if temperatures continue to warm, accompanied by more frequent drought, this particular stand of SBH may be in danger and thus, the Indiana Bat, an endangered species, may lose an important roosting site at Raven Ridge.