Robert Thorson, University of Connecticut – Stone Wall Science

Stone walls are an important landmark in the Northeastern U.S. But what can they tell us?

Robert Thorson, professor of earth sciences at the University of Connecticut, explores the history.

Robert M. Thorson is Professor of Earth Sciences at the University of Connecticut, where he juggles teaching, writing, mentoring, committee work, and community engagement.  He’s a Midwestern native, turned Northwestern geologist, turned Northeastern academic.  His current scholarly interest is the interweave between Anthropocene archaeology, environmental history, and American literature that creates New England’s unique sense of place.  He commutes to work on a woodland trail. He teaches three Earth science courses for UConn’s Honors Core Curriculum and coordinates its Stone Wall Initiative within the Connecticut State Museum of Natural History.

Stone Wall Science

Criss-crossing rural New England is a latticework of abandoned stone walls built mainly during a wave of agricultural settlement before the Civil War.  Though hefted by human muscle, this extensive gridwork of stone was –at a deeper level–  created naturally as an emergent phenomenon akin to mud-cracks in geometry and ant-hills in mechanics.

The human story began when the region’s upland glacial terrain was cleared of old-growth forests to make room for pastures, fields, meadows, and orchards. Enhanced exposure to cold, wind, and runoff during the Little Ice Age gradually concentrated stone on the surface.  Being in the way, it was scuttled outward to the edges of land parcels where it was dumped, and often crudely stacked.  Many of these linear landfills were later upgraded into higher, better-built walls to maximize arable space, mark property boundaries, and replace rotting wood as a fencing material.  When the agricultural economy went bust, tens of thousands of farms were abandoned and reclaimed by weedy trees, leaving an extensive network of hyper-concentrated stone beneath a 20th century woodland canopy. 

The cultural significance of New England’s stone walls has long been appreciated by the humanities.  Now, scientists are starting to take notice.

To geologists, they are signature landforms created by a regionally-unique trinity of hard crystalline bedrock, glacial soils, and the human agency.  To archaeologists, they are artifacts that enrich a history otherwise told by documents.  To ecologists, they are habitats, elevated volumes of of dry, rocky terrain in an otherwise lower, moister, organic world …. hiding places, corridors, and edges.

Each wall in the woods is a local dryland.  The counterpart to a local wetland.  Wetland science is robust.  Dryland science is not.  The time has come for greater parity.