|Old Stone Walls: A New England Heritage
Who living in New England today has not seen stones emerge through paved roads, inexorably lifted by frost heaving, bursting the smooth surface like some primeval force laughing at the puny efforts of civilization? It's easy to conclude that this process is inevitable, part of local geology.
But I just learned it's the result of the colonists' clearing the original forest. In a mature, undisturbed forest, the layer of organic litter insulates the soil so well it does not freeze at this latitude. But after the cleared land began freezing, within a few decades stones started emerging from below the subsoil.
In Stone by Stone; The Magnificent History in New England's Stone Walls, Robert M. Thorson describes first the geological origins of the stone we see now; then he examines the historical record of how it became walls: books published by travelers to New England, private journals, early tracts on farming, town census records, laws about fencing, survey documents....
Thorson's main interest is the old walls surviving from the period when most were built here: the days of the family farm as the center of New England life roughly 1775 to 1825. These were made by throwing the rock into a pile, in the process of clearing fields; ergonomics resulted in these walls reaching only thigh-high.
But he also looks at the craft of building walls more intentionally. The principles of wall building, he comments, are "similar to the natural laws of the formation of mountains." He explains that mortared walls survive poorly here not only because they're less flexible than dry walls, but also because the alkaline mortar is attacked by acids in fallen leaves, our soil, and even the native granite itself.
He considers the emotional and artistic impact of New England stone walls, musing on how they became popular in poetry, paintings, novels, photos, and oral tradition. "Eventually," he comments, "stone walls would become the signature of the New England interior landscape."
More than part of our cultural heritage, our old walls have also become habitats for vegetation and animal life uniquely suited to the dry conditions they create, increasing the biodiversity of our ecosystem.
But the popularity of our old stone walls now endangers them, as people mine the old to build anew. This is natural, but perhaps shortsighted. Thorson encourages us to preserve them where we can, as valuable landforms in their own right; as part of our heritage, our sense of place.
© Copyright 2003 Catherine Holmes Clark