As we make our way up the trail, the old-growth evangelist, as Leverett is often called, explains that though individual trees in New England have famously escaped the ax—the nearly 400-year-old Endicott pear tree in Danvers, Massachusetts, comes to mind—when ecologists discuss old growth, they’re talking not about single specimens but about systems, about uninterrupted ecological cycles over time. These are forests sustained by myriad sets of biological processes: complex, interconnected systems of perpetual renewal. While there is no universally accepted definition of old growth, the term came into use in the 1970s to describe multispecies forests that had been left alone for at least 150 years.
And that’s exactly what we’re seeing at Ice Glen, so-named for the deposits of ice that lived in its deep, rocky crevasses well into the summer months. Hemlocks hundreds of years old loom over gnarled and thick-trunked sugar maples as sunlight thickens into shadow through a cascade of microclimates. White pines reach skyward past doomed ash trees and bent-limbed black birch; striped maples diffuse a chlorophyll green across the forest floor through leaves the size of lily pads, while yellow birch coils its roots around lichen-covered rock; long-ago fallen, moss-heavy nurse logs return to earth only to re-emerge as philodendron and hemlock. Elsewhere, maidenhair, blue cohosh and sassafras abound, auguries of a nutrient-heavy, fertile forest floor. Walking through woods like these, the kind of hemlock-northern hardwood forests that once thrived in the Appalachians from Maine to North Carolina, is an encounter with deep time.
— Old, Primeval Forests May Be a Powerful Tool to Fight Climate Change