An early successional forest is a very young forest characterized by a dense growth of shrubs and saplings. The issue of management for early successional forest is controversial in northern New England because it relates directly to ideas of what “wildlife” is, which pecies “need” special management priority, and the amount, location and techniques of logging that occur or are thought necessary.
The vegetation structure of early successional forest is very different from that of older forests, and it provides distinctly different wildlife habitats. Some wildlife are either closely associated with early successional forest or tend to have higher populations in it. People who argue for creating more early successional forest usually say that certain birds and mammals need young forest habitat to achieve full reproductive potential, and some of these species are experiencing population declines. Other conservation professionals are skeptical of this argument because it fails to consider the status of the region’s forests and native species in an appropriate historical context.
There is no doubt that the amount of young forest in northern New England declined substantially in the latter half of the twentieth century, compared to amounts in the mid-nineteenth to early twentieth century. There
is also no doubt that species such as chestnut-sided warbler, grouse, cottontails, snowshoe hare, woodcock and deer, do well where early successional forests exists.
What is not clear is whether we should manage for current or larger population sizes of these and other species associated with early successional habitat, even though they were less abundant prior to major human alteration of the landscape.
Most of New England was deforested by the late nineteenth and early twentieth centuries. While fields were re-growing to forest approximately 50 to 100 years ago, there was an abundance of early successional habitat. Naturally, populations of species associated with early successional habitat increased substantially during that time compared to their numbers before European settlement.
Wildlife requiring early successional forest in moderate- to large-sized patches, however, would not have found extensive habitat in northern New England prior to the middle of the nineteenth century. Historic ecology research from northern New England and upstate New York has shown that at the time of presettlement surveys (which were conducted prior to extensive forest clearing), the eastern northern hardwood forest had only about one percent of the land in young forest. That one percent existed in small to medium-sized patches created by individual tree deaths, blowdowns, downdrafts during storms (microbursts), ice storms, the inland remnants of hurricanes, and beaver.
Does this mean we should not maintain habitat for species associated with early successional forest? Not necessarily. But it does indicate we should think carefully about why and where we may choose to create such habitat in a landscape that was naturally one of almost total forest cover, dominated by what we now call “old-growth.”
Unlike species that thrive in early successional forest, some species native to this region are quite sensitive to extensive deforestation, habitat fragmentation, and the creation of abundant edge habitat (forest that is bordered by openings, such as pastures, abandoned fields, powerline corridors, clearcuts, etc.). They include various birds, mammals, amphibians, insects, vascular plants, mosses, fungi, lichens, and bacteria. Thus, a conflict arises between managing for an intact forest ecosystem as optimal habitat for forest-interior species, and managing for early successional forest and species that thrive in it.
One way to partially reconcile this conflict is to manage for early successional forest in parts of the landscape that are already fragmented and which are therefore not presently well-suited to maintaining interior forest species and processes. We can manage for early successional forest in landscapes that are now a mix of open land and forest patches, and thus leave the older, unfragmented forests alone.
As private lands account for most of the patchwork landscape of abandoned fields, young forest, and small, older forest fragments, private lands make sense as the locus of most early successional habitat management. The maintenance and restoration of older, late successional habitat should be the focus of management on public land, where there is potential for maintaining and creating large tracts of unfragmented forest.
Because public land itself is relatively scarce in New England, however, the long-term restoration of native ecosystems driven by natural dynamics—if that is a goal of conservationists and of society—will require that some private lands, too, be conserved for the old forests that someday will return.
Marc Lapin is an ecologist who leads the Champlain Valley Clayplain Forest Project.
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