The rock walls found in every part of the woods in all of New England except northern Maine, are a reminder that virtually all of New England was used for field or pasture at one time in the not too distant past. One might hope that analysis of these forests would provide a stable endpoint for conservation choices, but even the old-growth forests of today are quite different from those of the past.
Disturbances affect primarily the growth of the overstory stems.
In the 1920's hemlock suffered from a bracket fungus, Armillaria mellea , while porcupines caused extensive damage to beech and birches. Of the remainder about half was relatively undisturbed and about half was severely damaged, with the severity of damage controlled largely by local topography.