Anthropogenic ties to late‐successional structure and composition in four new england hemlock stands
2000
McLachlan, Jason S. | Foster, David R. | Menalled, Fabian
The pace and magnitude of long‐term change in the forests of eastern North America is poorly understood. The current study examines the developmental history of primary Tsuga canadensis stands in central Massachusetts from before European settlement to the present. Through an integrated reconstructive approach employing stand‐level pollen stratigraphies, tree ring chronologies, and long‐term archival records, we show how the characteristic structure and composition of old‐growth forests in southern New England developed in four stands through a history of anthropogenic and natural disturbance, rather than through the gradual process of autogenic succession. Forest composition during presettlement times was distinct at each site and included a variety of successional stages ranging from late‐successional northern hardwood–Tsuga assemblages to assemblages dominated by early successional to mid‐successional taxa such as Castanea, Quercus, and Pinus. Anthropogenic disturbance during the 18th and 19th centuries resulted in novel assemblages dominated by Castanea or Betula. Composition at the four sites converged on the current assemblage dominated by large, late‐successional Tsuga, in response to altered patterns of disturbance in the 20th century. The age of the dominant trees (100–200 yr) and apparent stability of the current forests masks the extent to which their origin is a product of the cultural landscape and is in no way representative of pre‐European forests at these sites.
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