Gap Dynamics or More Than That? Long-term Development of Mixed Hardwood Forests


  • Neil Pederson Harvard Forest


It is not unreasonable to think that sustainable management of Northern Hardwood Forests would be partly informed by long-term data on forest dynamics. Most measures and observations of forest dynamics are set by grants (3-5 years), the careers of scientists and managers (20-40 years), or, less frequently, long-term plots approaching 100 years or so in age. While these data and observations are incredible and useful, they represent only a fraction in the lifetime of most trees and far less than what I’d estimate the length of forest generation to be. We have analyzed tree-ring records from local to subcontinental scales that cover the three to five centuries in mixed hardwood forests. In no way do these analyses supersede the great data mentioned above. They do color in the natural and understandable gaps in knowledge of forest processes and dynamics. We have identified climate as one potential synchronizer of forest dynamics over subregional scales that, together with gap dynamics and many other types of drivers, helped to create today's old-growth forests. Put another way, while the classical theory on the cyclical nature of Beech-Birch-Maple gap dynamics in Northern Hardwood Forests are likely a very real phenomenon, other drivers at longer time scales and broader scales might suddenly push the trajectory of these forests at various points in time into new structures or compositions.

Author Biography

Neil Pederson, Harvard Forest

Neil Pederson is a forest ecologist at the Harvard Forest who studies the dynamics and long-term development of forests from individual trees to regions and subcontinents. Neil is especially curious about the growth, longevity, and ecology of broadleaf trees. Neil earned an associate degree at SUNY-Morrisville, a bachelor’s degree at SUNY-ESF, and an MS at Auburn University studying an old growth bottomland hardwood forest in South Carolina. After a stint as a tree-ring technician at the Tree-Ring Laboratory of Lamont-Doherty Earth Observatory assisting research on climate change in Mongolia and Russia, he earned a PhD at Columbia University studying forest ecology and climate in the eastern US. Before starting at Harvard Forest in Fall 2014, Neil was an assistant professor in biology at Eastern Kentucky University and a research professor at Lamont Doherty Earth Observatory.   Neil is studying the impacts of climate on the lives of trees and the development of old-growth forests in the Northeastern US.