A multidiscipinary project is in progress to determine the factors controlling forest vegetation over the last 400 years at Itasca State Park, northwest Minnesota. The approach is to reconstruct from independent lines of evidence forests, including patterns of composition, recruitment, growth, and mortality, and physical environments, including climate and fire, in a detailed fashion across a one km2 study area. Patterns within stands will be agglomerated to document both local stand and landscape patterns through the past. Methods include analysis of fossil pollen, charcoal, loss-on-ignition, and thin-sections of laminated lake sediments, fire-scars of 400 year old red pine trees, stand age structures, tree growth via ring widths, soils, light regimes, and modes of regeneration and mortality. Results will demonstrate many of the important influences of changing physical environments on vegetation that can be used for forest management and prediction of responses to changing climate, land- use, and fire regimes.
