Parameterization of a Forest Growth Model for Addison County, Vermont, Poster 23

Forest dynamics modeling is a powerful tool for understanding and anticipating long-term changes in forest composition and structure. SORTIE is a spatially-explicit individual-tree based model composed of four separate... [ view full abstract ]

Forest dynamics modeling is a powerful tool for understanding and anticipating long-term changes in forest composition and structure. SORTIE is a spatially-explicit individual-tree based model composed of four separate submodels that describe interactions of light, growth, mortality, and seedling recruitment to ultimately determine local stand structure and forest composition. This past fall and winter, tree increment cores and seedling stem cross-sections were collected from forests in the Green Mountains to parameterize the growth submodel. Using tree rings to infer growth, species-specific mathematical functions were derived for diameter-dependent radial growth of mature trees and light-dependent growth of seedlings. Species chosen represent major components of local forests, including sugar maple, yellow birch, white pine, eastern hemlock, and American beech. Outputs of the SORTIE model, once all four submodels are parameterized, can provide valuable insights into the response of Addison County’s mid-elevation forests to a changing climate, selective harvesting, disturbance, and mortality of major component species in response to invasive pests and pathogens.