Forest Vulnerability to Climate Change and Tree Pests at Marsh-Billings-Rockefeller National Historical Park
Climate change is affecting species and resources across National Parks. Shifting climatic conditions are likely to result in novel species assemblages; this means that some species currently present within parks may decline or disappear while more southerly or warm-adapted species may gain substantial habitat. Stewarding forests for continuous change is a challenge for park managers; however, understanding projected rates and directions of forest change should facilitate monitoring and management efforts on park lands and across the broader landscape. To support climate change adaptation within the forest management plan for Marsh-Billings-Rockefeller National Historical Park, we analyzed projected changes in tree habitat suitability for 80 trees species for three future periods (2040, 2070, and 2100) and also assessed recent and projected tree pest impacts to park forests. For tree habitat, we present model output from two climate scenarios, the ‘least change’ and ‘major change’ scenarios that represent a rough bound of plausible future conditions. General trends in the data indicate strongly decreasing potential habitat suitability for 10 species (12% of species), minor change for 24 species (29% of species), and large increases or new habitat for 48 species (59% of species). Some northern tree species, including fir, aspen, and paper birch, have moderate to strong decreases in suitable habitat under both future scenarios whereas most temperate species currently present retain suitable habitat. Under the warmest scenario, several oak, hickory, and pine species uncommon or absent in the park gain suitable habitat in central Vermont in the coming decades. Forest pest impacts have been relatively moderate over the past 15 years, though expansion rates of species such as hemlock woolly adelgid and emerald ash borer threaten the park in the next two decades. The combination of rapid climate change and tree pests may accelerate decline of some tree species and inhibit other species from occupying climatically suitable habitat. Results presented here will be used by managers at Marsh-Billings-Rockefeller NHP as they adapt their forest management plan to achieve desired conditions in a continuously changing world.