Project Description. Widespread mortality of black walnut, Juglans nigra, in the western U.S. has been attributed to an insect-mediated disease known as thousand cankers disease (TCD). This disease manifests when the vector, Pityophthorus juglandis (walnut twig beetle), inoculates trees with a fungus, Geosmithia morbida. TCD was documented from black walnut in its native range in the eastern U.S. in 2010. However, the symptomology of the disease has not been as acute as in the western U.S. Greater environmental stress in the western U.S. may account for greater disease severity. Thus, under what scenarios would symptomology be more acute and mortality more widespread in the eastern U.S.? Ecological niche modeling will be combined with climate change models to characterize conditions that may contribute to greater infection and mortality in the eastern U.S. The resulting models will allow scientists and resource managers to consider management strategies for future forests.