Evidence indicates that an increase in temperature and greater moisture stress will lead to increases in these kinds of stressors, but research to date has examined only a few species. Invasive species are already a persistent and growing challenge across much of the United States. Changes may exacerbate this problem, as warmer temperatures may allow some invasive plant species, insect pests, and pathogens to expand their ranges farther north. Northern Minnesota may lose some of the protection offered by a traditionally cold climate and short growing season. Combinations of factors may also favor invasive species, such as exotic earthworms, and facilitation among several nonnative species. Pests and pathogens are generally more damaging in stressed forests, so there is high potential for these agents to interact with other climate-mediated stressors. Unfortunately, we lack basic information on the climatic thresholds that apply to many forest pests, and our ability to predict the mechanisms of infection, dispersal, and transmission for disease agents remains low. Furthermore, it is not possible to predict all future invasive species, pests, or pathogens that may enter northern Wisconsin and western Upper Michigan during the 21st century.