Impact models agree that many temperate species will experience increasing suitable habitat and biomass across the Northeast, and that longer growing seasons and warmer temperatures will lead to productivity increases for temperate forest types. For the Northeast, models predict a decrease in suitable habitat for spruce-fir forest, moderate decline in suitable habitat for the maple-birch-beech forest, and expansion of suitable habitat for oak-dominated forest by the end of the century. Habitat fragmentation and dispersal limitations could hinder the northward movement of southern species, despite the increase in habitat suitability. Most species can be expected to migrate more slowly than their habitats will shift. Pests and diseases are also expected to limit some species projected to increase.