Map of Pennsylvannia Regions.

Pennsylvania's forests will be affected by a changing climate and other stressors during this century, but individual tree species will respond uniquely to climate change, depending on their particular silvics and ecological tolerances. These handouts summarize general climate change projections for tree species across several landscapes in the region based on future projection models from the USDA Forest Service’s Climate Change Tree Atlas. It’s best to think of these projections as indicators of possibility and potential change, and that the general trends form these models can be combined with local knowledge and management experience to judge risk on a particular site.

The following handouts provide summarized lists of projected tree species responses to climate change. These handouts were updated in 2024 to standardize and refine the capability tables on the first page, clarify the role of the USDA Forest Service as core authors and distributors of the model results, and adhere to new accessibility standards.

Please note: The Lake Erie and Ontario Lake Plain (Subregion 2) and the Coastal Plains (Subregion 6) are too small for analysis; data for these areas are best combined with the broader Mid-Atlantic region.

The Mid-Atlantic Forest Ecosystem Vulnerability Assessment and Synthesis contains additional information on observed climate trends and a range of projected future climates for the region. This document also describe many potential climate change impacts to forests and summarize key vulnerabilities for major forest ecosystems. The Climate Change Tree Atlas website contains more detailed information on projected changes for 125 eastern tree species, as well as additional regional summary tables for states, watersheds, and urban centers.

 

Heat and Hardiness Zones

Some trees were not modeled by Tree Atlas. For these species, climate change effects can be assessed by examining future projections of hardiness zones and heat zones for regions of Pennsylvania (right). The climate change effect was calculated by comparing the species’ published heat zone tolerance to the map of projected heat zones under two climate scenarios. As temperatures increase, it is expected that hardiness and heat zones will shift by up to 3 hardiness zones and 5 heat zones by the end of the century.

Pennsylvania heat and hardiness zones informational handout