Changing Climate, Changing Trees

Forest is the dominant native habitat of the LEAP region, and our forests will be altered significantly by climate change in the coming decades. More than a third of the region’s tree species will be less able to survive here by the end of the century, according to a study of the LEAP region by scientists at the U.S. Forest Service Landscape Change Research Group.

How our climate could change

The study developed two customized climate models for the region -- one projecting future conditions based on a moderate level of global greenhouse gas concentrations (the so-called RCP 4.5 concentration pathway) and a second one based on high concentrations (a pathway called RCP 8.5 which assumes little is done to reduce emissions in the coming decades). Because a higher concentration of greenhouse gases means the Earth’s atmosphere traps more heat, the RCP 8.5 model predicts greater changes in the region’s climate.

Here is how the two models predict the region’s climate will change from a baseline of 1980-2009 to the end of this century:

  • Annual precipitation: Increase of 3.9 inches with RCP 4.5 and 5.2 inches with RCP 8.5.
  • Mean annual temperature: Increase of 6.7° F with RCP 4.5 and 11° F with RCP 8.5.
  • Plant hardiness zones: A shift of one full zone with RCP 4.5 and two full zones with RCP 8.5.
  • Heat zones (the average number of days above 86° F): Increase from 20 to 61 days annually with RCP 4.5 and 129 days annually with RCP 8.5 (the latter would mean more than four months a year of sweltering weather).

Below are links to map views that show how these climate changes could occur in different parts of the LEAP region. For each climate parameter there are three maps -- the 1980-2009 baseline, the RCP 4.5 projection for the end of the century, and the RCP 8.5 model for the end of the century.

The bottom line of these climate models is that our region’s climate is very likely to change dramatically by end of this century if greenhouse gas emissions are not rapidly curtailed.

How trees could respond

After modeling future climate conditions, the study then evaluated how the region’s changing climate could impact trees. Which tree species will have the capability to cope with the changes? And which trees will be able to shift their ranges to find suitable habitat in the future?

Below are links to pages with data tables summarizing how tree species are likely to respond. The tables cover the region as a whole, as well as smaller parts of the region (subregions, watersheds, and one-degree grids of latitude and longitude). The breakdown into smaller areas provides insights into the spatial variability of the region -- allowing you to explore how a particular tree species might do all right in some parts of the region but not others.

The tables are complex, and there are a number of caveats about how to interpret them. So it’s recommended that you check out the guidance document below before looking at the tables.

Generalizations about tree impacts

One must be cautious about making generalizations about the future of trees at the regional scale. Some trees that are predicted to fair poorly might persist for a long time in places with special micro-climates. Or an abundant species could be wiped out unexpectedly by a new pest, such as happened recently with ash trees and the emerald ash borer. Or the climate data might not account very well for special conditions near the shore of Lake Erie.

Nevertheless, here are some tentative, general predictions about the tree species likely to do well -- or not -- in the LEAP region as the climate warms in the coming decades.

Tree species that were modeled to do well with climate change:

  • American elm
  • northern red oak
  • yellow-poplar
  • white oak
  • black oak
  • red maple
  • sugar maple
  • shagbark hickory
  • bitternut hickory
  • bur oak
  • mockernut hickory

Tree species likely to do poorly with climate change:

  • eastern hemlock
  • pin oak
  • black willow
  • bigtooth aspen
  • American basswood
  • sassafras
  • yellow birch
  • slippery elm
  • eastern cottonwood
  • swamp white oak
  • American hornbeam
  • black ash
  • cucumbertree
  • serviceberry
  • shingle oak
  • flowering dogwood
  • honeylocust
  • scarlet oak
  • black maple
  • shellbark hickory
  • chinkapin oak
  • red mulberry
  • eastern redbud
  • eastern white pine
  • sweet birch
  • sweetgum
  • Ohio buckeye
  • balsam fir
  • swamp chestnut oak
  • striped maple
  • gray birch
  • red pine
  • pin cherry
  • white spruce
  • pawpaw
  • yellow buckeye

Tree species likely to move into the region within 100 years:

  • eastern redcedar
  • common persimmon
  • loblolly pine
  • southern red oak
  • shortleaf pine
  • post oak
  • winged elm

More information about climate change and trees

Study credits

  • U.S. Forest Service Northern Research Station, Landscape Change Research Group: Louis Iverson, Anantha Prasad, Matt Peters, Steve Matthews
  • Northern Institute of Applied Climate Science: Patricia Leopold

Plant hardiness zones change maps

Heat zones change maps

Tree species tables for large watersheds

Tree species tables for 1x1 degree grids

Annual precipitation change maps

Tree species table for entire LEAP region

Tree species tables for small watersheds

Tree species tables for subregions

Mean annual temperature change maps