By Lindsay Seventko, American Forests

Forests have been migrating and evolving throughout planet earth’s history. For example, up until 4,000 years after the last Ice Age, spruce trees were a rare species not typically found in what we now consider boreal forests. Although the gradual movement and continual change of forests have characterized the earth’s past, climate change threatens to force migration faster than forests can catch up.

In the face of up to 37 percent loss of Earth’s plant and animal species expected by 2050, the issue of traditional habitats not being able to survive in the areas that they have for the past few thousand years has raised some unprecedented forest conservation questions — should forest managers assist the migration of forests to help them better withstand climate change in the long run, instead of trying to hold on to “native” species as much? To some conservationists, failure to help forests migrate may just delay the inevitable — mass extinctions of the species that aren’t able to move fast enough. Here’s the dilemma facing officials in three iconic National Parks.

Sequoia National Park

Redwoods
Credit: Yinghai Lu

California’s giant sequoias have been protected as one of America’s most treasured and impressive landscapes, but forest managers may have to decide within the next 10 years whether or not these giants will be able to withstand the effects of climate change. As snowpack declines and temperatures rise, the trees may be weakened and, thus, be more susceptible to invasive insects that have previously never threatened the giants. The conversation now becomes focused on the question ofshould the park service focus on preserving this iconic ecosystem in the Southern Cascades, where it may be better suited to withstand climate change for the next thousand years?

Joshua Tree National Park

Joshua Trees
Credit: Angel La Canafora via Flickr.

When thinking about the species most affected by climate change, typically polar bears or penguins come to mind. However, even desert ecosystems are at risk of extinction. The Joshua Tree, found in the unique forest along the edge of the Mojave Desert simply isn’t reproducing in many traditional areas anymore, raising concern that without assisted migration (perhaps north to the Great Basin), the entire forest ecosystem will be lost — including the pinyon pines and the yucca moth which depends on the Joshua Tree, and which each yucca plant relies on in turn.1

Glacier National Park

Glacier National Park
Credit: Rex Brown via Flickr.

In Glacier National Park, the effects of climate change are having the reverse effect on forests than one would expect — it will actually increase forest cover. So why is this bad news?

The number of ice flows found within the park have already decreased from 150, historically, to now less than 30 and are expected to be nonexistent within 30 years. Without this ice, rare alpine gardens will slowly disappear as forests grow higher and higher on the mountains, threatening the plants and wildlife that rely on the meadow-like conditions. Wolverines, which had only begun to make a comeback after being trapped to near extinction, may disappear completely without the deep snow to build their dens in.

Davidson, Osha Gray. “Climate Change Threatens an Iconic Desert Tree” National Geographic: October 28, 2015.

Than, Ker. “How Climate Change Will Transform the National Parks’ Iconic Animals and Plants.” Smithsonian: August 8, 2016.

Wines, Michael. “Climate Change Threatens to Strip the Identity of Glacier National Park.” New York Times: November 22, 2014.