Credit: Vlada Karpovich from Pexels
Native trees in the Pacific Northwest are dying off due to climate changes, and the U.S. Forest Service, Portland, Oregon, and citizen groups around Puget Sound are implementing a strategy called “assisted migration” to help save them.
As the world’s climate warms, tree growing ranges in the Northern Hemisphere are predicted to move farther north and higher in elevation.
Though trees can’t move themselves, humans can help them keep up with climate change by moving them to more favorable ecosystems using an approach known as assisted migration.
However, not everyone agrees on what type of assisted migration the region needs—or if it’s always beneficial.
In the Pacific Northwest, there is a divide between groups advocating for assisted migration to help struggling native trees, and those concerned about native species being replaced by trees from the south.
“There is a huge difference between assisted population migration and assisted species migration,” said Michael Case, a forest ecologist at the Virginia-based Nature Conservancy.
Case currently runs an assisted population migration experiment at the Conservancy’s Ellsworth Creek Preserve in western Washington.
Assisted population migration involves moving a native species’ seeds and genes within its current growing range, which has fewer ecological risks than introducing a species from outside its range.
A third form of assisted migration, called “range expansion,” moves a species just beyond its current growing range.
The Forest Service is currently pursuing assisted population migration because it’s likely to have few, if any, “negative consequences” to ecosystems, according to Dr. David Lytle, the agency’s deputy chief for research and development.
This work is vital to help the forests adapt to climate change, and its effectiveness is being closely monitored and studied.
To learn more about this important efforts, please click on the link below.
