Forest Service Moving Trees to Save Them
2024-01-05
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1Some important tree species native to the northwestern states in the U.S. are no longer growing well because of climate change.
2As conditions change in states such as Washington, Oregon and California, trees such as the Douglas fir, Western red cedar, giant sequoia and redwood may need to move -- with the help of humans.
3Some of the trees do not do well when temperatures rise. Others suffer during times of drought.
4The goal is to move the trees to areas where the climate might more suitable.
5Forest scientists are generally in favor of moving the trees so they do not die out.
6However, not all of the scientists agree on the best way to do it.
7There are three ways to move trees: assisted population migration, assisted species migration and range expansion.
8Assisted population migration involves scientists moving a tree's seeds within its current growing range.
9Assisted species migration involves scientists moving a species far from its existing area.
10In this case, that would include moving redwoods and sequoias from California to Washington.
11The third way, range expansion, moves trees just outside their current growing range.
12Each way has different results for the trees and other animals and insects that depend on the trees.
13Michael Case is a forest ecologist at the Nature Conservancy in Virginia.
14He said "there is a huge difference" among the different migration methods.
15He said the risk of failure increases "whenever you plant something in an area where it is not locally found."
16He said the risk is not only to the trees. There is also the risk of causing problems in the ecosystem.
17Case is working on an assisted population migration program with Douglas fir and Western hemlock trees.
18He is testing whether the trees, originally from drier parts of the northwest, can do well in western Washington where there is a drought.
19His organization believes that assisted population migration has fewer risks.
20The U.S. Forest Service also takes part in assisted population migration programs.
21Dr. David Lytle is the agency's deputy chief for research and development.
22He said the agency is "very very cautious" about moving plants outside of their "historic range."
23Douglas Tallamy is a professor of entomology and wildlife ecology at the University of Delaware.
24He said one worry about species migration is that local caterpillars might not eat the leaves of trees that are new to the area.
25The caterpillars serve as food for birds and other animals, so they must have a good food source.
26Although the concerns are documented, the city of Portland, Oregon, is working on a species migration project for 11 tree species.
27The project includes three oak trees: California black oak, canyon live oak and interior live oak.
28Tallamy said oak trees are among the most important in North America.
29"When you move them out of range," he said, "the things that are adapted to eating them no longer have access to them."
30The city responded to questions from the Associated Press, and said it is using guidelines "from universities, state and federal sources" and more, in its project.
31Another group working on species migration projects in the northwest is called PropagationNation.
32To propagate means to produce a new plant through the use of seeds or parts of another plant.
33That organization is planting non-local trees around the Seattle, Washington area in hopes that they will start growing in places where Western red cedar, Western hemlock and big leaf maple are having trouble.
34David Milarch is the leader of a group in Michigan that supports keeping old trees alive.
35It is called Archangel Ancient Tree Archive.
36Milarch said the hope is to permit redwoods and sequoias to grow in areas to the north.
37The hope is not to replace native trees.
38He said his group hopes the trees "will still be here in 100 to 200 years and not join the list of trees that are going extinct."
39The organizations that are not practicing widely accepted methods for moving species feel like the risks are worth it.
40But Robert Slesak is not sure about either practice.
41He oversees population migration sites run by the U.S. Forest Service in California, Oregon and Washington.
42He said he has concerns about assisted species migrations and assisted population migrations that lack experimental rigor.
43Rigor describes an activity that has been tested with high standards.
44He said all of the ideas about how to move trees should follow experiments that have already produced strong results.
45"Everyone knows we need to do some kind of action related to climate, but there's a real risk of making it worse."
46I'm Dan Friedell.
1Some important tree species native to the northwestern states in the U.S. are no longer growing well because of climate change. 2As conditions change in states such as Washington, Oregon and California, trees such as the Douglas fir, Western red cedar, giant sequoia and redwood may need to move -- with the help of humans. 3Some of the trees do not do well when temperatures rise. Others suffer during times of drought. The goal is to move the trees to areas where the climate might more suitable. 4Forest scientists are generally in favor of moving the trees so they do not die out. However, not all of the scientists agree on the best way to do it. 5There are three ways to move trees: assisted population migration, assisted species migration and range expansion. 6Assisted population migration involves scientists moving a tree's seeds within its current growing range. Assisted species migration involves scientists moving a species far from its existing area. In this case, that would include moving redwoods and sequoias from California to Washington. 7The third way, range expansion, moves trees just outside their current growing range. Each way has different results for the trees and other animals and insects that depend on the trees. 8Michael Case is a forest ecologist at the Nature Conservancy in Virginia. He said "there is a huge difference" among the different migration methods. 9He said the risk of failure increases "whenever you plant something in an area where it is not locally found." He said the risk is not only to the trees. There is also the risk of causing problems in the ecosystem. 10Case is working on an assisted population migration program with Douglas fir and Western hemlock trees. He is testing whether the trees, originally from drier parts of the northwest, can do well in western Washington where there is a drought. His organization believes that assisted population migration has fewer risks. 11The U.S. Forest Service also takes part in assisted population migration programs. Dr. David Lytle is the agency's deputy chief for research and development. He said the agency is "very very cautious" about moving plants outside of their "historic range." 12Douglas Tallamy is a professor of entomology and wildlife ecology at the University of Delaware. He said one worry about species migration is that local caterpillars might not eat the leaves of trees that are new to the area. The caterpillars serve as food for birds and other animals, so they must have a good food source. 13Although the concerns are documented, the city of Portland, Oregon, is working on a species migration project for 11 tree species. The project includes three oak trees: California black oak, canyon live oak and interior live oak. Tallamy said oak trees are among the most important in North America. "When you move them out of range," he said, "the things that are adapted to eating them no longer have access to them." 14The city responded to questions from the Associated Press, and said it is using guidelines "from universities, state and federal sources" and more, in its project. 15Another group working on species migration projects in the northwest is called PropagationNation. To propagate means to produce a new plant through the use of seeds or parts of another plant. 16That organization is planting non-local trees around the Seattle, Washington area in hopes that they will start growing in places where Western red cedar, Western hemlock and big leaf maple are having trouble. 17David Milarch is the leader of a group in Michigan that supports keeping old trees alive. It is called Archangel Ancient Tree Archive. Milarch said the hope is to permit redwoods and sequoias to grow in areas to the north. The hope is not to replace native trees. 18He said his group hopes the trees "will still be here in 100 to 200 years and not join the list of trees that are going extinct." 19The organizations that are not practicing widely accepted methods for moving species feel like the risks are worth it. 20But Robert Slesak is not sure about either practice. He oversees population migration sites run by the U.S. Forest Service in California, Oregon and Washington. 21He said he has concerns about assisted species migrations and assisted population migrations that lack experimental rigor. Rigor describes an activity that has been tested with high standards. 22He said all of the ideas about how to move trees should follow experiments that have already produced strong results. 23"Everyone knows we need to do some kind of action related to climate, but there's a real risk of making it worse." 24I'm Dan Friedell. 25Dan Friedell adapted this story for Learning English based on a report by the Associated Press. 26_________________________________________________ 27Words in This Story 28drought -n. a dry weather period 29suitable -adj. comfortable or correct 30migration -n. the movement of something to a new place 31range -n. the usual area of land covered by a plant or tree (in this case) 32ecologist -n. a person who studies living things and their environment 33locally -adj. a small area where something is originally found 34cautious -adj. careful or concerned 35adapted -adj. something that has changed and now functions in a new place 36respond -v. to answer 37replace -v. to put something new in place of something 38to go extinct -v. to die out 39rigor -n. the quality of being exact, careful or strict