
Moriarty Science Seminar: Northward Migration of Umbrella Magnolia via Horticultural Escape
May 3, 2021, 12:00 pm - 1:00 pm
Online
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R.W. Moriarty Science Seminar Presents: Northward Migration of Umbrella Magnolia via Horticultural Escape
Speaker: Jesse Bellemare
Due to climate change, many species will need to shift their distributions northward in coming decades; however, slow rates of natural dispersal might be insufficient to keep pace with the high rate of change, resulting in species declines or extinctions. To avoid this outcome, some biologists have proposed human intervention via “assisted migration” to move species northward into regions where they have not lived in the past, but where they are expected to survive in the future. Significant concerns about the potential for invasive behavior have delayed implementation of this controversial strategy, but native plant horticulture might already be resulting in “accidental” assisted migration for some plant species. This talk will review the case of Umbrella Magnolia (M. tripetala), an understory tree species native to southern Pennsylvania and areas southward that has historically been planted north of its native range in the Northeast U.S. With recent climate change, this tree has begun to escape from horticulture and naturalize north of its native range, effectively shifting its range northward in the directions forecast by climate models. The species provides a striking example of human-assisted migration and raises challenging questions about our definitions of “native” in a world of increasing species range shifts due to climate change.