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Abstract
This field note presents an early example of a forest climate adaptation tree planting
project incorporating assisted migration in southern New England which is valuable
in providing lessons that can inform future work in this region and elsewhere. This
effort is notable for moving forward through the implementation and monitoring
stages during a period when many similar projects encountered barriers. The project
is located on watershed protection forestland owned by the Providence Water Supply
Board, a public utility in Rhode Island. Using a suite of tools developed through
the Climate Change Response Framework, watershed forest managers carried out a
“transition” strategy climate adaptation planting in 2015, seeking to improve regeneration
in an area of forest near the state’s main drinking water reservoir. Seedlings
of both native and assisted migration tree species projected to be adapted to future
climate conditions were planted in adjacent areas that had experienced oak regeneration
failure. Half of the seedlings of each species were planted within a deer
exclosure fence and half were planted in an unfenced area. Annual monitoring has
allowed for comparison of survival and growth of a subset of planted trees at these
two sites for 10 growing seasons. Deer herbivory is believed to be the most significant
factor contributing to differences in tree survival rates between the fenced and
unfenced areas. Both native and non-native species have been able to survive when
protected from deer browse, while differences are inconclusive after nearly a decade.
This informal experimental planting provides a case study illustrating some of the
opportunities and challenges associated with implementing assisted migration in a
non-research, operational-scale setting.