Approach
EASTERN: Repeated periods of warming and cooling over the last 15,000 years have resulted in large shifts in species composition. Novel combinations of climatic and site conditions are expected to continue to affect individual species in different ways. Although some species may not occur in a forest or community type as currently defined, they may have been together previously. Novel mixing of native species may lead to the dissolution of traditional community relationships and result in conversion to a newly defined or redefined forest or community type. (1) WESTERN: Repeated periods of warming and cooling over the last 15,000 years have resulted in large shifts in species composition. Novel combinations of climatic and site conditions are expected to continue to affect individual species in different ways. Although some species may not occur in a forest or other community type as currently defined, they may have been together previously. Novel mixing of native species may lead to the dissolution of traditional community relationships and result in conversion to a newly defined or redefined forest or other community type. (2)
Tactics
- Planting or seeding a mixture of native species currently found in the area that are not typically grown together but may be a suitable combination under future conditions.
- Underplanting with eastern white pine to diversify the conifer component of a stand that has had no eastern white pine.
- Intensifying site preparation in a northern hardwoods stand to promote the establishment of oak from an adjacent stand.
- Allowing a species native to the region (e.g., black locust) to establish where it was not historically present, if it is already encroaching and likely to do well there under future climate conditions.
- Underplanting with shade tolerant species (which tend to have wide ecological tolerance) to diversify the conifer component of a stand.
- Allowing a species native to the region or elevational zone to establish where it was not historically present, if it is already encroaching and likely to do well there under future climate conditions.
Strategy
Strategy Text
Species composition in many forest ecosystems is expected to change as species adapt to a new climate and transition into new communities (Iverson et al. 2004b). This strategy seeks to maintain overall ecosystem function and health by gradually enabling and assisting adaptive transitions of species and communities in suitable locations. This may result in slightly different species assemblages than those present in the current community, or an altogether different community in future decades. This strategy includes aggressive actions to promote ecosystem change rather than an unchanging community or species mix. Many of the approaches in this strategy attempt to mimic natural processes, but may currently be considered unconventional management responses. In particular, some approaches incorporate assisted migration, which remains a challenging and contentious issue. It is not suggested that managers attempt to introduce new species without thoroughly investigating potential consequences to the native ecosystem. This approach is best implemented with great caution, incorporating due consideration of the uncertainties inherent in climate change, the sparse record of previous examples, and continued uncertainties of forest response. Outcomes from early efforts to transition communities can be evaluated to provide both information on future opportunities and specific information related to methods and timing.
1. Swanston, C.W.; Janowiak, M.K.; Brandt, L.A.; Butler, P.R.; Handler, S.D.; Shannon, P.D.; Derby Lewis, A.; Hall, K.; Fahey, R.T.; Scott, L.; Kerber, A.; Miesbauer, J.W.; Darling, L.; 2016. Forest Adaptation Resources: climate change tools and approaches for land managers, 2nd ed. US Department of Agriculture, Forest Service, Northern Research Station. 161 p. http://dx.doi.org/10.2737/NRS-GTR-87-2,