Approach
EASTERN: Long-term ecosystem function may be jeopardized if existing and newly migrated species fail to regenerate and establish. Active management of understory regeneration may help transition forests to new and better-adapted compositions more quickly by promoting desired species and reducing competition from undesirable, poorly adapted, or invasive species. Natural disturbances often initiate increased seedling development and genetic mixing, and can be used to facilitate adaptation. Silvicultural prescriptions can mimic natural disturbance to promote regeneration in the absence of natural disturbance. Under drier conditions and increased stress, promoting regeneration and discouraging competitors may require more-intensive site preparation, including prescribed fire, soil disturbance, and herbicide use. When forests are dominated by one or a few species, this approach may lead to conversion to a different forest type.
WESTERN: Long-term ecosystem function may be jeopardized if existing and newly migrated species fail to regenerate and establish. Active management of understory regeneration may help transition forests to new and better-adapted compositions more quickly by promoting desired species and reducing competition from shrubs or from undesirable, poorly adapted, or invasive species. Natural disturbances often initiate increased seedling development and genetic mixing and can be used to facilitate adaptation. Silvicultural prescriptions can mimic natural disturbance to promote regeneration in the absence of natural disturbance. Under drier conditions and increased stress, promoting regeneration and discouraging competitors may require more intensive site preparation, including prescribed fire, soil disturbance, and herbicide use. When forests are dominated by one or a few species, this approach may lead to conversion to a different forest type.
Tactics
- Preventing & removing undesired species, including invasive nonnative, aggressive native species, or shade tolerant species where overly abundant due to fire suppression tactics, in order to reduce competition for moisture, nutrients, and light.
- Controlling beech suckers, sprouts, and brush by using herbicide or mechanical treatment in areas affected by beech bark disease in order to reduce competition with the regeneration of other species.
- Planting or seeding sufficient stocks of desired species before undesirable species have the chance to establish or compete.
- Performing timber stand improvement to favor and promote the growth of desirable growing stock.
- Planting in heterogeneous patches to mimic historic stand structures to favor future diverse understory species.
- Thinning stands to favor and promote the growth of desirable species (e.g., shade-intolerant pines and oaks).
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. 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