Adapting to a Changing Climate: A Report for Southern Region Sustainable Forest License Holders

In 2017, the Forest Gene Conservation Association (FGCA) undertook an impact assessment for the four Sustainable Forest License (SFL) holders and the Algonquin Forest Authority who operate within the Great Lakes–St. Lawrence forest in the southern crown forest region. Climate change is posing a unique challenge to forest managers. The lifespan of trees in the temperate hardwood forest can be several centuries in length and rotation ages for managed forests is often over 100 years. Climate change is almost certainly affecting forest growth rates, the distribution and associations of tree species, synchronicity of ecosystem processes and the ability to carry out forest operations. The report is based on an extensive review of the literature and provides research findings, information on other jurisdictions’ response to the challenge, and recommended reading. Using species distribution modeling (SDMs), under future scenarios many species face southern range contraction faster than northern edges can expand. However, species such as white pine and red maple, in the middle of their range in Ontario, could perform slightly better over the next century. Simultaneously, southern populations of boreal species like jack pine and black spruce will face challenges. Along with providing tree species climate envelope projections and seed zone climate projections, this report provides a set of recommendations for forest managers and is designed as a reference document that will be updated regularly. As the past will no longer be the best guide for forest stand development, forest practitioners will have to bring considerations of climate change adaptation into routine planning and operations. Above all, a clear understanding of forest genetic resource management principles is necessary. A companion document – Applying Forest Genetic Resource Management Principles in the Great Lakes–St. Lawrence Forest (Appendix F of this report) –will help ensure adaptive management proposals conserve genetic diversity, the foundation of future forest resilience, no matter the threat.

Understanding and Assessing Impacts

This project was undertaken following interviews with SLFs conducted by the Forest Gene Conservation Association in 2016. Although awareness and concern about climate change was high, the staff of these forest management companies were not confident about how to address the problem. Climate change is almost certain to affect forest growth rates, the distribution and associations of tree species, synchronicity of ecosystem processes and the ability to carry out forest operations. The unprecedented outbreak of the mountain pine beetle in western Canada is but one example of a climate-induced change that can have profound impacts on the forest and how it is managed. More subtle effects are also being observed across Canada. For example, the length of the growing season is increasing, bud burst in sugar maple is occurring earlier, the flowering period of aspen is occurring earlier, forest birds are arriving back on territory out of sync with insect hatching, and tree lines are moving upward in elevation. The report presents climate envelope projections for Ecoregion 5E obtained from Ontario Climate Change web tool. Climate envelope projections and maps for Ontario’s Seed Zones 28-31, 35, 36 were also developed based on a group of climate variables to show where the climate of these zones is moving in the future. The report identifies a series of climate change impacts, both positive and negative, on forest stands, forest landscapes and the forestry sector grouped under the following categories: precipitation, temperature, biological stressors, disturbance, genetics, and forest management and economy.

Identifying Actions

The report presents a series of climate change adaptation principles for SFL holders to consider and makes a series of recommendations to SFL holders. The recommendations include:

  • Conduct a vulernability assessment for operations, policies, and programs; conduct vulnerability assessments at a forest management unit scale to highlight in finer detail the specific sites, species, and systems that may be at risk and allow more targeted adaptation strategies to be formed
  • Contribute to the Seed Collection Area Network to help move the forestry sector in Southern Ontario toward a more rigorous systems of documenting where nursery stock originates.
  • Re-invest in a renewed and cooperative seed banking stragegy to help address vulnerable species, populations and allow for greater fledibility in future response.
  • Undertake seed and stock movement operational trials, such as assisted migration and assisted range expansion
  • Modify silvicultural practices
  • Consider future climate scenarios when planning, constructing, and installing infrastructure such as culverts and bridges
  • Consider development of carbon offset opportunities
  • Prepare for reduction in winter harvest
  • Improve communication of the role of SFLs and forest management in mitigating climate change
  • Consider participating in programs to conserve energy and track progress towards reducing greenhouse gas emissions from operations


This report has been circulated widely and used by SFLs beyond the initial group of SFLs involved in this project. Each SFL uses the information differently. Some have incorporated concepts into their long-term forest managent plans. Others have continued working with the FGCA on more detailed planning for their forests as well as setting up assisted population migration planting trials for monitoring and future seed sources.

Outcomes and Monitoring Progress

The report makes recommendations for SFLs for future monitoring, including:

  • Conducting wood supply monitoring with climate change scenarios
  • Examining whether existing monitoring program will be adequate for their needs given the character and magnitude of climate change projected for this region

The report emphasizes the need to increase forest monitoring as critical components of sustainable forest management in the next 50–100 years until more is reported about species-specific range shifts or biological responses.

Next Steps

FGCA continues to work with SFLs to undertake vulnerability assessments, provide strategic forest management advice, and facilitate assisted migration to support the resiliency of our forests.


Using climate change projections enables better adaptation decisions, as it allows you to better understand how the climate may change. To learn how to choose, access, and understand climate data, visit’s Learning Zone.
For more information on variables that may be useful in work related to Forestry/Urban Forestry, visit and click “Explore by Variable”. Here you will find pertinent future climate projections related to:

  1. Maximum temperature
  2. Maximum number of consecutive dry days
  3. Number of periods with more than 5 consecutive dry days
  4. Standardized precipitation evapotranspiration index (3-months)