Managing Forests under Climate Change
Climate change is predicted to significantly affect our forests, and therefore our landscape and our society.
The resiliency of our forests depends on site conditions, interactions among plants and animals, the amount of forest, and historical and current human pressures. It also depends on genetic fitness and diversity. Our forests are diverse in species, but each species is also made up of unique, locally adapted populations and individuals. So any plan to adapt to climate change must consider these complex factors in any local area.
As the climate changes, some individual trees or even whole local populations of a species may not prove adapted, nor have the capacity or time to evolve. And they may not be able to migrate to more favourable conditions – there is evidence that the climate is changing faster than natural migration, via wind, water and animals, has occurred in the past. Another barrier to migration is the effect that temperature and other weather extremes could have on flowering and seed production.
So our forests’ capacity to adapt, thrive and provide the many benefits our society needs, depends on the quality of today’s efforts – our ability to conserve, manage and restore our forests as outlined below. We will also depend on our neighbours’ success – forests in northern USA may contain options for southern Ontario’s future forests – both southern populations of our native species and species new to us. Likewise our northern neighbours will rely on our forests.
Read more to understand how climate change is already having an effect on our forest: Climate Change and Ontario Forests – (PDF 18 kB)
Conserve Forests Strategically within local landscapes
- To conserve diversity within species = the many unique local populations and individuals
- To maximize habitat for all species
- To conserve soil and local water systems
- To facilitate natural migration processes
- To maintain local climate moderation function
Restore Forests Strategically
- Focus on restoring the site conditions that will support future forests
- Focus on connecting fragmented forests to support natural migration = “assisting migration”
- Use high quality seed from genetically fit sources (see Woody Plant Seed Collection Guidelines for a Changing Climate)
- Move southern sources north = assisted migration, where site conditions allow, possibly in a mix with local sources. (The Role of Assisted Migration in Southern Ontario)
- Develop afforestation competencies to ensure the success of plantings
Bank seed off-site (ex situ)
- Collect and bank source-identified seed of species that can be stored long term (orthodox)
- Plant seed of other species outside of their origin = assisted migration, to become seed production areas for future climates
Monitor natural forests and assisted migration plantings
- To learn more about species’ basic biology and determine their vulnerabilities and strengths
- To observe climate change effects on different species, sites and ecosystems
- To communicate the results to local landowners and forest managers
Climate Change Resources

- Natural Resources Canada’s Forestry Adaptation Toolkit
- Forest Vulnerability Assessment Tool for Drought and Migration Failure of 22 Canadian tree species
- Ontario Centre for Climate Impacts and Adaptation Resources
Synoposis of Ontario Government’s forest research including climate change- Sign up for the Forestry Adaptation Community of Practice for webinars, research papers and news
- US Climate Change Tree Atlas