Reforestation following megafires in boreal forests: silvicultural challenges and available tools.

In North America, climate change is projected to increase wildfire activity, leading to more frequent megafires that will likely overwhelm current regeneration processes, threatening the resilience of boreal forests and the services that they provide. The devastating 2023 wildfire season exposes the magnitude of the challenge facing North America, including eastern regions. Post-fire reforestation needs can far exceed current capacity, which relies almost exclusively on manual tree planting. Our review addresses urgent needs to increase reforestation capacity to restore vast burned landscapes that are experiencing regeneration failures. We first provide an overview of current challenges and promising reforestation methods for tree planting and direct seeding. Challenges include addressing regeneration failure risks and limited road access, and strengthening reforestation value chains amid workforce shortages. We discuss the suitability of traditional and innovative reforestation methods, considering these challenges, to situate them within a broader restoration strategy. We show that using multiple methods expands reforestation capacity by providing more options for reforesting sites with a wider range of biophysical conditions. However, robust evidence on method-specific outcomes across different timescales is still needed to understand their effectiveness for post-fire restoration. Future research should further assess the cost-benefits of these methods and improve our ability to predict and mitigate regeneration failures across varying forest landscapes to support efficient restoration efforts. Our work provides a foundation for transferring current knowledge into strategic reforestation planning and execution. It is relevant to communities, scientists, governments and managers seeking to adapt regeneration silviculture to changing fire regimes.