How well does tree planting work in climate change fight? It depends
- January 30, 2025
- 720 comments
- Alex Fiske
An international research collaboration, including experts from Oregon State University (OSU), has unveiled a nuanced understanding of tree planting as a strategy for combating climate change. The study, led by Conservation International and published in Nature Climate Change, synthesizes data from thousands of reforestation sites across 130 countries, revealing that the effectiveness of tree planting is highly context-dependent.
Key Insights from the Tree Planting Research
Jacob Bukoski, a researcher at OSU's College of Forestry, highlighted that while trees are widely recognized for their ability to sequester carbon dioxide, the approach to forest expansion requires careful consideration. The research identifies two primary methods for increasing forest cover: natural regeneration and active planting.
Natural regeneration is generally slower and less costly, while planting accelerates growth but incurs higher expenses. The findings indicate that natural regeneration is the most cost-effective method for approximately 46% of the areas studied, while tree planting is preferable for about 54%. Notably, a combined approach of both methods is projected to be 44% more effective than relying solely on natural regeneration and 39% more effective than exclusive tree planting.
Regional Variations in Tree Planting Effectiveness
The research provides valuable insights into specific regions where each method may be more advantageous. Natural regeneration is particularly effective in:
- Western Mexico
- The Andean region
- Parts of South America
- West and Central Africa
- India
- Southern China
- Malaysia
- Indonesia
Conversely, tree plantations are more suitable in:
- The Caribbean
- Central America
- Brazil
- Northern China
- Southeast Asia
- The Philippines
- Various regions in Africa
Bukoski noted that the choice between natural regeneration and planting is influenced by several factors, including opportunity costs, carbon accumulation rates, harvest rates, and implementation costs. This nuanced understanding underscores the need for tailored approaches to reforestation based on local conditions.
Broader Implications for Climate Action
The authors of the study stress that while reforestation can play a significant role in mitigating climate change, it should complement, rather than replace, efforts to reduce fossil fuel emissions. They estimate that the total potential carbon sequestration from reforestation over a 30-year period would equate to less than eight months of global greenhouse gas emissions, highlighting the limited scope of reforestation alone in addressing the climate crisis.
Moreover, the researchers advocate for a broader perspective on the benefits of tree planting beyond carbon sequestration. Factors such as biodiversity, local livelihoods, demand for wood products, and non-carbon biophysical effects should also be considered when planning reforestation efforts.
Conclusion
This comprehensive study sheds light on the complexities of using tree planting as a climate change mitigation strategy. By revealing that a combination of natural regeneration and active planting may yield the best results, the research encourages policymakers and conservationists to adopt more nuanced approaches to forest management. The findings offer a promising outlook for enhancing the effectiveness of reforestation initiatives, ultimately contributing to global efforts to combat climate change.
For more updates and in-depth news on the latest in forestry, visit forestry.com/editorial/.
Hi Jacob - My main concern is choice of species varieties that will survive now and also under likely future climate. Must be site specific to be useful -- "when you've seen one site...you've seen one site". Thanks.
Phil Sollins
February 3, 2025