Can reforestation really solve climate change?

Maia Welbel

Here at Farm, we are all about land-based climate action. How can we engage with the Great Plains region and beyond to mitigate environmental degradation and climate change? These strategies can take on many forms — from clean energy, to water conservation, to local food.

One strategy that has gained significant interest over the past couple of decades is wide-scale reforestation. We’re talking hundreds of billions of trees over billions of acres of land.

In some eco-regions, forests are a significant carbon sink. This means they capture and store carbon dioxide molecules from the atmosphere so they are no longer floating around trapping heat. In a forest, atmospheric carbon is absorbed via photosynthesis into biomass (leaves, roots, trunks, branches), dead organic matter, and surrounding soil.

Unfortunately, mass deforestation — losses totaling about a billion acres since 1990 per the Food and Agriculture Organization (FAO) — has meant huge volumes of CO2 released into the atmosphere, and opportunities for reabsorption literally razed to the ground.

Could re-building forests stave off climate catastrophe?

In short, it’s complicated. The forests that capture the most carbon on Earth are thousands of years old and encompass complex ecosystems of plants, animals, insects, and fungi, uniquely suited for their specific climate and landscape.

Many established forests, especially in tropical climates, have diminished or lost capacity for carbon storage due to human-imposed degradation and increased intensity of forest fires.

Suffice it to say, lining up a few thousand identical seedlings in rows and waiting for them to grow will not save us.

How to mindfully use reforestation as an approach to carbon capture?

A 2019 study looked at five wildlife reserves in peninsular India and showed that “promoting natural forest regeneration and/or multi-species native tree plantations instead of plantation monocultures could benefit climate change mitigation efforts, while offering valuable co-benefits for biodiversity conservation and other ecosystem services.” While mono-dominant plantations (man-made forests comprised of mostly a single tree species) neared the carbon capture and storage potential of natural forests, their instability in the face of increasing droughts, pests, and other climate disturbances made them unreliable as a long term climate mitigation strategy. Basically, the restoration of native species ecosystems, while more resource-, time-, and knowledge-intensive, is ultimately a much more secure way to keep CO2 out of the atmosphere.

The International Union for Conservation of Nature (IUCN), which supports a number of forest landscape restoration projects globally, emphasizes resilient design so reforested areas can adapt to fluctuations in climate and other environmental factors. IUCN also works to restore the social and economic functions of forestland, recognizing the range of ecosystem goods and services that benefit surrounding communities. The flexibility of a conservation, recovery, and sustainable management approach to forest restoration, as opposed to new monoculture planting, is also key in adapting to evolving societal needs.

Trillion Trees, a coalition of BirdLife International, Wildlife Conservation Society, and World Wildlife Fund, directs funds and supports research into forest protection and restoration, and advocates for policy that prioritizes forests around the world. The organization commits to long-term stewardship at each forest site to build trusting relationships with local communities and work with them to develop appropriate forest restoration solutions. The attention to local context and planning for sustained vitality rather than short-term outcomes is what makes this initiative part of a viable climate strategy.

Terraformation, a technology company committed to scaling natural carbon capture, works to restore complex native forest ecosystems using site-specific, community-led, and long-term strategies. Their diverse seed library, compact nursery systems, and solar-powered desalinization design help teams regenerate carbon-rich forests around the globe.

Pachama, a technology company is focused on leveraging data, artificial intelligence, and automation to protect ecosystems, restore forests, and improve carbon markets. They have  already protected over 1,000,000 hectares of forest in 15 countries through 39 projects.

According to a 2016 study on “Seed Production Areas for the Global Restoration Challenge,” the current and future demand for seeds far exceeds the volume that can be practically, economically, and ethically sourced from the wild. Responding to this issue, The Global Assessment of Forest Genetic Resources adopted by the FAO in June 2013 asked policymakers to reinforce national seed programs to provide genetically appropriate seeds for plantations and restoration in sufficient quantities.

What are the challenges limiting forest restoration?

Terraformation cites seed shortages as one of the largest bottlenecks to ecosystem restoration success — “Resilient restoration relies on species diversity, which starts with collecting and storing seed from a range of species.” The choice of seeds collected at the start of a restoration project can determine plant survival rates years in the future.

Preserving seeds properly is also crucial to reforestation, and requires specialized equipment and expertise. According to Terraformation, “without temperature-regulated storage conditions, many seeds lose viability within one year of collection.”

Yet another constraint, one which is less amenable to technical solutions, is the dwindling number of skilled seed collectors in the U.S. Seed collecting is an extremely sophisticated job — it requires extensive botanical knowledge, athletic ability (many seed collectors literally climb trees to retrieve them), understanding of sustainable collection practices (i.e. not harvesting more than is good for the health of the tree), mastery of seasonal fluctuations (the abundance of the seeds varies by year), and more. Much of this wisdom is passed from mentor to student, making it hard to scale a workforce to the extent required.

Even with the best intentions, expertise, and technology, reforestation will not succeed as an impactful climate mitigation strategy without supportive public policy. Governments will need to back up training, land access, and sustainability efforts.

Like most restoration efforts we talk about at Farm, reforestation is a potentially effective, but non-exhaustive tool for addressing climate change. When approached holistically, with  insistence on human and environmental sovereignty, it can play a powerful role.