by Elizabeth Matteri, Masters in Marine Affairs Candidate 2021, University of Washington School of Marine and Environmental Affairs
I was tasked with exploring research on the co-benefits and costs of two forest Natural Climate Solutions (NCS) pathways: deferred timber harvest (DTH) and replanting after wildfire.
Washington State’s coastal Doug Fir forests have some of the greatest carbon storage abilities of any forests in the world, so at first glance, DTH shows a lot of potential. Most timber rotations here in Washington are around 30-40 years long, and by deferring those harvests to 70-80 years and beyond, more carbon can be captured by the growing trees—in other words, removed from the atmosphere.
My second pathway focused on the carbon that could be stored by replanting after wildfires so that the growing vegetation and trees can also sequester carbon from the atmosphere. As an Oregon native, and after yet another devastating fire season, this pathway hit particularly close to home.
Deferred Timber Harvest
Studies show that out of the pathways that TNC had us review, it has the greatest carbon sequestration potential. In addition, there are a number of different co-benefits associated with extending harvest rotations.
Longer rotations allow time for trees to mature, and for stand and canopy structure to change and become more complex, supporting a greater variety of flora and fauna. These changes create habitat for wildlife and promote biodiversity, and certain species (including endangered species like the Northern Spotted Owl) thrive in older timber stands.
Water and soil quality can also improve with longer rotations.
Economically, older stands lead to both greater quantities and higher quality of wood when harvest finally occurs.
However, DTH activities would have a disproportionately negative impact on communities that depend on the timber industry—as extended rotations lead to an immediate short-term revenue loss.
Other considerations include leakage: if timber rotations are extended in one area, the timber industry might simply move their operations to a different area where cutting on shorter rotations can continue. Lastly, while certain species thrive in older forests, other species require early seral habitat and younger, more open forest, and these tradeoffs must be taken into account when managing for biodiversity.
Replanting after Wildfire
The pathway for replanting after wildfire seems particularly relevant as we grapple with the destruction left in the wake of another terrible fire season.
Replanting can help stabilize soil and prevent runoff
Propagate the regeneration of forests at a much faster pace, especially in high intensity burn areas
Replanted forests bring all of their other ecosystems services (increased wildlife habitat, biodiversity, improved water quality) along with them.
In reality, there are a lot of other things that take priority after a fire—attending to the impacted communities, dealing with erosion, flash floods, and runoff, etc. Although the US Forest Service has historically pushed for extensive replanting, even the most cost-effective seeding methods are still extremely expensive, and the increased number and intensity of the fires are expanding the amount of impacted land, making it hard to keep up. There is also growing concern about the disruption of natural succession and the use of non-native species in replanting, for faster growth to provide quick ground cover and soil stabilization. Lastly, replanting after wildfire’s contribution to carbon sequestration is seemingly low based on study estimates, but there is a lack of research that really looks into and quantifies its potential in Washington.
Ultimately, both of these NCS forest pathways can contribute to Washington’s emissions reductions, but exactly how they are implemented will be challenging—both in figuring out the details and, more importantly, applying them in thoughtful and equitable ways. An important next step will be working with communities living near and within Washington’s forests, to listen to their needs, concerns, and ideas.
Why I Study Climate?
When I started my Masters at UW’s School of Marine and Environmental Affairs, I was excited to learn about the Program on Climate Change and the Climate Science Certificate that I could complete along with my degree. As climate change is both one of the most pressing issues we face, and is also inextricably linked with marine and environmental affairs it felt like the right choice to deepen my understanding and work towards potential solutions. So when the TNC Natural Climate Solutions (NCS) internship came up this past summer, it seemed like another great opportunity that would let me explore potential climate change solutions in Washington State.