I’ve been wondering if there is a straightforward answer to the question of how to best manage forest lands to sequester carbon for the foreseeable future to reduce potential climate change impacts. We’ve beaten around that bush a few times, such as here.
I thought such an answer might be found in the kind of forest management activities carbon offset programs are willing to pay for. I recently ran across this example, which describes two new programs for small forest landowners.
“Forest carbon projects have historically faced skepticism around their additionality and potential for leakage — that is, the shifting of tree removals to nearby acreage. The concern is that despite paying a landowner to keep trees on one parcel, the same number will simply be removed elsewhere, resulting in a null offset with no net change in carbon storage. Yet SilviaTerra believes this problem can be addressed by creating a market in which all landowners are eligible to receive carbon payments as an alternative to timber revenues… Payments are scaled to target the timeframe when forests have matured to a point of likely timber harvest… SilviaTerra believes that timber harvest deferrals hold the potential for removing over a billion tons of atmospheric carbon within the United States in the coming decade, or 4.3 billion tons globally.”
SilviaTerra is paying landowners to not harvest mature trees now, and presumably they would continue to do that indefinitely for a parcel because, (according to this article on the carbon value of old forests), “We now know that the concept of overmature forest stands, used by the timber industry in reference to forest products, does not apply to carbon.” The Family Forest Carbon Program pays for “improved forest management practices,” “such as removal of invasive species or limiting thinning.” Both seem to treat the answer to my question as obvious – the best management for carbon is “don’t cut down trees.”
Here is what the Forest Service has had to say about the best available science. This 2017 General Technical Report covers a lot of the pros and cons and questions and considerations and reservations that we have previously discussed, such as wood products, wood energy and fire risk, but if the goal is to “maintain and increase carbon stocks,” the best answer appears to be “decrease carbon loss:”
“Decreasing the intensity of forest harvest is one way to decrease carbon losses to the atmosphere (McKinley et al. 2011, Ryan et al. 2010). Across diverse forest systems, the “no harvest” option commonly produces the highest forest carbon stocks (Creutzburg et al. 2015, Nunery and Keeton 2010, Perez-Garcia et al. 2007).”
The Report was written for a broad audience of landowners and managers, so it also discusses options for managed stands:
“Managed stands typically have lower levels of forest biomass than unmanaged stands, even though the annual rate of sequestration may be higher in a younger forest. In managed forests, reducing harvest intensity, lengthening harvest rotations, and increasing stocking or retention levels will generally increase the amount of carbon stored within forest ecosystem carbon pools in the absence of severe disturbance (D’Amato et al. 2011, Harmon 2001, Harmon and Marks 2002, McKinley et al. 2011, Taylor et al. 2008b).”
However, they also provide caveats and qualifiers associated with obtaining overall carbon benefits from any strategy that removes trees, which make it clear this would likely be a second-best strategy for carbon sequestration.
With regard to national forests, the Report recognizes the role of NFMA and forest plan revisions:
“Assuming carbon is one of these key ecosystem services, the plan should describe the desired conditions for carbon in the plan area that may vary by management or geographic area. In developing plan objectives, the interdisciplinary team should consider the linkage between carbon and how plan objectives would contribute to carbon storage or sequestration. Standards and guidelines may also be needed to achieve desired outcomes for carbon.”
We shouldn’t have to just assume the importance of carbon sequestration, since that is a decision a forest plan could make. With an incoming administration that has said it would integrate climate change into everything it does, a good question to ask them would be why should the Forest Service not establish in its forest plans the desired outcome to “maintain and increase carbon stocks.” This should create a presumption or default that trees should not be removed unless the Forest Service can demonstrate scientifically that it would improve carbon sequestration (apparently difficult to do), or if it would meet some other goal that the planning process has determined is a higher priority than climate change (such as public safety). Climate change mitigation has typically been diverted to a side-channel during forest planning, but there doesn’t seem to be any excuse now for why at least managing for carbon sequestration isn’t mainstream.
In the western US where fires are part of the equation, and climate change is altering conditions, leaving forests to just grow isn’t always the best option (look at all of the mortality in California after the last drought there!). Hurteau and others have done work in California looking at carbon stability, which makes more sense in fire-adapted forests. So while there may be a short-term drop in carbon if stand density is reduced, that carbon will be more stable in the long run.
In terms of carbon, it is also important to talk about additionality. There is how you might manage a forest for economic return or wildlife habitat or water quality, and then there is how much additional carbon can you sequester while accomplishing those objectives and altering the management to increase carbon sequestration.
Jon, I wrote a long article for the August edition of The Forestry Source about SilviaTerra’s Natural Capital Exchange (NCAPX, silviaterra.com/ncapx), which works on one-year terms. Here’s how the pilot project worked, in a nutshell:
“To test this technology and a process that would offer smaller landowners revenue based on the carbon their forests sequester, SilviaTerra established a pilot NCAPX project in six counties in western Pennsylvania. The 21 landowners—with a total of 68,000 acres—who agreed to participate have one-year agreements that ended on July 31, 2020. Microsoft has agreed to purchase $300,000 in forest carbon offsets from these landowners, via SilviaTerra.
The process works like this:
• SilviaTerra uses its Basemap technology to estimate the volume of timber on a parcel, the amount of above-ground carbon sequestered in that timber, and the amount of that carbon that would be removed under business-as-usual management practices.
• The landowner agrees to defer or reduce harvesting for one year.
• SilviaTerra hires a forester to conduct field measurements on the property to verify the amount of carbon sequestered in the timber above the business-as-usual management scenario.
• SilviaTerra sells the carbon credits (to Microsoft, for this pilot project).
• SilviaTerra pays the landowner a pre-agreed per-ton rate for the carbon sequestered.”
Later in the article:
“Our view is that, while we do have a one-year term—and it may not be the same acres every year—these are the lowest-cost acres where you can actually change management,” [SilviaTerra cofounder Max] Nova said. “Ultimately, we’re incentivizing people to push out their rotation age, so across the landscape, it actually increases the average age of forests. Think about the US South, where people are growing loblolly pine on a 26-year rotation. The average age of those stands is 13 years. If we pay them to extend their rotation by a year or more, to 27 or even 28 years, and maybe get that average up to 14 or even 15 years, in aggregate that actually represents an enormous amount of carbon. We think NCAPX offers the lowest-cost path to achieve that.”
One thing I don’t understand is that the same people who say we should end logging in the name of climate change also often promote wood as a sustainable building material that helps reduce climate change. So which is it?
Patrick, I don’t think it’s the same people… there are people who frame the issue as “where will we get our building material” like the Yale folks here…
They get the answer, “wood is better than substitutes.” https://forestpolicypub.com/2020/11/05/yale-hixon-center-webinar-on-mass-timber-friday-november-6-2020/
Other people start at the forest level (usually not dry Interior forests) and go in three directions..
What should federal forests do?
What should private timberland owners do?
What should NIPF landowners do?
How will they balance carbon with their other landowner objectives..? Can we pay them to “do more” for carbon?
Conceivably if folks determined that wood was good for construction, we could decide to import it all from place x where carbon loss would be minimized… like perhaps dry areas that might burn anyway. However, there is no industry to speak of there.. hence, problem. Or we could import from country x, that has determined to sell its trees, but then perhaps it doesn’t matter because we are looking at a worldwide carbon balance.
The last one you mentioned seems the most likely. So the US stops logging any of our forests. Then we just need to import wood from Canada or some other country that still allows logging. In the end you just drive up the cost of wood by making it an expensive import, while still not helping the global carbon balance.
Another thought. How does logging actually reduce captured carbon? Granted there’s some waste product, but the carbon in the wood of my house is just as fixed now as when the trees were alive. With good maintenance and weatherproofing, my house will still be there hundreds of years from now. Possibly longer than the source trees would have been if left in the forest, depending on what kind they were and how long they live. So I don’t see how using wood as a construction material significantly diminishes captured carbon. Unless the wood is burned or scrapped and allowed to rot away, most of the carbon stays fixed.
Heck if all way care about is carbon sequestration, it seems the best way to ensure all that carbon stays trapped would be to cut down all the forests and encase the trees in concrete or something to ensure the carbon can never escape.
“. . . it seems the best way to ensure all that carbon stays trapped would be to cut down all the forests and encase the trees in concrete or something to ensure the carbon can never escape.” Concrete production is a big carbon emitter. Better to sink the trees underwater, e.g., in reservoirs.
Ah.. but they are working on concrete that absorbs CO2. It’s the reducing carbon technology horserace.. who’s going to win? No one knows.
“Other researchers are focusing on different tactics. Sant, the UCLA engineer, is involved with a research team developing a product they’ve dubbed “CO2NCRETE.” The process relies on “carbon upcycling”—using CO2 emissions captured from industrial activities to produce a cement-like, and potentially carbon-neutral, building material. The CO2NCRETE process is unique, Sant says, because it can utilize the captured carbon emissions as is, without the need for extra processing.
Other experts have pointed out that concrete naturally absorbs carbon dioxide. It’s a slow process, but over the course of decades, it may be able to soak up a substantial amount of the emissions it put into the atmosphere in the first place via the limestone heating process.”
https://www.scientificamerican.com/article/cement-producers-are-developing-a-plan-to-reduce-co2-emissions/
Interesting stuff, Jon! Thanks for sharing.
It seems the money for buying carbon credits are coming out of thin air, a Microsoft grant? And these credits are really what? Used how? I am all for longer rotations, but these ideas seem like smoke and mirrors to me.
The Forest Service sure doesn’t need another reason to do nothing.
Jon, you quoted this…
Before I retired we did climate change action plans for each forest. I was the Regional Climate Change Coordinator. We figured the best thing for carbon for our region was to reforest areas that had no trees due to wildfires (e.g. Hayman) and get that tree carbon cranking out right away. Plus restoring more riparian areas.. this had carbon benefits and also adaptation to drought benefits. I remember Trey Schillie doing carbon calculations of some of these things.
For many areas, including watershed protection areas and WUI, not doing fuel treatments due to carbon is a non-starter. Colorado itself has 700K grants for fuel mitigation including thinning trees. But that’s in “the absence of severe disturbance”.. which we seem to be having in terms of forest fires.
Perhaps that is not optimal for carbon but..carbon isn’t everything. It’s one “ecosystem service” of many.
As for me, instead of buying carbon credits, I’d put it into carbon capture innovation markets. Somehow we seem to have gone down a road that decreasing carbon must be the focus of every activity. Whereas in reality, some count more than others toward the goal, and some are more dependable/or controllable than others (ones that don’t depend on assuming forest trees will be around for a long time), and so on. But the good thing about market approaches is that we don’t have to agree.. to each hizzer own.
But putting carbon first (and not resilience) in forest plans would be odd. I’d go for a planning rule targeted towards resilience and not integrity.. though. Oh, the horror of a planning rule. Never mind.
One of the linked articles has a chart that shows reforestation has more potential than forest management so yes there would more payoff there. I’ve also read that management of existing forests is one of the most cost-effective carbon capture mechanisms, and it doesn’t require “innovation.”
You have a good point that carbon sequestration could appear to conflict with ecological integrity (or resiliency if you prefer) in some circumstances, like where there are too many trees for a site to be resilient. I think that has to be reconciled in the larger picture – a disrupted climate is also bad for resiliency, and that could probably justify less emphasis on thinning. I’m only saying that forest planning for a particular forest situation should include that discussion.
This discussion is missing several pieces of the puzzle, one of the most important is that carbon sequestration must be seen in the context of past land use change, including deforestation.
The climate problem is not one of flows (emissions and sequestration), it is one of stable stocks (reserves) being mobilized, that is old growth forests being cut and fossil fuels stored safely in the ground being extracted, processed and burned. If the issue of ‘permanence’ is not addressed when considering issues of forest carbon it is essentially irrelevant for climate purposes.
Another fun fact: Fossil fuel emissions are essentially a one way injection of carbon into the atmosphere (and oceans). The idea that the land sector (i.e. forests) can ‘compensate’ for the burning of fossil fuels is popular, and is at the center of the idea of ‘offsets’ — but it is based on erroneous assumptions and a misrepresentation of how humans are disturbing global carbon cycles. The large corporate NGOs are very responsible for perpetrating the climate science illiteracy that is embedded in the mechanisms of forest-based carbon offsets. History will not be kind to these people who have done industry dirty work and tried to call it environmental management.
Also, the idea of ‘substitution’ (that wood products are better for the climate than other products) is not standing up to scientific scrutiny, check this new article challenging the assumptions about substitution. https://www.nature.com/articles/s41598-020-77527-8
Gary.. I don’t think “standing up to scientific scrutiny” is accurate… I think the fact that there IS controversy among scientists is accurate.
Which corporate NGOs are you talking about?
“that is old growth forests being cut and fossil fuels stored safely in the ground being extracted, processed and burned” … but almost all sawtimber production in the US is not from old growth forests.
I’m not a fan of offsets either, but that is a separate question than the question “is it currently better for reducing excess CO2 in the atmosphere to build with wood than other building materials?”
Is reducing the harvesting level to sequester carbon a good idea? Let’s look a what effect 31 years of reduced harvesting has had on the National Forests.
During the 31 years period ending in 2016, drastic changes took place in the management of national forest resources. Emphasis (dollars|) shifted from tangibles, such as timber, forage, and road construction and maintenance to intangibles (wilderness, endangered species and old growth protection) and fire management.
As a result of these changes , plus chronic under-funding, serial litigation, over-regulation, and over-planning and analysis, timber, harvest has declined by 75% and the forests are now harvesting about 8% of their growth. Mortality due to fire, insects, and disease increased by 200%. (1293 to 3881 MMcf)
As trees in unmanaged forests and under stress from climate changes died in increasing numbers these decaying trees o longer sequestered carbon, but rather became sources of the greenhouse gases carbon dioxide and methane. Prudent harvesting could have used these dead and dying and unwanted trees to replace fossil fuels and less climate-friendly building materials while creating a healthier and more resilient timber stands. Wise use would also create a market for presently unmerchantable material and a new job market in rural areas urgently needing economic assistance
The results of this real-life “experiment” make apparent the long-term adverse effects of non-management.
You have a theory about carbon changes over the last 30 years, but you don’t acknowledge the contribution to sequestration of all that unharvested “growth.” And going forward, the answer to the science question of how to sequester carbon seems to be “let ’em grow.”
Jon, I don’t think that’s fundamentally a science question. The primary question is “how should we as a country best respond to concerns of human impacts on climate change?” Along with adaptation to fires including thinning and pb. Along with providing building materials. You have to make assumptions about all these things..
Yours is a different question than my point about the way to sequester the most carbon through forest management. Your question is also bigger than how to best manage federal lands to mitigate climate change. I don’t think we have to wait to start preserving national forests until the country answers your question (since that would keep active management options open if we later decide that’s a better way).
Meanwhile, in the southern Sierra Nevada, so much of those forests’ ‘sequestered’ carbon is in dead trees. The wood is worthless, and doomed to burn at high intensities, like we’ve seen in the Creek Fire. I saw a video of a person driving away from the fire, surrounded by fat old growth snags, which no longer have their finer branches. Such snags are still highly-flammable, especially around the base. Most of those old growth pine snags have old catfaces, which soon burn all the way through, allowing the entire mass of the tree to burn completely. “Sequestration” might not be the right word to use, in these forests, with these forest conditions. The reality of this situation is very grim.
It would be great if we could just “Let em grow” The reality is that they don’t grow. They die. During 30+ years of of non-management (Let ’em grow” ), mortality increased by 200%. Not an insignificant figure. The dead trees are no longer producing oxygen. They are generating greenhouse gases. Has the management strategy mitigated climate change?
We need to mitigate ALL human impacts, including climate change. We need only to look at other patches of ‘preserved’ lands to see the results, here in California. The forests of Yosemite are being decimated, and some of that is due to humans doing dumb things. Since there will always be humans doing dumb things, shouldn’t we treat that as an ‘environmental constant’, in managing some forests? We cannot preserve our way out of drought, another ‘environmental constant’. With so many wildfires being caused by people, we should put something about it into Forest Plans (where applicable).
I assume that projections of future conditions under forest plan alternatives account for fire risk from all sources. In terms of decisions a forest plan might make, it seems to me that there should be a relationship between how “open” the forest is to public use and the probability of fire starts (as well as the amount and type of management or permitted activities also increasing human presence).
A caveat for my most recent comment. The mortality statistic and other figures given my Dec 1 post apply to national forests in the United States. They are probably not applicable to the much younger stands found on private and corporate land.