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Posts Tagged: biomass

Want to limit carbon and curb wildfire? Create a market for small trees

Clearing California's forests of dense overgrowth is a critical first step for curbing catastrophic wildfire in the state. But forest restoration — whether through prescribed burning or thinning — comes at a high price: Not only are these treatments costly, but cutting down or burning vegetation can release stored carbon dioxide, accelerating the impacts of climate change.

new analysis by researchers at the University of California, Berkeley, provides a roadmap for how the state can effectively reduce wildfire risk through forest thinning while continuing to limit its carbon emissions.

By creating a market for small diameter trees and other woody biomass — particularly by encouraging the use of long-lived “innovative wood products,” such as oriented strand board — the state can both create an economic incentive for effective forest management and prevent the carbon stored in this vegetation from entering the atmosphere.

“It's hard to manage our forests without releasing carbon,” said study first author Bodie Cabiyo, a Ph.D. candidate in UC Berkeley's Energy and Resources Group. “But if we're really efficient and careful about how we are using the wood and invest in innovative wood products that can use waste wood, then we can achieve both net carbon benefits and wildfire mitigation benefits in California.”

In 2018, former California Gov. Jerry Brown committed the state to achieving full carbon neutrality by the year 2045, a goal that will require both reducing emissions and investing in carbon sinks, such as forests, that can remove existing carbon from the atmosphere. Two years later, California and the U.S. Forest Service jointly committed to managing a total of 1 million acres of state forest land annually through thinning, prescribed burning and industrial harvesting — treatments that could send some of that carbon back into the air.

“A lot of people are pointing towards forests as a source of sucking carbon out of the air and not adding carbon to the atmosphere,” Cabiyo said. “And while the goal to manage a million acres per year is fantastic and absolutely necessary, the reality is that a million acres per year will cost a lot of money to manage, and it's still unclear where that money is going to come from.”

Forest thinning treatments can generate massive piles of wood residues that are often burnt or left to decay, releasing carbon dioxide into the atmosphere. UC Berkeley photo by Bodie Cabiyo

While data is limited on exactly how much of the state's forests are currently managed, the researchers estimate that it is currently much less than the 1 million acre-a-year target. Their analysis shows that, with the right set of policies and incentives, the use of innovative wood products could provide both the state and private landowners with necessary funding to expand forest thinning treatments while still limiting carbon emissions.

“California has been on the forefront of both climate change mitigation and adaptation,” said study senior author Daniel Sanchez, an assistant cooperative extension specialist in UC Berkeley's Department of Environmental Science, Policy, and Management. “We hope our study helps align these two goals, showing how the state can meet both its emissions reduction goals and reduce wildfire hazard, while providing a framework for managing temperate forests across the world while trying to meet the needs of a changing climate.”

Burn piles the size of school buses

To create forests that are more resilient to severe wildfire, forest managers usually focus on removing smaller trees and underbrush, leaving many of the larger and more fire-resistant trees in place. However, while larger trees can be harvested and sold to sawmills as timber, the smaller wood residues produced by forest thinning have little market value in California and are often burned or left to decay.

“If you drive through these forest treatment projects, you'll see massive burn piles that can be over 20 feet tall — the size of multiple school buses — and they're just sitting there waiting to be combusted,” Cabiyo said. “That's a lot of carbon that is going to go back into the atmosphere.

Small trees and woody residues aren't useless, however. Industries in other parts of the world, including the southeastern U.S., create engineered lumber by mixing wood residues with adhesives and then compressing them into large sheets. This engineered lumber is strong enough for construction, and many houses in California are already built with imported engineered wood, Sanchez said.

Woody residues can also be converted in biofuel plants to create electricity or liquid fuels, and if these plants are outfitted with carbon capture technology, this energy can be produced while removing carbon dioxide from the atmosphere.

Using machines to manually remove small trees and underbrush poses fewer risks than prescribed burns, but often comes at a much higher cost. Photo by Evett Kilmartin

“When it comes to carbon storage or sequestration, some people focus only on what's in the forest,” Sanchez said. “We wanted to assess the carbon emissions associated with the whole life cycle of these new products.”

The study calculated future carbon emissions under both a business-as-usual scenario, assuming limited forest management, and a scenario in which the state has created a market for wood residues. To make the comparison, the researchers conducted a cradle-to-grave analysis, looking at the carbon emissions associated with every single life stage of a product — from the moment the wood is harvested until the end of the product's life.

By investing in local industries that create innovative wood products or that convert biomass into biofuels using carbon capture technology, the state could create a market for wood residues that does not add significant carbon emissions, the study found. The study also proposes a model scenario in which the state incentivizes the use of engineered wood in the construction of multi-unit affordable housing.

“If California starts doing thinning treatments at a large scale, then we're going to be producing a lot more lumber and wood residues, and where that material goes is a question,” Cabiyo said. “We found that using that new material for building affordable housing could produce massive carbon benefits, largely because those buildings otherwise would be built with steel and cement, which have significant carbon emissions associated with them.

Thinning treatments also reduce the risk of severe wildfires that can incinerate millions of acres of vegetation at once and kill even large trees, helping California's forests maintain their long-term ability to store carbon. Study co-author Brandon Collins, a research scientist with Berkeley Forests and with the U.S. Forest Service, points out that these treatments have also been shown to provide numerous ecological benefits, including increased water availability and habitat diversity.

“Creating a market for forest biomass produced by forest thinning could reduce wildfire hazard, prevent air pollution from smoke, and potentially displace fossil fuels and increase water availability,” Collins said. “We need to deal with this small diameter biomass, and there is a solution if we could just find a way to connect the dots politically and economically.”

Additional co-authors of the study include Jeremy S. Fried of the U.S. Forest Service and William Stewart and Jun Wong of UC Berkeley. This research was supported in part by a National Science Foundation Graduate Research Fellowship and the Conservation 2.0 Program.

Unlike large timber, small trees usually cannot be sold to sawmills to recoup some of the cost of the forest thinning treatments. UC Berkeley photo by Daniel Sanchez
Posted on Monday, December 13, 2021 at 10:58 AM
  • Author: Kara Manke, UC Berkeley
Focus Area Tags: Natural Resources

Scientists Focusing on Insect Biodiversity and Insect Decline

If you're looking for a thought-provoking discussion on insect biodiversity and decline, mark your calendars. Chemical ecologist and conservation...

Leslie Saul-Gershenz of UC Davis will speak on
Leslie Saul-Gershenz of UC Davis will speak on "Is Insect Biodiversity, Biomass and Abundance Declining?” at the Hillside Club's Fireside Lecture Series, Berkeley, on March 2.

Leslie Saul-Gershenz of UC Davis will speak on "Is Insect Biodiversity, Biomass and Abundance Declining?” at the Hillside Club's Fireside Lecture Series, Berkeley, on March 2.

Conservation biologist Norm Gershenz is the CEO of SaveNature.Org.
Conservation biologist Norm Gershenz is the CEO of SaveNature.Org.

Conservation biologist Norm Gershenz is the CEO of SaveNature.Org.

Posted on Friday, February 21, 2020 at 4:20 PM
Focus Area Tags: Agriculture, Economic Development, Environment, Innovation, Natural Resources

What to do with woody waste in forests?

The destructive Rough, Valley and Butte fires have raised awareness of the abundant wildfire fuels in forests, leading to calls for thinning to reduce fire risk. But where should land managers put the small trees, limbs and treetops they remove? How does thinning affect forest structure, wildlife and pests? The latest edition of UC Agriculture and Natural Resources' California Agriculture journal contains a collection of peer-reviewed research articles on forest biomass energy, ecosystems and economics.

One way of disposing of the woody material is to burn it in biomass power plants to generate energy. However, nearly half of the power plants in California that run on woody biomass are operating on contracts that are set to expire in 2016, and low-cost solar power may deter utilities from renewing those contracts.

In his Outlook article, “The wood in the forest: Why California needs to reexamine the role of biomass in climate policy,” Peter Tittmann, academic coordinator for the Woody Biomass Utilization Group at UC Berkeley, writes, “By incentivizing better forest management and improved forest health, biomass energy leverages considerable climate and other environmental benefits beyond the direct reductions in carbon emissions from generating electricity from a renewable resource.”

UC scientists are evaluating the feasibility of using small, portable biomass power generators that could be moved to a forest thinning site, reducing the cost of transporting the biomass to a plant. Electricity generated in remote locations could be sold for a premium. Read more in “Following the fuel: How portable biomass energy generation may help rural communities.”

At Blodgett Forest Research Station, an excavator (left) loads forest slash into a horizontal grinder. Wood chips from the grinder are then conveyed into chip vans (center) for transport to Buena Vista Biomass Power plant (right).

Peer-reviewed articles:

Forest biomass diversion in the Sierra Nevada: Energy, economics and emissions

In a Sierra Nevada case study, converting forest waste to electricity yielded energy and emission benefits, but was not economically viable. The authors suggest financial incentives for reduced air pollution could compensate.

Effects of fuel treatments on California mixed-conifer forests

Contrary to what some environmentalist advocates have argued, prescribed fire, mastication and thinning to modify wildfire behavior may have positive effects on the ecology of yellow pine and mixed-conifer forests.

Thinning treatments had minimal effect on soil compaction in mixed-conifer plantations

In mixed-conifer plantations in the Sierra Nevada, no large impacts were seen from commercial thinning or chipping treatments.

Modeling fuel treatment impacts on fire suppression cost savings: A review

Fuel treatments appear to reduce future fire suppression costs, but the savings are unlikely to fully offset the cost of the treatments.

To read all of the articles in the current California Agriculture, visit

California Agriculture is a peer-reviewed journal of research in agricultural, human and natural resources published by UC ANR. For a free subscription, visit, or write to

Posted on Monday, October 19, 2015 at 12:32 PM

Generating energy from forest products

Thinning a forest of woody materials has multiple objectives. It can increase the resiliency of the remaining trees from the effects of fire, drought, pest and disease; it can improve habitat quality for wildlife including watersheds; and it can make it easier for firefighters to protect human lives and livelihoods when a fire is burning. There are several ways thinning is carried out:  cable logging, feller bunching, conventional tractor skidding, hand-thinning and piling, and mastication. One of the issues with thinning is the disposal of biomass that is non-merchantable (e.g., branches, tree tops, small diameter trees). Typically this material goes into large slash piles. For the most part, these piles are left in the forest to break down naturally under winter rain and snows, and are later burned. Because of strict air quality rules, forest managers have very small windows of opportunity to burn these piles, so they are often left on the landscape for many years, sometimes becoming a fire hazard themselves.

Forested communities are searching for ways to deal with this residual biomass that will improve the health of the forest ecosystem; improve and protect critical watersheds and wildlife habitat; reduce the amount of air pollution by removing the piles instead of burning them; and reduce the critical fire danger to their communities. The Placer County Biomass Program is taking up this challenge by chipping the slash piles and trucking the chips to a biomass facility to be converted into electricity.

Outside of Foresthill, Calif., the Tahoe National Forest American River Ranger District and the Sierra Nevada Adaptive Management Project (SNAMP) have been collaborating on a study of forest fuels reduction treatments carried out on national forests. The eight-year ‘Last Chance’ study involves independent third party research by University of California scientists of the integrated effects of forest thinning on fire hazard, forest health, wildlife, water quality and quantity, and public participation. The Placer County Biomass Program, in conjunction with the Tahoe National Forest, the Sierra Nevada Conservancy (SNC) and the Placer County Air Pollution Control District, proposes to remove some of the biomass waste from the Last Chance project to provide an alternative to open burning of the piles. Local contractors are hired to grind the material on-site, load the material into chip vans, and bring the material to market within 60 miles of the Last Chance site to create green, renewable electricity. Placer County estimates that roughly 3,000 Bone Dry Tons (BDTs) of biomass can be removed. According to UC researchers, one BDT burned in a typical commercial boiler fuel will produce 10,000 pounds of steam and 10,000 pounds of steam will produce about 1,000 horsepower or generate 1 megawatt hour (MWH) of electricity.

The economics of this project will be used as part of the assessment of locating a biomass energy facility in the Foresthill area. The removal of these biomass piles will greatly reduce the possibility of catastrophic fire to the local communities on the Foresthill Divide. The improved forest and watershed health will be noticed by the local community and the surrounding county which derives recreation and watershed benefits from the American River area. In addition, several tons of air pollutants will be avoided by removing the pile burns from this area which is currently a federal non-attainment basin that carries both business and health risks to the local population.

Though this project is of benefit to the Foresthill community, other communities in the wild-land urban interface aren’t as lucky. According to Brandon Collins, research scientist at the Pacific Southwest Research Station and UC Berkeley, the lack of funding to chip and remove slash piles and the lack of infrastructure or facilities to take the chips to, makes it impossible at this time to remove that biomass at a larger scale.

“There is so much woody material on the landscape as a result of fire exclusion, it could take decades to really get a handle on it," Collins said. "However, any effort to remove thinning residues from the forest and to also get a benefit from it, such as energy, is great and should be supported.”

Slash pile in Tahoe National Forest, Last Chance project.
Slash pile in Tahoe National Forest, Last Chance project.

Slash pile under a controlled burn.
Slash pile under a controlled burn.

Workers bunch slash.
Workers bunch slash.

Slash piles are chipped and trucked to biomass facility.
Slash piles are chipped and trucked to biomass facility.

Posted on Friday, November 8, 2013 at 8:21 AM

Rice growers optimistic; seeking biomass growers

Rice harvest has started in Sutter County.
The (Marysville) Appeal-Democrat checked in on the rice harvest which started recently, with an article by reporter Ashley Gebb. USDA reports that harvested acreage for rice in California is up 6 percent this year, to 588,000 acres; in 2010, Yuba and Sutter counties had approximately 154,000 acres planted in rice. The reporter talked to Chris Greer, UC Cooperative Extension farm advisor for Sutter-Yuba and Colusa counties, about what this summer's cooler weather means for the rice harvest. "Overall things look pretty good from a yield standpoint," he told the reporter. "We will have to see what the numbers come out. From what we are seeing, we are pretty optimistic on the prospects."

Harvesting jet fuel
Kathy Johnston, (San Luis Obispo) New Times

Reporter Kathy Johnston examined both government and grower interest in camelina sativa, an oilseed crop that can be used in jet fuel. Growers interested in camelina can sign up for USDA's Biomass Crop Assistance Program, the deadline for which has been extended. The reporter talked with Steve Kaffka, UC Cooperative Extension agronimist in Davis and director of the California Biomass Collaborative, who is seeking cooperating growers for trial plantings of camelina under local conditions this winter. “It hasn’t been adapted specifically for California. We’re trying to figure out what conditions it likes, the range of rainfall and soil types where it might be suitable in San Luis Obispo County,” Kaffka told the reporter.

She also talked to Royce Larsen, UC Cooperative Extension natural resources advisor in San Luis Obispo county, who explained that though meetings about the crop have been well attended, no San Luis Obispo growers have signed up for the program yet. “A lot of people showed up [at a meeting about camelina in Templeton] with great interest, but they left, I think, a little downhearted,” Larsen told the reporter. “The bottom line is it’s too new, with too many unknowns for people to want to jump on board and give this a try."

(Though this article is about San Luis Obispo county, other California counties included in this project area are Butte, Colusa, Fresno, Glenn, Kern, Kings, Madera, Merced, Riverside, Sacramento, San Joaquin, Solano, Stanislaus, Riverside, Tehama, Tulare and Yolo, according to an article on the California Ag Network website.)

Posted on Thursday, September 22, 2011 at 10:16 AM
Tags: biofuel (12), biomass (3), camelina (1), Chris Greer (7), rice (21), Roy Larsen (1), Steve Kaffka (4)

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