Published 7:00 am Thursday, September 24, 2020
In a forested area near the tiny town of Riddle on Oregon’s west side, Ken Carloni kneels to examine a native orchid. His white ponytail juts out from under a newsboy cap. To the south, a mosaic of meadows, oak woodlands and conifer forests blankets the land owned by the nonprofit Yew Creek Land Alliance.
The timber industry knows Carloni, a forest ecologist and retired professor at Umpqua Community College, as an advocate of sustainable forestry management. His latest project with the YCLA has given him an opportunity to put theory into practice.
For the past two years, Carloni and YCLA have worked on a restoration project that involves harvesting evergreens that have crowded the native oak trees and disposing of the leftover slash piles not by burning them but by making biochar.
Biochar is a special kind of charcoal known to improve soil health and sequester carbon.
What makes YCLA’s effort particularly unique is the biochar is made from forest slash onsite and added directly to the soil. This eliminates the expense of hauling slash to stationary kilns that challenges the economic viability of biochar. And because biochar is mainly carbon, it may also be valuable for its role in carbon sequestration, Carloni and others say.
The project represents the first time the Conservation Stewardship Program under USDA Natural Resources Conservation Service has supported biochar production as a forest management tool on private land.
YCLA has 380 acres, and its mission is to improve management of the forest and make biochar in a profitable way that creates jobs.
So far, YCLA has been successful.
“It’s really gratifying to work on something that everyone supports,” Carloni says.
Creating jobs is important to Eric Stauder, a restoration technician with YCLA. Stauder grew up in Roseburg, Ore., a community that has struggled to replace lost logging jobs since the mid-1990s.
“There is a huge opportunity here,” Stauder says of biochar. “We can store carbon for millennia, improve ecological integrity and explore a wide range of beneficial applications with a byproduct of forest management that is usually wasted.”
Stauder is also coordinator of the Phoenix Youth Corps, a program of the Oregon Youth Conservation Corps, which connects students to service projects in their community. For the YCLA project, Stauder and his students have helped thin the conifers that were crowding native oaks.
Native oak woodlands are dynamic, fire resilient ecosystems that scientists say could help mitigate habitat loss from climate change and preserve biodiversity. Conservation biologists regard oak-dominated habitats as some of the most productive ecosystems in North America. Oak trees are habitat magnets that support over 700 associated plants and 200 wildlife species.
Oregon white oak is especially well-adapted to fire. It is less flammable than most conifers and has an open branch structure that minimizes fires high in the tree.
Western Oregon used to be dominated by white oak, but today less than 15% of oak woodlands remain. Most are on private land such as YCLA’s.
Government agencies offer landowners funding for oak restoration and conservation projects, but Carloni hopes his biochar research could make it economically viable without the subsidies.
For his doctoral research at Oregon State University, Carloni studied indigenous burning practices in southwestern Oregon. Native Americans used what Carloni calls “domesticated fire” to manage the great swaths of oak habitat that dominated the region for 6,000 years. These burns were more frequent and less intense than wildfires today.
Since 2002, Carloni has tracked the region’s fires with satellite imagery and fire intensity maps, which he says show that commercially managed evergreen forests burn more swiftly and severely than mature forests.
According to Dominick DellaSala, president of the Society for Conservation Biology, “studies in Oregon and elsewhere show plantation forests burn in the most uncharacteristic forest fire. Because of the way the trees are so tightly spaced together like tight-packed kindling, plantations are a fire hazard.”
The YCLA property was part of a ranch that was extensively logged through much of the 20th century. The conifers were logged and the less profitable hardwoods were left. The ranch went bankrupt in the 1960s, and land management came to a halt. Conifers have been crowding the oaks since.
YCLA is thinning the conifers to create fuel breaks and to free giant legacy oak and madrone trees from the tangle. Many of the conifers have gone out on log trucks to local mills, but many more are being turned into lumber onsite with a portable sawmill.
The thinning also produces lots of branches and other slash that are highly flammable. The cheapest way to deal with it is to pile it and burn it. But open burn piles can damage soil, release greenhouse gases such as carbon dioxide and still run the risk of feeding wildfires.
Plus, it wastes biomass that could be converted into biochar.
Biochar is created through a process called pyrolysis, in which biomass is heated to high temperatures with low levels of oxygen to avoid combustion.
Open burn piles reduce the biomass to ash, releasing most of its carbon into the atmosphere as smoke and carbon dioxide.
Pyrolysis, on the other hand, bakes most of the carbon into the final product, biochar.
In turn, biochar can accomplish a lot when it’s returned to the soil. Its structure works like a sponge for water and nutrients, it neutralizes soil acidity, and soil scientists say it has the potential to store carbon in the ground for centuries.
More farms are turning to biochar for its ability to improve soil fertility. But hauling woody waste to an industrial-scale biochar plant takes time, money and energy. Transportation costs associated with centralized biochar production make it too expensive for most forestry applications.
Carloni wants to look at biochar as a service — made in and for the forest.
“Site-made biochar is more like the pulse of char that comes in after a forest fire,” Carloni explained. “We’re really mimicking what happens in nature,” giving the forest the ecological benefits of fire without the destruction.
One goal of the YCLA project is to design and build portable, efficient kilns that small and large operations could use to make biochar onsite. Some models were fabricated by students in the welding program at the local community college. Carloni even designed one made out of salvaged solar panels.
But not all biochar is created equal.
The small amounts of biochar that open burn piles make contain less than 5% of the original feedstock’s carbon. The mobile kilns make biochar with up to 40% of the carbon remaining.
Carloni is also helping to develop best practices for site-made biochar.
“Conventional wisdom is that biochar fuel must be dry,” Carloni says, “but our preliminary data show (using) green feedstock to be just as effective.”
But producing biochar is more expensive than open-burning slash. “We can’t compete with hand-pile-and-burn contracts unless we get credit for the carbon sequestration,” Carloni says. Scientists believe biochar can store carbon in the ground for hundreds of years that would otherwise go into the atmosphere. That makes it an ideal product for carbon offset markets, which could enable biochar makers to sell credits.
With big high-tech companies such as Apple and Google purchasing carbon credits, the market offers forest managers, farmers and others the opportunity to cash in.
“It all comes down to the life cycle analysis,” says DellaSala, who worked on both of the Oregon Global Warming Commission’s carbon task forces. “You have to be able to trace carbon as it passes through the system. Where does it come from? How much was released when it was produced from something else? How much does it store and for how long?”
Biochar’s carbon sequestration power is compelling, DellaSala says, especially considering the massive role Oregon’s forests play in global carbon sequestration.
Carloni is looking for funding to analyze biochar’s life cycle and measure kiln emissions to lay the groundwork for a biochar certification process.
As policy-makers explore ways to promote carbon sequestration in forests, landowners may eventually see new economic and ecological potential in that pile of slash, he said.
