ALBUQUERQUE, N.M. -- As the largest single manager of forests in the United States, the Forest Service could be a major supplier of carbon credits to the emerging voluntary carbon market. But some major challenges need to be overcome before the agency's 193 million acres of forests and grasslands can be effectively used as a tool to combat climate change, Forest Service Chief Tom Tidwell said.
During the Society of American Foresters annual meeting here last week, Tidwell said he remains concerned that placing a monetary value on carbon absorbed by national forests, then selling credits based on that storage capacity, could crowd out private forest owners who hope to use sequestration projects as a new source of income.
"We have to be careful not to provide a disincentive for private lands," Tidwell told Land Letter. "Internationally, there's a lot of competition for the money that's available" from selling carbon credits.
While private forests, which comprise 63 percent of the United States' total forested area, store more carbon overall, Forest Service studies indicate that federally owned forests contain an average of 28 percent more carbon per acre than private stands.
A report issued by the agency last month found that U.S. forests store 41.4 billion metric tons of carbon, adding 192 million metric tons of carbon each year, which offsets about 11 percent of domestic industrial greenhouse gas emissions annually. And that number is expected to grow as forest acreage expands and more areas are managed to enhance carbon sequestration, the report found (ClimateWire, Oct 15).
But Tidwell cautioned against an over-reliance on national forests as carbon sinks, noting that the Forest Service's mission is to manage its holdings for multiple uses, including timber production and recreation. And a shift in public values has led to a greater emphasis on federal forests' role in protecting clean water, wildlife habitat and other conservation benefits, he said.
"Carbon management has to be just one ecosystem service," Tidwell said. "I don't see it ever driving forest management. But it's a key benefit, and it's something we need to consider in forest planning."
The Forest Service has established a few small pilot projects in recent years to explore how national forests can help address climate change, said Dave Cleaves, the Forest Service's climate change adviser.
"We think if we maintain healthy systems, [the forests] will gravitate toward a long-term carbon situation that can be sustained," he said. "Our intent is to integrate carbon management into our multiple-use objective."
During a speech at the Society of American Foresters conference, Tidwell noted that the agency has shifted its management focus toward restoration forestry -- marked by thinning, controlled burns and other forest rehabilitation practices -- and away from traditional timber production, which dominated national forest management for most of the 20th century.
Prescribed burns and thinning are intended to improve forest conditions after a century of fire suppression, which resulted in the overcrowding of trees. In recent decades, managers realized that naturally occurring, low-intensity wildfires play a key role in sustaining ecosystem health in many forest types. And while some carbon is released during controlled burns, forest experts believe that clearing fuels reduces the risk of large, severe fires that emit more carbon into the atmosphere.
The jury is still out, however, on whether forest restoration projects will aid in long-term climate mitigation efforts.
David Diaz, a forest carbon expert with Ecosystem Marketplace, which provides data and information on carbon markets, said thinning projects can reduce the risk of big, super-hot fires that emit more carbon, but they also remove a lot of carbon-sequestering trees.
"Thinning involves a pretty extensive removal of biomass from the forest -- more than would occur in a wildfire," he said, adding that about 30 percent of a forest's aboveground carbon is released in a wildfire, and that some of that lost carbon is restored by post-fire regeneration.
And while Diaz said he understands why Tidwell and others are wary of bringing national forest lands into the carbon credit market, he believes that with effective safeguards, public and private forests can both be used to generate carbon credits.
"The idea of flooding the market is definitely something that's been raised by different observers, but it's not one of my top concerns," he said.
Meanwhile, other public lands agencies have begun experimenting with carbon financing.
In California, Cuyamaca Rancho State Park, where about 25,000 acres burned in a fire a few years ago, is hoping to use proceeds from selling carbon credits to generate income for reforestation projects.
And observers say that the forest carbon market will continue to grow regardless of whether greenhouse gas emissions are regulated, either under a cap-and-trade system or by across-the-board cuts.
"Demand for offsets in voluntary markets persists and will grow with or without federal legislation," said Matt Smith of Finite Carbon, which develops forest carbon projects for landowners.
Click here to read the Forest Service report.