For over 40 years, the anti-forestry movement rallied around saving the “last of the old growth” on federal lands, as if entire national forests had been logged into moonscapes and only a few big trees remained.
More recently, they cheered when President Joe Biden signed his executive order on Earth Day 2022, directing his agencies to embark on a costly and time-consuming exercise to define and inventory these last remaining mature and old growth forests.
The administration released its report a year later. What did they find? There is no shortage of mature and old growth trees on lands managed by the U.S. Forest Service and Bureau of Land Management (BLM) based on regional definitions of these forest types developed in the 1990’s.
On the 193 million acre National Forest System alone, the U.S. Forest Service found 24.4 million acres of “old growth” and 67.4 million acres of “mature” forest – about 143,000 square miles, larger than the state of Montana. In total, these forests make up a combined 63 percent of inventoried Forest Service and BLM lands.
Many of these forests are on lands that would likely never be logged, because three-quarters of NFS lands are largely off-limits to active forest management and timber harvest under existing forest plans and land set-asides like Congressionally-designated Wilderness areas.
And the inventory did not count mature and old-growth forests on the millions of acres on National Parks, National Wildlife Refuges, state parks and other public lands where forest management is largely prohibited.
Through the Inflation Reduction Act, the federal government spent $50 million and countless agency staff time to define and inventory these forests, when data already indicates that severe wildfire and insect infestations are the leading contributor to large-scale losses of big and old trees, not timber harvest. As harvest has declined dramatically on federal land, annual acres burned has increased sharply.
As the Society of American Foresters noted, the inventory analysis did not measure the health of our federal forests or account for alarming levels of tree mortality and carbon emissions associated with overstocked and unhealthy forests. Many forests in western states are now emitting more carbon than they sequester annually.
Yet activists are clamoring for further restrictions on forest management, as if wildfires were not a threat at all.
“It’s extremely encouraging that the Biden administration is recognizing the value of mature and old-growth trees,” said Earthjustice’s Blaine Miller-McFeeley told the Washington Post. He said his group supports rules “that will protect and restore climate forests for future generations from the threats they face today, including unnecessary logging.”
If the goal is really to reduce net carbon emissions and address climate change, one of the best things we can do is to actively manage forests to reduce the risks of massive carbon-emitting wildfires, and to store carbon in long-lived wood products.
Researchers at the University of Washington recently completed a study estimating the climate mitigation role of forests in Washington State, factoring in natural and harvest-induced biogenic carbon flux in the forests and associated biogenic carbon flux in wood products.
The study compared the net CO2 sequestration by major landowner type – U.S. Forest Service, Washington state trust lands, and privately owned forests – including the carbon stored in forest and wood products, as well as emissions from wildfire, mortality, and harvest. The study suggested that managed forests sequester carbon at a greater rate than unmanaged forests and have significantly lower tree mortality.
In this case, Washington’s managed forests grow 70 percent faster per acre (4.92 tons of CO2 per year) than the unmanaged Forest Service lands (2.88 tons of CO2 per acre per year). While managed forests lose about 14 percent of their annual growth to tree mortality, disease, and wildfire annually, unmanaged federal lands lose 71 percent of their growth due to these disturbances.
Dead and dying trees do not sequester carbon, they only emit carbon over time as they decay. That’s why the Biden Administration should start accelerating active forest management on lands that are unreserved, and where thinning overstocked stands can make a difference. Doing so would help conserve forests of all ages.