Defining “old growth” is a futile exercise when our forests are burning

The U.S. Forest Service and Bureau of Land Management are seeking public input to define and inventory “old-growth and mature forests” on federal lands in their first step toward complying with the Biden Administration’s Earth Day executive order, which identified “climate impacts, catastrophic wildfires, insect infestation, and disease” as the primary threats to all forests, including older forests.

Unfortunately, this attempt to “define and inventory” directly undermines the administration’s own 10-year wildfire strategy that aims to treat up to an additional 20 million acres on National Forest System lands through thinning, logging and controlled burning, and up to an additional 30 million acres of other Federal, State, Tribal, and private lands.  Such treatments have helped public lands managers and firefighters save large, old and mature trees from destruction, including the iconic Giant Sequoias in California.

Rather than focusing on confronting our national wildfire and smoke crisis through climate adaptation strategies and active forest management, federal agencies must now spend time and resources developing a “universal definition framework” of old-growth and mature forests across incredibly diverse and complex forests with widely different tree species, sizes, characteristics and needs.

It is an impossible and unscientific task to come up with a single definition of old-growth that applies to forests from Florida to Washington State.  Any single definition of old-growth and mature forests could be so general that it’s useless in guiding forest management across the nation, or so specific that it leaves out forests that some would consider mature.

At a time when we need more management on fire-prone federal lands, this is a formula for more bureaucracy and red tape that further ties the hands of our public lands managers. And for some, maybe that’s the point.  Activist groups are using this “define and inventory” process to push for more anti-logging regulations, even though only 35 percent of National Forest System lands are available for regular timber harvest.

They point to the 2001 Roadless Rule as a model policy that restricts active forest management and road building on millions of acres of federal lands. Yet more than 37 million acres of National Forests have burned since the Bill Clinton-era Roadless Rule was adopted, an acreage more than seven times larger than the acres where any timber harvest has actually occurred during this time.

Most lands managed by the federal government are already off-limits to logging, or have restrictions that make active forest management infeasible. This includes 17.6 million acres of NFS lands in Wild & Scenic River Corridors and 36.6 million acres of NFS lands that are in Congressionally Designated Wilderness Areas.

The 58.2 million acres of NFS lands in Roadless Areas is larger than the entire National Park System, where forest management is also prohibitive. Similarly, forest management is extremely limited in the 85-million-acre National Wildlife Refuge System.

The lack of active forest management comes at a cost when it comes to mitigating climate change. Wildfire, drought, insects and diseases, and the resulting high tree mortality have reduced the ability of federal lands to sequester and store carbon. Fires are burning so hot some forests are failing to regenerate naturally.  Efforts to restrict management of “old growth and mature” forests ignore the fact that forests are dynamic ecosystems where disturbance events can reset 100- to 200-year-old forests to zero in the course of a single day.

The worst thing we could do during a climate crisis is to walk away from our public lands and decide not to use the tools available to help adapt these lands to changing conditions. Due to the diversity of forests in our nation, a universal definition of old growth and mature trees can’t be determined by the best available science. It can only lead to more arbitrary policies that limit the ability of federal agencies to manage for specific species and will lead to less old-growth on the landscape over time.

Defining “old growth” is a futile exercise when our forests are burning