Here’s Why No One Can Agree on How to Manage America’s Old Growth Forests

A sign with Smoky the Bear warns of fire risk.
A sign with Smoky the Bear warns of fire risk.
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As the presidential election looms and the odds of a 2020 rematch grow, natural resource management is just one of many issues at stake. The Trump administration emphasized logging, thinning, and “raking” in the name of emboldening the timber and paper industry. Conversely, the Biden administration has reversed most of Trump’s forest policies in the name of climate resilience, carbon sequestration, and biodiversity. In the months before the election, the Biden administration aims to bolster the U.S. Forest Service’s conservation strategies around mature and old-growth forests.   In December, the USDA announced a proposal to add a national plan for old-growth and mature forest conservation to each of the 128 documents that guide USFS operations on National Forest System lands. The proposal comes in response to Biden’s 2022 executive order, which directed the USFS and the Bureau of Land Management to strengthen, restore, and improve the climate resilience of America’s forests. Both initiatives are part of the current administration’s attempt to win on climate issues, particularly with nature-based solutions that are likely to appease an increasingly climate-focused voter base. The amendment, which is still in draft form, wouldn’t so much change USFS policy, an agency representative tells Outdoor Life. Instead, it would be a “furtherance of current policy to protect, maintain and improve old growth forest conditions.” Logging old growth on USFS lands is already pretty restricted under the USFS’ multiple-use framework, which essentially requires that any tree removal on USFS lands is done for ecological reasons first and foremost. Additionally, some 2,700 forest plan components already guide management activity on USFS old growth stands, according to Federal Forest Resource Coalition executive director Bill Imbergamo. The amendment would take this existing policy a step further by prioritizing both old growth and mature forests, the combination of which comprise some 64 percent or 92.8 million out of 144.3 million USFS acres nationwide. It’s clear that the Biden Administration is attempting to walk a fine line between top-down management and allowing USFS district managers the freedom to manage forests locally. As a result, the proposal is being met with a mixed bag of responses from the larger conservation community. Critics remain concerned that the proposal will lock more land away from what they consider necessary active management strategies. Proponents are optimistic that the proposal could help address the greatest risks to America’s forests head-on.  Where Are America’s Old Growth Forests? The USFS has made numerous attempts at defining “old growth forest” and “mature forest” in recent decades, even asking for public comment on the subject in July 2022 shortly after the executive order. The USFS completed an initial draft report in April 2023 that included working definitions for both age classes. (These “definitions” aren’t easy reading. Instead, they’re giant, pages-long charts split up by regions that are full of measurements, abbreviations, and figures.) As clunky as they are for non-scientists, the working definitions were used to inventory the old growth and mature forests of the U.S. This map shows where those forests remain.  A new interactive map shows where the nation’s remaining old growth and mature forests are. Map by the United States Forest Service Alaska is home to lots of old growth forest, particularly in the Southeast. (Hawaii, on the contrary, did not show any data on this map.) Map by the United States Forest Service Most of the nation’s remaining old growth forest is in southeastern Alaska, the Cascades of Washington and Oregon, the Sierra Nevadas of California, the Sawtooths of Idaho, eastern Utah, and western Colorado. Other smaller pockets exist in western Montana, Wyoming, Arizona, New Mexico, and southern Appalachia.  What the USFS classifies as mature forests are more widespread. In addition to huge swaths in the Mountain West, the Northwoods of the Upper Midwest, the Green Mountains of Vermont, the White Mountains of New Hampshire, western Arkansas, northern New Mexico, and much of Pennsylvania’s Allegheny National Forest are all ripe with mature forest too.      Between the working definitions, the inventory, and the map, the USFS has met some of the demands of the president’s executive order. But the next step seems to be using this inventory to influence agency activity. That’s the part that has people talking.  Why Old Growth Forest Management Is Contentious A USFS firefighter works on a prescribed burn. Photograph by USFS In January, the USFS documented the three biggest threats to the health of mature and old growth forests nationwide.  “Currently, wildfire, exacerbated by climate change and fire exclusion, is the leading threat to mature and old-growth forests, followed by insects and disease. Tree cutting (any removal of trees) is currently a relatively minor threat despite having been a major disturbance historically,”  the threat analysis reads. “The analysis also found that two thirds of mature forests and just over half of old-growth forests are vulnerable to these threats.” But Imbergamo says the draft proposal, which claims to address these primary threats, would actually do the opposite. “This is unprecedented, amending all 128 forest plans in 13 months when it usually takes maybe two to five years to amend a single forest plan,” Imbergamo says. “It’s also unnecessary. [The USFS] already has 2,700 other plan components that set standards for managing old growth forests. And it’s unhelpful because it is directly at odds with the threat assessment, which said it isn’t harvest that’s disposing of old growth, it’s wildfire, insects, and disease. But what does the administration put out? A proposal to limit harvest.”  Multiple schools of thought exist for how to best address wildfire in the U.S. The widely held idea that conducting fuel reductions in old growth forests would better protect old growth trees from high-severity fire is logical. But studies have also shown that old growth forests are more naturally fire-resistant than immature forests in some places. Take this example from the Klamath-Siskiyou region of Oregon in 2013 following the Big Windy and Douglas fires. “Somewhat to our surprise, we found that, compared to other forest types within the burned area, old-growth forests burned on average much cooler than younger forests, which were more likely to experience high-severity fire,” USFS wildlife biologist Damon Lesmeister told Phys.org of his study. “How this actually plays out during a mixed-severity wildfire makes sense when you consider the qualities of old-growth forest that can limit severe wildfire ignitions and burn temperatures, like shading from multilayer canopies, cooler temperatures, moist air and soil as well as larger, hardier trees.”   Old growth forests also act as a major global carbon sink, and research shows that trees sequester significantly more carbon as they age. Of course, that point becomes moot the minute those trees start to burn, a major talking point for advocates of actively managing old growth.  All Old Growth Forests Are Unique This debate gets even more complicated because old and mature forests vary greatly. Southeastern hardwood forests have different management requirements than pinyon-juniper forests in the Southwest. What’s “immature” for a bristlecone pine tree might be ancient for an Arizona ash or a boxelder tree. Drought has a stranglehold on forests in the Mountain West. Meanwhile, Vermont and New Hampshire just got done with their wettest summers on record — much of which was spent under the choke of intense wildfire smoke from neighbor-to-the-North Quebec. In other words, forest conditions in North America are anything but homogenous. As a result, opinions on the USFS proposal seem to be tied, at least in part, to locality. “We don’t have a lot of old growth forest in the Southwest,” New Mexico Wildlife Federation executive director Jesse Deubel tells Outdoor Life. “We have old growth forests in different biomes, but they’re fairly rare. I hate to call them a novelty, but when you’re in that habitat type, it’s remarkable. And that habitat is very sufficient to support our big game populations … I know it’s necessary to have a good balance of those three age classes, but New Mexico is already out of balance in the sense that we don’t have enough old growth. So it’s very easy to be supportive of conserving what we have left.” What’s old for one tree species might be young for another. Photograph by USFS Meanwhile, in more deciduous-dominant forests, old growth tends to offer incomplete habitat for most wildlife species, Ruffed Grouse Society president Ben Jones tells Outdoor Life. Ground cover is typically sparse in these areas, thanks to dense canopies that allow little sunlight to reach the forest floor. This provides very little ground-nesting habitat for game birds like turkeys and grouse, and even nongame birds that do nest in old-growth trees often travel to younger stands to find food. “If you talk to birders, they’re going to [age-diverse forests] to increase the number of species they’re seeing in a day,” Jones says. “Golden-winged warblers nest in really dense cover with young forest characteristics. When their young are ready to leave that nest, they take them to middle-aged forest to forage in those tree canopies. But cerulean warblers nest in that high canopy. As soon as their kids fledge, they’re taking them down to forage in the young forest cover.” Deer also have a hard time feeding in old-growth hardwood forests due to the lack of young, woody browse close to the ground, former National Deer Association senior director of policy Torin Miller tells Outdoor Life. “Deer thrive in seral and maturing forests that have a diversity of trees and other plant life and a diversity of cover. They thrive in that interface. When we get into forests that are primarily old growth monoculture with very little understory, they provide little benefit to deer specifically.” The one thing that everyone seems to agree on is that forest-dwelling wildlife, both game and nongame species, need an age-diverse mosaic of trees to survive. Immature, middle-aged, mature, and old-growth trees work together to create productive habitat for all wildlife, from songbirds to moose, Jones says. He also highlights that forests are dynamic, ever-changing ecosystems that go through cycles. A century from now, some young forests will have reached maturity while others might only be nearing middle age. Some old forests will inevitably host new growth again, especially after wildfire or other disturbance. Additionally, in a world where no single acre of forest exists free of human impact, there’s no such thing as a “hands-off” approach to management anymore. Read Next: 7 Sneaky Ways Landowners Block Access to Public Lands “How can [the USFS] play with cards that were thrown away in 1900? That’s what you’re asking the federal government to do with restrictive protections on this idea of old growth in conditions that no longer exist,” Jones says. “We don’t have roaming herds of forest bison in the east anymore, fires can’t just burn across entire landscapes for months out of the year, so we have to accept that we’re in a human-impacted environment, and we have to manage it for its best outcomes today.”   What’s Next In the near-term, the proposed action and a draft environmental impact statement should come out in May, which will initiate another 90-day public comment period, according to the Federal Register. If the GOP reclaims the White House, the odds that the amendment sees the light of day are slim. But if Democrats win, the final EIS will likely come out in January 2025.