Logging Road Impacts

Logging roads are a major negative impact on ecosystems. Photo George Wuerthner 

The latest attempt by the Forest Service to make timber cutting palatable is using the terms “temporary” and “closed” to describe logging roads. The implied message is that road impacts are magically eliminated if they are temporary or closed. Roads, temporary, “closed,” or permanent, are among the most significant effects on forest ecosystems. (For a good review of road impacts, see Trombulak and Frissell.)

An ineffective “road closure” on the Custer Gallatin National Forest, Montana. Photo George Wuerthner 

The Forest Service has at least 400,000 miles of roads on the lands it administers, and these roads have a significant environmental collateral impact associated with logging and other resource exploitation.

A “closed” road still provides access to hunters, ATV, dirt bikes and mounain bikes. Photo George Wuerthner 

However, “temporary” roads and so-called “closed” roads are not the same as no road. Even years ago, when I was a wildlife student at the U of Montana, research showed that even “closed” roads had a passive negative impact on wildlife because people used them.

Where ATVS have driven around a “closed” road gate. Beaverhead Deerlodge NF, Montana. Photo George Wuerthner 

Given the steep terrain in western Montana, I often hunted by walking on the “so-called” closed roads. And, of course, dirt bikes, ATVs, and mountain bikes regularly use them.

A “reclaimed” logging road on the Custer Gallatin National Forest, Montana. A truly reclaimed road would restore the slope and lens, rip up compacted soil profile, and replant the natural vegetation. Photo George Wuerthner 

Worse for the ecosystem, these “closed” roads are seldom rehabilitated to restore the road lens and slope. Creating logging roads and skid trails increases soil density, and reduces water infiltration. Soil compaction along logging roads can last for up to 100 years. Roads cut the subsurface flow of water, which often winds up on the compacted roadbed where it gathers sediment that flows into streams, harming aquatic life.

Erosion and sedimentation from logging road, Rock Creek drainage, Beaverhead Deerlodge NF, Montana. Photo George Wuerthner 

Numerous studies have shown that roads are a chronic source of sedimentation into streams. Even the sediment after a fire usually only lasts a few years. Sedimentation from logging roads is why sensitive species like bull trout have declined across much of its range.

Logging roads also displace sensitive wildlife (i.e., elk, bears, and other wildlife) that avoid human intrusions. Even the noise of trucks, ATVs, and logging machinery can impact wildlife.

Weeds growing along logging road. Logging roads are a major vector for the spread of weeds. Photo George Wuerthner 

Roads are also a major source of weed spread. Some of these weedy species, like cheatgrass, increase wildfire, and other species, like spotted knapweed, compete with native plants.

The construction of roads removes biomass and reduces carbon storage in the area.

Another critical factor today is that nearly all human ignitions occur near roads. One study found that 90% of all wildfires happened within a half mile of a road.

The miles and miles of FS roads are one of the factors in the growth of wildfires since most of these human ignitions occur when natural ignitions from lightning are not happening. . Human ignitions started 76% of the wildfires that destroyed structures, and those fires tended to be in flammable areas where homes, commercial structures and outbuildings are increasingly common.

Human ignitions, facilitated by access along logging roads, lengthen the fire season, contributing to more blazes.

By opening the forest , logging roads can lead to drier conditions and funnels of wind along the corridor, which enhance fire spread.

A fully reclaimed logging road in Redwood National Park. Photo George Wuerthner 

To fully reclaim a road is more than putting up a gate to block vehicle travel. It requires ripping up the roadbed to remove the compacted soil layers. The side slope soil has to be put back on the site and reshaped to restore subsurface and surface water flow. Culverts need to be removed. Stream channels should be entirely restructured and reconstituted. Vegetation needs to be planted—and grass seed is not enough, especially if the area once supported forest. Logs, rocks, and other natural structures must be returned to the slope.

Essentially, these ecological costs of logging roads are a subsidy to the timber industry that is not internalized. If they were included in the cost of a timber sale, we would have a lot less logging on public lands.

Home hardening is by far the most effective means of reducing wildfire home losses.


  1. Maggie Frazier Avatar
    Maggie Frazier

    Seems to me the effort, expense & habitat damage caused by chaining, logging efforts to make areas more “habitable” for livestock – would be much better served in putting logging roads back to their natural state.
    Seems simple enough to me.
    I dont have the knowledge or experience of Mr. Wuerthner or others who comment here – but how hard is it to understand that – IF you want to!!

    1. Jeff Hoffman Avatar

      Correct! It’s far more about attitude toward the natural environment than it is about a few facts.

  2. Ed Loosli Avatar
    Ed Loosli

    Court halts logging project in Montana’s Kootenai Nat. Forest over threats to grizzly bears and to the climate from logging old growth trees.


    1. Ida Lupine Avatar
      Ida Lupine


      1. Ida Lupine Avatar
        Ida Lupine

        I should have written:

        Good. You’ve got to love and thank Judge Molloy! 🙂

  3. Mary Avatar

    For fire safety, let’s get timber sale rules updated to include full restoration of logging roads.

  4. Sarah Avatar

    To even begin to close unneeded forest roads would take law enforcement, because forest users will use them almost no matter what kind of barricades are put there. They will move them, or cut through fences. For the three northern New Mexico national forests, we normally have one law enforcement officer. That officer can’t possibly monitor whether closed forest roads are being used over half a state.

    The term temporary roads is almost insulting, because we all know there is virtually no such thing. If the Forest Service starts a road the public will finish it and keep it going indefinitely.

  5. Ida Lupine Avatar
    Ida Lupine

    “The project would have included logging in areas with trees ranging from 100-180 years old. Ted Zukoski, with the Center for Biological Diversity, says Molloy’s ruling means the U.S. Forest Service cannot overlook the impacts of climate change when cutting these older trees or clear-cutting swaths of forest.”

    We can’t rave about climate change and then in practice do things like this. It’s not that I don’t believe in climate change, I do, and of course 8 billion+ humans on this planet have and will leave their indelible mark.

    But what I don’t like is to have it treated like an empty issue and ‘pop-culturized’ by the media, while we go right along with doing the same things we always have.

    And I hope we don’t think that putting logging forests, and old growth at that.

    Thanks for posting this decision.

    1. Ida Lupine Avatar
      Ida Lupine

      oops, something went wrong, that should have read:

      “I hope we don’t think that putting up wind turbines and solar panels is going to offset logging our forests, and old growth at that.

      1. Mary Avatar

        It’s worth noting, old growth forests are not tree farms, and we should be sure to let decision-makers know.

        A lot of tree harvesting professionals may not– yet! know that old growth trees store the

        Here’s Prof. Simard talking about her seminal research in the forests of western N America–

        That research, backed up by other forestry professionals, found that older trees support younger ones, trees in a forest do not compete– they share resources with each other.
        Finding the Mother Tree

        We can support tree farms– but we can not support treating the old trees and damaging their surrounding habitat– as an economic necessity.

        1. Jeff Hoffman Avatar
          Jeff Hoffman

          Tree farms replace native forests. We should not at all support tree farms. Humans need to learn to live a lot more naturally, and to stop harmfully manipulating the natural world, and this includes killing ANY native trees for any reason.

          1. Mary Avatar

            Agreed. With some 3% or so native forests left– we can start by restoring some that were taken.

            However, toilet paper and tissues are not going away.

            None of that will stop if we don’t get a handle on our own, 8+ billion and counting numbers…

        2. Nancy Avatar

          Someone else, weighing in on old trees, Mary, and the “poaching” going on now, that most of us aren’t even aware of when it comes to old growth forests:

  6. Jerry Thiessen Avatar
    Jerry Thiessen

    Roads are a scourge on forest wildlife and ecology. Tons of data supports that fact but I’m not sure that ripping out old roads with giant equipment and reexposing sediment to downslope movement and stream pollution is the best way to go. Removing culverts, reshaping where necessary, and totally stopping motorized travel are essential elements of rehab. Planting trees in the old roadbed gives the forest a head start. After that,forest litter accumulates with time to a more natural mix of native plants. Alien weeds are a problem but won’t be controlled by reexposing raw soil to the environment.

    1. Mary Avatar


      And since cheatgrass acts as a wick for super-fires– an annually renewed invasive that burns faster, hotter, more often than native vegetation–

      Perhaps logging contracts can have built in funding and work hours set aside for full restoration of any logging roads.

    2. Jeff Hoffman Avatar

      If the roads are unpaved, giant equipment is not needed to close them. Just plant native trees and other plants on the roads, add some soil if necessary. But for paved roads, the pavement needs to be removed. Don’t know what equipment removing them requires, but they need to be removed by whatever means necessary. Roads fragment habitat, and many species won’t cross them.

    3. Maggie Frazier Avatar
      Maggie Frazier

      I hope my comment didnt give the impression that logging roads should be “ripped out”. I think theres already far too much giant equipment used in these habitats. Unnecessary equipment. I agree that removing culverts etc sure would be a good idea – maybe using manpower labor rather than machines! If there is a will to correct some of the environmental damage – then there is a way!

  7. Cindy Kreiman Avatar
    Cindy Kreiman

    We need to stop making roads cutting frees encroaching, destroying and invading lands that belong to Nature, Wildlife and life itself. At some point we need to take a good look at ourselves and what we have done and continue to do and realize it will come back to us,it will affect us just as much as all other lives. We are not immune to being destroyed and we are doing that to ourselves, no one else to blame….


George Wuerthner is an ecologist and writer who has published 38 books on various topics related to environmental and natural history. He has visited over 400 designated wilderness areas and over 200 national park units.

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George Wuerthner