Forest Restoration or Forest Degradaton?

Note the lack of plant diversity on the left side of the path which was “treated” to “restore” the forest. Photos by George Wuerthner

These two images display a recent example of a forest “restoration” project designed to improve the “health” of a ponderosa pine forest. The area to the left of the path was recently (about a year ago) thinned and then burned. The area to the right of the trail shows what the “unhealthy” landscape was like before “restoration” occurred.

I would argue from a forest ecosystem health and biodiversity perspective, the managed landscape pictured here is degraded and less “healthy” than the right side of the pathway.

First, note that the forest left of the path is nearly uniform in species and tree size. You see little young age class trees. Other tree species that exist in the area and visible to the right side of the path like aspen, lodgepole pine, and in places, even grand fir are gone.

The “treated” side due to its more uniform species and age class is now much more vulnerable to future disease and insect outbreaks.

In addition to the loss of species diversity, there is almost no understory shrubs or other plant species on the left side (left) of the path. While the right side has a greater diversity of “habitat niches” that includes shrubs, flowers, grasses, and other plant species. All of this diversity supports a greater variety of insects, birds, small mammals, reptiles, and other wildlife.

There is a collective loss of dead wood, and even the potential for future snags and dead wood since the goal of these treatments is to preclude natural processes like bark beetles, wildfire and other natural disturbance processes from occurring.

The removal of trees by thinning has also reduced the carbon storage on the site, and as many papers extoll, this loss today is problematic and will take a long time to recover.[1]

Part of the problem is that the Forest Service and other public lands agencies have a distorted (in my view) of the actual condition of the forest. To them, the ideal state is a forest consisting of nearly pure ponderosa with little understory. No doubt, this existed in some places, but it was far less uniform as commonly asserted.

The agencies argue that frequent low severity fires kept the forest open and park-like, yet the actual evidence for this is not as strong as portrayed. There are plenty of studies that suggest that low severity fires kept the forest open and park-like, but there are also studies that present an entirely different perspective.

For instance, below is a historic photo taken in nearly the same area as the scene above, showing loggers cutting a large old-growth ponderosa pine. However, notice that in the background, there are many smaller and younger pines in the photo. I have found numerous other early photos demonstrating to one degree or another than the ponderosa pine forests were anything but open and park-like.

Several studies have come to similar conclusions. For instance, one study of the eastern Cascades where these photos were all taken found only 13.5% of dry forests were open and low density.  Shade tolerant firs were 17% dominated stands in 12% of the area, and low severity fire, which the land management agencies seek to extend over the entire landscape only occurred on 23.5% of the area with 26.5% of the forest burning in high severity blazes. Historical fire included modest-rotation(29–78years) low-severity fires with long-rotation and ( 435years) high-severity fire. [2]

Another study of dry interior forests in British Columbia also came to similar conclusions. “A complex, mixed-severity disturbance regime creates uncertainty about what represents “natural” forest conditions, or what the target conditions for restoration activities are if the objective is to “restore natural conditions.” We conclude that dry forest ecosystems in British Columbia typically experienced mixed severity disturbance regimes that included fire, bark beetles, and defoliators. Trying to “restore” these forests with applications of frequent, low-severity fire is not an ecologically sound objective over large areas.”[3]

A third study warns that the idea that low severity fires dominated our forests is inaccurate. “The consensus … traditional reference conditions of low-severity fire regimes are inaccurate for most forests of western North America. Instead, most forests appear to have been characterized by mixed-severity fire that included ecologically significant amounts of weather-driven, high-severity fire.”[4]

Similarly, Hessburg using air photos to detect forest stand composition and density east of the Cascades, concluded: “Evidence for low severity fires as the primary influence, or of abundant old park-like patches, was lacking in both the dry and moist mixed conifer forests. The relatively low abundance of old, park-like or similar forest patches, high abundance of young and intermediate-aged patches, and wide-spread evidence of partial stand and stand-replacing fire suggested that variable fire severity and non-equilibrium patch dynamics were primarily at work.”[5]

I can’t explain why there are different interpretations of the historical conditions, but one source of conflict is the use of fire scar studies to recreate the forest stand and fire histories of these forests. Some authorities believe there are inherent methodical biases in fire scar studies. [6]

Also, keep in mind that by happy coincidence, short fire rotations, and the paradigm that dry forests were almost uniformly open, park-like stands favors logging. Given the Industrial Forestry Paradigm that dominates forestry schools and thus, foresters working for public land management agencies, it is not surprising that they support some “management.” If there were no logging, there would be no jobs for foresters. That has to influence how you see the need for manipulation of the forest ecosystem.

As the writer, Upton Sinclair noted: “It is difficult to get a man to understand something when his salary depends on his not understanding it.”

In any event, I would posit that most of the “vegetation treatments” (a euphemism for logging) are creating conditions that did not exist or were far less common than assumed. It is important to note that what agencies call “healthy forests” is not the same as “healthy forest ecosystems. It is biased towards preserving green trees, which are fodder for timber production. These management activities, particularly the removal of trees, are creating a deficit in our forests for carbon, for biomass, for ecological processes that maintain healthy forest ecosystems.

[1] B.E. Law ⇑, R.H. Waring … Carbon implications of current and future effects of drought, fire and management on Pacific Northwest forests Forest Ecology and Management Volume 355, 1 November 2015, Pages 4-14


[2] Baker, W.L. Implications of spatially extensive historical data from surveys for restoring dry forests of Oregon’s eastern Cascades. Ecosphere March 2012 v Volume 3(3) v Article 23


[3] Walt Klenner, Russ Walton, Andre’ Arsenault, and Laurie Kremsater. Dry forests in the Southern Interior of British Columbia: Historic disturbances and implications for restoration and management. Forest Ecology and Management 256 (2008) 1711–1722


[4] Examining Historical and Current Mixed-Severity Fire Regimes in Ponderosa Pine and Mixed-Conifer Forests of Western North America  C. Odion, Chad T. Hanson, Andre’ Arsenault, William L. Baker, Dominick A. DellaSala, Richard L. Hutto, Walt Klenner, Max A. Moritz, Rosemary L. Sherriff, Thomas T. Veblen, Mark A. Williams


[5] Hessburg et al.  Re-examining fire severity relations in pre-management era mixed conifer forests: inferences from landscape patterns of forest structure Landscape Ecology 2007


[6] Wuerthner. G. Wildlife News.


  1. Sarah Hyden Avatar

    This is exactly what we are seeing in New Mexico — decades later thinned and periodically burned forests look barren, unhealthy and dry, with very little or no understory. Frankenforests. I can’t understand how they can be seen as “healthy” in any way. Untreated forests often look fairly healthy. The evidence that is presented in this article supports what we can see plainly with our eyes — that forests treated with extensive thinning and burning are not in any way emulating natural or historic forests.

  2. Nuri Benet-Pierce Avatar

    I was both surprised and dismayed at seeing similar “restored” pine forests in California these past late summer. I study Chenopodium, which you could call an obscure genus of plants, if it not were that we know Chenopodium quinoa well, now that it is a popular pseudo-grain.

    Chenopodium is very diverse in the Western United States, and many of the native species grow in pine forests, in sagebrush and in more desert –like habitats.
    They play an important role in the ecosystem as birds eat their seeds and beetles and bugs lay their eggs on it. It is a heavy seeder but once it is extirpated, because it is an annual plant, once the plant community is very well established it has difficulty getting a foothold.

    It loves to grow in disturbed habitats so roadsides are (were) ideal to find them. However, to my dismay, these newly restored forests completely lacked the understory and Chenopodium is almost gone. In its place a new set of invasive weeds were taking its place in some areas.
    Is there anything that can be done? I consider this a tragedy!

  3. Beeline Avatar

    Several related notes:

    Australian National University Professor David Lindenmayer recently stated ( not long after the huge fires in Australia) ” On the event of wildfires, land managers must avoid practices such as ‘salvage logging’ or logging burnt forests which severely reduces recovery of a forest”.

    Second note:

    Many years ago the forest service started justifying burning forest slash and other down material because it released nutrients. This partial truth provided them with an excuse to increase timber harvest and slash burning with little consideration for the natural nutrient cycle.

    A report from Science Daily 28 May 2020 sheds more light on the subject. It was found by a team of researchers that streams near northern forest burn sites showed increased levels of inorganic nitrogen. Inorganic nitrogen is basically a simple mix of nitrates, and nitrates contribute to aquatic plant growth. Levels of inorganic nitrogen remained high for around 10 years. However, organic forms of nitrogen which are required by terrestrial vegetation and for forest regrowth remained quite low for nearly 50 years after a burn.

    In a nutshell organic matter must be left behind to properly feed the nutrient cycle. Otherwise it won’t be possible to have healthy forest.

    The same principle can be seen on range lands that are grazed by cattle. On heavily grazed annual range where only 100 lbs/acre of mulch is left behind there will be limited production of next years crop. Less than 500 lbs/acre. If 500 to 750 lbs/acre of mulch is left behind after grazing, the next years production shoots up to 1000 lbs/acre or higher.

    By attempting to speed up/increase harvest, our agencies are actually reducing the production on public forest and range land. They do not increase the health of public land- they impoverish it.

  4. Larry Keeney Avatar
    Larry Keeney

    Like this week of Black Lives Matter protests things need to change. In the natural resource agencies the word ‘management’ needs changing. We don’t manage nature. We destroy it, alter it,sell it or give it away but we don’t manage it. We manage money and cows but not nature. Who ‘managed’ nature 50 million years ago that gave us the biodiversity we can still find in the Tongas or Death Valley and pristine coral reefs? What do we have after natural ecosystems are’managed’, less diversity and someone who is richer than when nature was in charge.

    We need to name these agencies what they are, Bureau of Land Manipulation and Forest Manipulation Service for starters and end with Fish and Game Farming Department.

  5. Sarah Hyden Avatar
    Sarah Hyden

    This is exactly what we are seeing in the ponderosa and dry mixed conifer of Santa Fe National Forest. Thinned and burned areas from two decades ago are not recovering and the understory is not returning except for some scattered grasses that manage to come back between prescribed fire treatments. I don’t know how anyone can call this condition healthy forest. It is obvious these treatment regimens are not emulating a natural or historical fire regime. Historical forests were abundantly alive, not frankenforests, as are being created today by the US Forest Service and their partners.

  6. Lura Brookins Avatar

    Yes, let Nature “manage” nature! Then we can observe and learn.


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