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I just read through a portion of the Beaverhead Deerlodge National Forest (BDNF) revised plan. Among the major components of the plan is support for “vegetation management,” a euphemism for logging. The BDNF plan calls for “treating” its forests by logging to “restore” its ecological health. It has become commonplace for the Forest Service to justify logging for forest health reasons instead of timber production. We no longer log just to get the raw material for lumber and profits for timber companies. We log the forest to restore ecological health, or so the agency suggests.

Rethinking Forest Health

I just read through a portion of the Beaverhead Deerlodge National Forest (BDNF) revised plan. Among the major components of the plan is support for “vegetation management,” a euphemism for logging. The BDNF plan calls for “treating” its forests by logging to “restore” its ecological health. It has become commonplace for the Forest Service to justify logging for forest health reasons instead of timber production. We no longer log just to get the raw material for lumber and profits for timber companies. We log the forest to restore ecological health, or so the agency suggests.

I personally don’t believe that the BDNF staff is purposefully using “forest health” as an excuse to log. There is a wide-spread assumption among many forest ecologists that past forest management, including past logging, along with fire suppression, has radically altered our forests. However, the agency may be unaware of more recent research that calls into question many of these previous assumptions about forest condition and health.

Even if the assumptions about forest condition are correct, that doesn’t mean that logging can actually restore the presumed “historic range of variability.” One could restore ecological health by permitting more fires to burn, and by the use of more prescribed burning. Since this doesn’t produce profits for the timber industry, the agency is under a lot of pressure to cut trees instead of using less intrusive means like prescribed burning and wildfire as a means of restoring the presumed forest conditions. To its credit, in its Alternative 3 of the forest plan the BDNF does recommend exactly that prescription—more wildfire and prescribed burning and limited logging. Unfortunately, for the public, Alternative 3 is not selected by the agency as its preferred alternative.

The problem for anyone advocating “restoration” is that we have few references about how the forest looked a hundred years ago. There are some historic photographs that provide a valuable perspective, but whether these represent just a point in time and at a particular spot, or are characteristic of the forest as a whole is unknown. Furthermore, there is always the potential for a selective bias in the choice of photographs by the researcher seeking to find evidence for a change in forest condition and composition.

The same can be said about written accounts. When someone asserts that the forests were so open they could ride a horse through them could again reflect a bias in the observer who either selected the easiest pathway through the woods, avoiding other denser forest stands, or even a failure to note when the forests encountered were densely forested. Also there is always the chance for researcher bias that ignores some references to forest condition, in favor of descriptions that fit one’s preconceived notions about how the forest appeared.

The further back in time you go, the murkier the record. Most ecologists must rely upon reconstruction of past “historic conditions” by proxy. One popular method involves looking at fire scars on trees, and trying to determine past fire intervals. The assumption is that low intensity fires do not kill trees, but rather leave a record of their occurrence by a scar. By reading the intervals between such fire scars, researchers can reconstruct past fire occurrence and severity and make some assumptions about the historic look of these forests. However, a recent review of this method by a number of researchers has called into question the validity of many of these studies.

For instance, William Baker from the University of Wyoming and colleagues did a review of fire history studies in ponderosa pine forests and found that nearly half of them depended upon only one or two trees. Such a small sample size is suspect. Furthermore, even when a larger sample is used, there is a tendency for fire researchers to sample trees where there is an abundance of fire-scarred trees. However, such a bias in sampling may not represent the historic conditions of the forested landscape as a whole. Baker’s research suggests that the occurrence of stand replacement fires may have been greater than previously assumed, even for low elevation dry forests.

Another study done by Forest Service researcher Paul Hessburg and associates looked at the temporal patterns of eastside forests in the Cascades. He started with the assumption that past conditions would be reflected by the stand composition of the present forest. Using randomly selected air photos to review forest stand composition, he determined that there was little evidence for so called “light, low intensity” burns or “open park-like” forests in dry low elevation and moist mixed forests as presumed. Rather partial and stand replacement fires appeared to be the norm—even before fire suppression was effective and presumably created a “fuels build up.”

A third study in Colorado done by Dominick Kulakowski and his associates critiqued the Forest Service’s assumption that there was wide-spread “decline” in aspen. Kulakowski was fortunate in finding a highly detailed and accurate 1898 map of forest type and occurrence of recent burns for a portion of the Grand Mesa area of Colorado. Digitizing the map, and then comparing it to the present vegetation type for the forest, he was able to determine that relative to the late 1800s, a larger portion of the landscape was covered with aspen today than a century ago. A rash of fires near the turn of the century as a result of more favorable climatic conditions for fires (i.e. drought), as well as burning by sheep herders, miners, and other settlers contributed to an increase in aspen throughout the 20th Century. So measured against people’s recollection of aspen abundance in the recent past century, there had been a decline in aspen. But what Kulakowski’s research showed is that the current abundance of aspen was not outside of the historic range of variability—and conifer cover was actually greater a hundred years ago than today.

A fourth study of wildfires in the northern Rockies by Penny Morgan, of the University of Idaho, found one more piece of evidence that can be used to question the assumptions about “historic range of variability.” She mapped known wildfires on national forests in Idaho and western Montana from 1900 through 2003. She found the majority of all large fires occurred in just 11 fire years. These fire years coincided with extensive drought. The first six big fire years occurred prior the mid-1930s and the last five years have been since 1988—the year that much of the Yellowstone ecosystem burned. Between the 1940s through the late 1980s, moister conditions resulted in virtually no large fires in the entire region. This has major implications for our assumptions about fire suppression and fuels.

Many people use the recent past as their point of reference. In other words, people talk about the large fires we are experiencing today as compared to the 1940s, 50s, 60s and 70s and presumed that the reason has to be a consequence of greater fuels. But what is intriguing about her research is that six of the large fires occurred long before anyone can claim that fire suppression was responsible for a “fuels buildup.” No one can reasonably assert that fire suppression and fuel buildup was responsible for the huge 1910 Burn that raged across more than 3 million acres of northern Idaho and western Montana. Drought and wind drove those fires, as it has all recent big fires.

The more recent spate of large fires in the 1990s and 2000s are attributed to “fuel buildup” as a consequence of this fire suppression. However, the recent period of large fires also coincides with historically severe drought conditions across the West—the kind of climatic conditions that has always driven large blazes. Severe drought and overall warmer temperatures are also responsible for widespread beetle outbreaks. Beetle experts, however, do not see the large die-off of trees due to beetles as out of the ordinary—and many assume that such large scale beetles outbreaks have occurred in the past, again calling into question the assumption that our forests are “unhealthy.”

Temporal scale is an important factor in how we view current conditions—the longer the time frame of reference, the less current conditions seem unnatural. A study by Boise State University professor Jen Perce and colleagues looked at fire frequency and scale among ponderosa pine forests along the Payette River in Idaho. Using the geological fire history recorded by charcoal buried in soil sediment, she concluded, contrary to popular perception that low intensity blazes are the norm for low elevation dry forests, when viewed over longer time scales, climatic conditions like drought has led to significant stand replacement fires on occasion, even in ponderosa pine ecosystems.

What do all these studies and others suggest about the presumed “historic range of variability”? The message I take from these studies is that climate controls big fires and, when viewed on a landscape scale, our forests may not be out of balance as presumed. In fact our forests are very healthy and what we are seeing with both large blazes and large scale beetle outbreaks are within the “norm” for these forests if climatic conditions are taken into account. The large fires we are experiencing are “resetting” the ecological parameters of the region. There is no need to “restore” forest health—the forests are perfectly healthy and are restoring themselves—without the help of the timber industry, thank you.

Furthermore, even if it can be proved that some forests are somewhat out of “balance” that doesn’t necessarily mean that intrusive logging is necessary or can restore forest health, especially since logging has many other negative impacts that are often ignored or glossed over. These include the creation of access roads that decrease habitat security for wildlife, act as vectors to spread weeds, not to mention are a major source of sedimentation into streams (sedimentation from fires is short lived—while roads “leak” sediment for decades).

Logging operations seldom leave as many snags as naturally occur as a result of fire or beetles. Logging also removes snags which are critical to the survival of many species—for instance; more than a third of all birds in the northern Rockies are cavity nesters, not to mention use of snags by a host of other species from bats to snails. Plus, logs charred by fires take longer to decompose and last longer as a structural component in the ecosystem—with long term consequences for wildlife and nutrient flows. The presumption that logging “emulates” nature is a bunch of timber industry propaganda.

Finally, new research is calling into question the other major justifications for logging which includes the assertion that logging can stop or reduce large fire risk and/or insect outbreaks. Logging does not affect the conditions that drives large blazes namely drought, high temperatures, low humidity, and, most importantly, wind. In fact, there is even evidence to suggest that thinning the forest can substantially exacerbate these conditions leading to increased solar drying of fuels, and permitting greater penetration of wind. Even a five mile an hour increase in wind results in an exponential increase in fire spread. And removal of competing trees, leads to rapid regrowth of shrubs and smaller trees that are more flammable. The best way to reduce fire risk to communities is to fire-proof homes, not the forest.

Circling back to the BDNF plan, all of this research calls into question the Forest Service assumptions about what is “normal” for the BDNF as well as many other forests in the region. It is possible that the Forest Service assumptions about the forest conditions are accurate. On the other hand, there is more than a reasonable likelihood that our forests are well within the “historic range of variability” and need no intrusive management other than to get out of the way and allow fires, beetles, droughts, and other normal ecological processes to operate.

About George Wuerthner

George Wuerthner has published 36 books, including Wildfire: A Century of Failed Forest Policy

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  1. Thank you for that excellent review of recent research on forest health. It is easy to rationalize desired management decisions on the basis of trying to preserve healthy forests, but this forest plan is not alone. The current administration has pressured the forest service to move forward with fuel reduction programs as a part of a national strategy that has been put forward under the cover of maintaining healthy forests.

    Unfortunately, the simple rhetoric of the healthy forest initiative easily persuades people who live in fire-prone areas and are concerned about their property. Anyone who is seriously concerned about fires in the west should look at what has happened to forest service fire-fighting budgets since 2000. The current administration has consistently cut forest service fire-fighting budgets, while at the same time pushing fuel reduction. Some regions now have fewer than half the fire-fighters that they had in 2000. It is not a stretch to look at these cuts with cynicism, and see them as an effort to allow fires to cause more damage for the purpose of pushing a political agenda – namely increased logging.


  2. Holy cow what hooey.
    You talk about logging profit, Geo. Ever occurred to you that prescribed burns cost money to execute as does the stand-by to make sure the fire doesn’t escape? Who pays for that? Um, taxpayers and companies that make profits. Or do you want fire specialists to contract on barter for pemmican and berries?
    As for Penny Morgan’s time frame, 1900 to 2003 is not appropriate for a full historic reading. Let’s not forget that smallpox killed the vast majority of Indians in the Pacific NW and then the white guys killed a bunch more starting at least a century before that, leaving a huge activity gap and temporal disconnect between HISTORIC practices of burning and management before Cook/Lewis and Clark et al. Morgan needs to go back further.
    An honest reading would show that a hundred years of non-management between the end of the Indian era and the start of white settlement would go a long way towards setting up the sort of fuel conditions that led to the 1910 fire, for example.
    Furthermore, even if huge fires such as 1910 are historic, is it not more sensible to recognize that a modern society exists in the region now, with fixed, expensive infrastructure and all that jazz, and perhaps it is not rational to allow megafires? And far more rational to mechanically intervene and follow up with fires of a size and scope that are socially acceptable? Yep.
    Gosh almighty, I can’t believe this stuff.

  3. Dave:

    You raise some good point that many people would ask. Let me respond to a couple of your points.

    Sure a hundred years is a short sample, but it does show a strong correlation between drought conditions and large fire years. That same correlation exists in other studies that looked at much longer periods of time such as the one I mentioned by Jen Perce. Most of these studies look back thousands of years and depend on things like charcoal and/or pollen buried in sediments. I know of one in Yellowstone that went back 17,000 years. These studies all show that there were changes in fire frequency and scale that coincided with major climatic change. If you have a significant drought–guess what–you have a lot of big fires. Nothing earth shaking about that.

    For instance, remember how the Pueblo Indians abandoned the cliff dwellings in the Southwest–around 1100-1200 AD. Well that drought–which was huge–is recorded throughout the West by large fires in the record. For eample around this period there were huge fires that burned throughout the west slope of the Sierra Nevada in California. And these large fires burned across the landscape even though the Indians had been setting fires to the woods for centuries prior to that drought period. And interestingly the drought that the Southwest is experiencing now is considered to be as severe as that one from 1100 AD. Shouild it surprise anyone that we are having huge fires in the Southwest?

    Furthermore, if the conditions for a large fire is not sufficient to carry the blaze, you won’t burn very much acreage. That was the lesson of the interlude we have between 1940s-late 1980s. The vast majority of all fires go out without burning more than 10 acres. It is only a few very large fires that burn the vast majority of all acreage burned.

    There’s no doubt that Indians set fires, and that at times these fires flared up and became large ones, but most of the time they did not. And the question remains whether these were additive or compensatory. I.e. would we have had a similar number of large blazes without Indian ignitions. This is not unlike the same principle that wildlife agencies use to justify hunting. They argue that a certain number of deer or elk will die annually whether hunted or not. And if they do a good job of estimating this annual lost and make sure hunters do not kill any more than that number than hunter kill is compensatory not additive. But in the absence of hunters, you will still have a certain number of animals dying–particularly in harsh winters or with extended drought.

    Most ecologists who have looked closely at the issue believe that Indian burning was mostly compensatory except perhaps in the immediate area surrounding major villages or encampments.
    It doesn’t matter whether Indians set the fires or not because in many cases the fires would not burn a significant amount of land–unless it was dry enough and windy enough to carry the blaze. In which case, you don’t need Indians–lightning does the trick.

    Finally, Dave, the majority of all houses and communities at risk from fire are on private lands, not located near federal lands. If we are going to do anything to protect these homes and communities, it has to be done by local governments by zoning to keep homes out of the high fire risk areas and by private property owners who must fire proof their homes–putting on metal roofs, cleaning needles and debris from roof gutters, removing fuels like firewood adjacent to homes, and that sort of thing. Studies have shown that if adequate protective measures are put into place, most homes will survive even a stand replacement kind of blaze.

    Finally, you are missing the point of my argument–which is to say that thinning can’t and doesn’t reduce high intensity severe fires. So your last admonishment is pointless. We can’t thin our way out of this situation because it is not a fuels issue. It is being driven by global scale climatic change that is creating conditions favorable to large blazes, including hotter temperatures, longer drying season, higher winds, extended drought, and low humidity. Put all those things together in the same place–and add lightning or a match and you have an unstoppable fire.

  4. The debate about logging versus no logging on federal lands is a polarizing issue. And yes, many resource “over-kill” mistakes were made & are still occuring. A prime example is found in Colorade where in the 1970’s & 80’s Englemann spruce was clearcut at 10 thousand foot elevation–an excellent example of “timber mining”–where numerous reforestations efforts failed. Early post World War 2 federal forest management was not much different than private timber management.

    Federal forest lands encompass a wide range of diverse landscapes ranging from the high-elevation unforgiving unproductive lands of the Rocky Mountains to the more forgiving productives lands of the western Cascades in Oregon & Washington. “Industrial” federal forest management on these unforgiving landscapes was a mistake! However, in westside Oregon & Washington there are 10’s of thousands of acres of 2nd growth human regenerated productive forests –that are regulated by the Northwest Forest Plan (NFP)–that may be thinned with little or no advese effects on other resources values as all of the roads are in place & closed post logging & stabalilized by vigorous vegetative growth. In the previous 13 years, since the NWP was signed–harvest levels have been less than 10% of the net annual growth (I am not suggesting that all of the annual “interest” be harvested). Almost every other day, I hike in these westside forests, many of which have been thinned & they are beautiful & diverse forests (thinning prescriptions range from light,medium to heavy thins). I dare say that many forest visitors would claim that they are “native” forests. And the other good news is that the Old-growth & mature forests are being left intact.

    Weyerhauser (WEY) controls about 200 million acres in Canada, a large percentage that are boral forests. WEY would be content if the Forest Service never sold another stick of timber. If humans are going to continue to use wood products, then the question is where & who should provide these wood products? WEY with their Wal-Mart industrial management, the tropical forests with the loss of biological diversity or in the “forgiving” chartiable latitutes of the temperate forests where the management agency play by some environmental rules?

    Having said all of the above, I acknowledge that the primary purpose of public federal lands should be for open space, biological diversity & wild creatures. But in some select places it may be possible to have a little bit of both if we use a “light ecological foot print”.

  5. Mr. Wuerthner, Guest Commentary does not equate to literary license. Folks, don’t believe everything you read! Check the sources that are quoted. Jen Perce is actually Boise State professor Jen Pierce. I’ve checked your sources (ones that are actually spelled correctly, and even though they lack citations, I found them anyway). You’ve terribly misrepresented or twisted what was said in the Baker study and the Hessburg study (I actually talked to Dr. Hessburg regarding his study, maybe you should have as well). Regarding the Baker study, you said that nearly half of the studies of fire history depended on only one or two trees. The exact quote from the paper states, “Our review of 11 studies in the western US show that about 50% of known fires are documented by a scar on only one tree” (Baker and Ehle, 2001, p.328). This means that only one tree burned during the fire, not that the fire history was determined by one tree. The next sentence goes on to state “…we particularly suggest that the frequency of one-tree fires should be reported separately.” You then state that Baker’s research suggests that stand replacement fires may have been greater than previously assumed. What Baker actually says is the following: “In most parts of the western US there is also insufficient evidence to support the idea that mixed or high severity fires were or were not absent or rare in the pre-EuroAmerican fire regime.” Quite a different statement than what you implied.

    In response to your reply to Dave Skinner, I think you have missed the point. First, you can’t “fire-proof” a home, you make it fire-resistant by doing a few basic things, such as you suggest. Trust me, these things don’t make your home bomb-proof, it will still burn given the right set of circumstances. Second, federal land managers have many responsibilities, including managing the land for a variety of uses and benefits. One of those charges is to manage vegetation in such a manner that it is safe for the public, and another is for fire fighter safety. That doesn’t start at the private land boundary. If you’d like an example of fires that started on fed ground and wound up on private property you can look up these fire names, Sawmill Complex (MT, 2007), Egley (OR, 2007), Black Mountain (MT, 2003), Camp 32 (MT, 2005). These are just 4 that I’ve experienced first hand. You can’t just stop managing the forest because you’ve stepped across the magical wildland urban interface (WUI) boundary. Sorry, doesn’t work like that. You may have the luxury of believing that, but I have to stand next to the homeowners as the fire bears down on their property. I also have the awesome responsibility of making sure all of the kids (most under the age of 25) make it home after their assignment is completed. They don’t go home in body bags, they drive home in one piece. They get to do that because occassionally, some federal land manager somewhere miraculously gets to manage a few acres of forest outside the WUI. So, next time you have the opportunity to espouse your rhetoric, please try to do so truthfully, and in good faith. Leave your personal bias behind and report on the truth. If you can’t do that, please write it under the “Opinion” section. Thank you.