Tuesday, June 30, 2009
Beetle hysteria has raised its head again, and I am not talking about the Fab four. A prominent article in the New York Times titled “Tiny Beetle Adds New Dynamic to Forest Fire Control Efforts” quotes many foresters and others who suggest that beetle-kill trees across the West will create larger wildfires and by implications are “destroying” our forests.
For instance, Montana’s State Forester Bob Harrington said as much at conference recently, as in the article. While it may seem “intuitively obvious” that dead trees will lead to more fires, there is little scientific evidence to support the contention that beetle-killed trees substantially increases risk of large blazes. In fact, there is evidence to suggest otherwise.
At the heart of this and many other media reports are flawed assumptions about fires, what constitutes a healthy forest, and the options available to humans in face of natural processes that are inconvenient and get in the way of our designs.
For instance, one study in Alaska’s Kenai Peninsula looked at 2,500 years of bark beetle events, and wildfires and could find little correlation between the two. Similarly a study that looked at burn patterns of the 1988 Yellowstone fires found little evidence that recent bark beetle outbreaks had substantially increased fire spread in the Park (though an earlier beetle event did seem to increase fire spread slightly—more on why below).
In fact dead trees don’t automatically lead to more fires since climate/weather events, not fuels, largely controls large blazes. If the climate/weather isn’t conducive for fire spread, it doesn’t much matter how much dead wood you have piled up, you won’t get a large fire. As an extreme example, think of all the dead wood lying around on the ground in old growth west coast rainforests—lots of fuel, but few fires—because it’s too wet to burn. But it’s even more complex than that generalization.
First to understand why beetle-killed trees don’t necessarily lead to large fires, one needs to know more about how bark beetles affect forests. Younger trees are not killed by beetles, and remain in the forest to fill the void created by the death of more mature trees. In effect bark beetles “thin” the forest but typically there are still lots of trees growing on the site--some large mature trees and a lot of smaller ones. So the “forest” is not destroyed, nor does it “disappear” as may be implied from the hysterical statements coming from logging proponents, and others connected to the timber industry.
Furthermore, mature trees are not hapless victims. When a bark beetle attempts to bore into the tree, the tree uses its sap to push out the beetle and any eggs. A strong healthy tree with sufficient resources can often flush beetles out. It is not unlike the ability of a healthy moose to deter a wolf attack. Indeed, wolves are seldom successful in taking down a healthy mature moose unless circumstances give them the upper hand. Trees under stress from drought or damage from other causes are more vulnerable, just as a moose suffering from lower nutrient as a result of drought is more likely to be killed by wolves. So while beetles do kill trees, they aren’t able to “destroy the forest”—many smaller trees and even a significant number of mature trees survive.
Since bark beetles tend to focus on larger trees and not all trees are killed, this has important implications for fire risk. Fine fuels—not large snags—are the prime ingredient for sustained fire. So what you have after a major beetle outbreak is a lot of standing upright big boles. You can’t get big logs to burn unless you have fine fuels beneath them to sustain the heating process. That is why one uses small kindling and other fine fuels to start a campfire and must continuously feed small wood under the bigger logs to keep the fire going. Assuming you have the right conditions for a fire in the first place, a forest fire will spread more rapidly and with greater intensity in a totally green forest than a sea of dead boles, in part because the green forest possesses a lot more fine fuels in the form of resin-filled needles and small branches.
Furthermore, tree flammability is not constant, but varies over time. It is highest immediately after beetles kill the tree, and brown needles and small branches remain on the tree. However, after a winter or two, the needles and smaller branches are knocked from the trees and their flammability goes way down since the remaining upright snags are actually quite resistant to flames. It is generally only after understory trees released by the death of more mature canopy trees grow taller and provide a ladder into the canopy that fire hazard again increases. These ladder fuels, along with any dead snags that have toppled to the ground, can potentially lead to greater fire hazard. But this process takes decades. Thus the immediate threat from bug killed trees is not likely to be great, especially if the climate/weather is wet.
Of course, if you have the right conditions for a big burn, the dead trees will burn, but typically not at any greater potential than a forest of green trees. Green trees, after all, with their flammable resins in needles and branches are highly combustible under extreme drought and high temperatures. Indeed, there is some evidence to suggest that green trees will burn even hotter and with greater intensity than say a dead snag.
Potential is not the same as absolute. Most lodgepole pine, the primary species attacked by beetles in the Rockies, tend to be found at moister, higher elevations which simply do not dry out enough to burn well in most years. That is why lodgepole pine forests typically have long rotations between burns—on the order of hundreds of years in some places. Thus the presence of dead trees does not necessarily lead to fires. The probability that any particular bug-killed stand will be ignited by lightning or humans during the few years out of a hundred when they are dry enough to carry a large blaze is actually quite small. So even if there is a lot of dead wood on the ground, that doesn’t mean you will have large blazes. Probability is important—and the probability is low.
Even more importantly the news media often neglects to educate the public about the ecological value of bark beetles as “ecosystem engineers”. Beetles are essential to maintaining biodiversity in our forests. One study of bark beetles in Europe found that bark beetles created habitat for a wide array of other insect species, including many pollinating bees and warps, whose numbers increased in the forest gaps created by bark beetles.
But it’s not just insects that increase as a consequence of beetle kill. Dead trees created by bark beetles are used by cavity nesting birds, bats, and many small mammals. When dead trees fall to the ground, they provide hiding cover for insects, mammals, and amphibians from salamanders to frogs. Dead trees that fall into streams create aquatic habitat for fish. Of course dead trees are utilized by fungi, lichens, and as a source of new nutrients for new plant growth. Thus if we grant that an increase in biodiversity is important to the long term forest health, beetles are actually a sign of “forest health”.
Even the way a tree dies radically affects its future decay trajectory. A tree killed by wildfire, for instance, decays much slower than one killed by beetles. Beetles by penetrating the outer bark of a tree permit other organisms including other insects as well as fungi to enter the tree and begin the decay process. While fire killed trees, charred black by fire, are more resistant to decay. Bark beetles in addition to wildfire, wind throw and other natural events all contribute to different future forest dynamics.
The current spate of beetle outbreaks and dead trees in and of themselves is nothing to be alarmed about. However, there is another reason to be concerned. The current beetle “outbreak” may be harbinger of climate change that may radically alter future forest ecosystems. Warmer temperatures due to climate change may be responsible for the expansion of bark beetle outbreaks in the West (though there is historic evidence to suggest that past outbreaks affected as many or even more acres than what we see today). Cold winter temperatures, for instance, tend to kill beetles and keep their numbers under control.
Warmer temperatures not only increase the survivorship of beetles, but permit beetles to attack trees at higher elevation than in the past, and this has led to the death of many whitebark pine which, though occasionally attacked by beetles, usually are not affected to any great degree by bark beetles due to the whitebark pine’s preference for high cold elevations.
Yes bark beetles are killing many trees, but that necessarily won’t lead to large fires. Even if it did, there’s not much humans can do directly to forests to influence fire risk, except to begin reducing human causes of climatic change. Logging the forest will not significantly influence fire spread, and removal of dead trees has many negative impacts on forest ecosystems. Logging itself creates many additional environmental impacts such as greater sedimentation of streams, invasion of weeds, and so on that are far too often ignored by proponents of active forest management.
Nor can humans have much influence on the spread of beetles. To effectively reduce forest susceptibility to bark beetles, 50-80% of the trees have to be removed. Since that is typically as much, or in many cases even more trees than are killed by bark beetles, such let’s cut the trees to save them seems unwarranted. Plus there is no guarantee that the particular stand of trees that are treated with thinning are the same ones that will be attacked by beetles.
As far as community protection is concerned, it is far more cost effective to reduce flammability of homes than to attempt to reduce the flammability of forests. Focus fire risk reduction in and near homes, not out in the backcountry.
The important take home message is that we need a paradigm shift in our response to bark beetles. We cannot significantly influence large scale ecological processes like bark beetles and wildfire. Rather we must adapt ourselves and communities to learn to live with them. If climate change is ultimately the reason for changing tree vulnerability to beetles, than we should deal with reducing human sources of green house gases.
Secondly, beetles are not destroying our forests, rather are creating new ecological opportunities, increasing biodiversity, and creating greater ecosystem health.
Sunday, June 21, 2009
TESTIMONY OF GEORGE WUERTHNER June 19, 2009
Representative Raul Grijalva, Chair
House Subcommittee on National Parks, Forests and Public Lands
Representative Grace Napolitano, Chair
House Subcommittee on Water and Power
Joint Oversight Hearing on "Mountain Pine Beetle: Strategies for Protecting the West”
Dear Representatives Napolitano and Grijalva:
Thank you for allowing me to provide testimony on the mountain pine beetle issues in the western United States. I believe I can bring an ecological perspective to the concerns and I ask that my comments be submitted as part of the hearing record.
First let me introduce myself. I have lived in a number of western states either for school or work. These states include Wyoming, California, Idaho, Montana, Alaska, and Oregon and have visited many others in the course of my work which I will discuss below.
I attended the U of Montana in Missoula for my undergraduate degrees in wildlife and botany, and was enrolled in three separate graduate programs at Montana State University, University of California, Santa Cruz and the U of Oregon.
For quite a few years after leaving academia, I earned my living as a writer and photographer and have published 34 books covering national parks, conservation history, geography, environmental and ecological topics. Two of particular relevance to the topic of pine beetles and wildfire issues are Yellowstone—the Fires of Change, and Wildfire: A Century of Failed Forest Policy.
In researching these books I have had the luxury of traveling extensively across the West to view the aftermath of major wildfires, and the time to read the latest scientific literature related to wildfires, beetles, and other issues. Indeed, at one time or another I have visited every national forest in the West, which, along with my ecological training, gives me a geographical perspective few can provide.
I will address some of the common misconceptions and provide some alternative viewpoints on specific issues. I encourage you to view a recent powerpoint talk I gave that covers many of the major points I will make below.
I would also encourage you to review the paper by Romme el al.
Recent Forest Insect Outbreaks and Fire Risk in Colorado Forests: A Brief Synthesis of Relevant Research for a good overview of beetle ecology and relationship to wildfire. http://18.104.22.168/search?q=cache:JDj5CMoOWjoJ:www.cfri.colostate.edu/docs/cfri_insect.pdf+pine+beetles+romme+Colorado&cd=19&hl=en&ct=clnk&gl=us
I want to highlight a few of their major points here.
First they conclude that: “There is no evidence to support the idea that current levels of bark beetle or defoliator activity are unnaturally high. Similar outbreaks have occurred in the past.”
Second, the idea that dense stands of trees are a consequence of fire suppression is very dependent on the forest type. Higher elevation forests are naturally dense and have not changed significantly due to fire suppression or any other human activities.
Finally, their concluding remarks are worth keeping in mind. They state: “Although it is widely believed that insect outbreaks set the stage for severe forest fires, the few scientific studies that support this idea report a very small effect, and other studies have found no relationship between insect outbreaks and subsequent fire activity.”
And they go on to say … bark beetle outbreaks actually may reduce fire risk in some lodgepole pine forests once the dead needles fall from the trees.”
I will elaborate on all these points below.
Let me start my testimony by suggesting that many of the phrases and words used to describe natural ecological processes like episodic pine beetle events and wildfire are pejorative in tone. We heard a lot of people testifying in this hearing that pine beetles were destroying the forests and/or wildfires were catastrophic and so forth. From the perspective of human values, these words might resonate—certainly if a wildfire burns down someone’s home, it is a devastating experience. However, it is less clear that these terms are appropriate in describing natural ecological events like pine beetle events or large blazes. (See my comments on this in Wildfire: A Century of Failed Forest Policy or Rocca and Romme (2009).
Indeed, pine beetle events, wildfire, and killing droughts are natural ecological processes that are critical to the maintenance of forest ecosystems. To the degree possible, I try to avoid using words with regards to wildfire and beetles such as “destroyed”, “damaged” “unhealthy”, and so on.
As we shall see later in my testimony, dead trees may be more important to the long term “health” and sustainability of forest ecosystems than live trees. There are even some ecologists who believe we do not have enough dead trees to sustain forest ecosystems.
As many of those testifying alluded to, climate/weather may be a big factor in current beetle population increases as well as wildfire size and occurrence (Meyer and Pierce 2003; Whitlock 2004, Westerling, et. al. 2006, Heyerdahl,E. et al. 2008). As has been noted warm winters tends to increase survival of pine beetle allowing their populations to grow rapidly.
Warmer summer temperatures, combined with drought, increases tree vulnerability to beetles, and is a key ingredient in wildfire spread. The importance of climate and large scale oceanic influences on wildfire are obvious from this graph below has the Pacific Decadal Oscillation superimposed over the acreage burned annually by wildfire.
Source: Dave Peterson USFS
This graph shows how the Pacific Decadal Oscillation may have affected wildfires. Cool, moist weather in the 1945s-1980s would have limited fire ignitions and spread. This is the same period that we attribute fuel build up to “effective” fire suppression. But it’s just possible that the conditions were not favorable for fire spread, thus the influence of fire suppression may be exaggerated and overrated.
There several messages to take home from this graph.
The first is when it’s cool and moist, fires don’t spread. It doesn’t matter how much fuel you have, you still won’t get a big blaze. Most fires go out without burning more than a few acres. To illustrate this point, think about the rainforests found in the Coast Ranges of Oregon and Washington. There’s more “fuel” sitting on the ground in those forests than you will find any place in the Rockies but in most years there are no fires. Why? Because the forest is too wet and cool to burn well.
Take home point: Fuels alone do not necessarily lead to massive fires. Thus the fact that pine beetles are killing lots of trees does not, in itself, portend large wildfires.
The key ingredients in all large fires are long term drought, low humidity, high temperatures and most importantly wind. In the absence of these factors, you might get an ignition, but the fire will remain small and likely go out quickly. The mere presence of fuel does not imply that you will have a major wildfire. Since the probability of these climatic/weather factors converging on the same geographic point at the same time is very low, not surprisingly large blazes (pejoratively called catastrophic) are relatively infrequent and rare events.
The interpretation that fire suppression is largely responsible for “dense” tree stands is also being challenged. First in some tree species like lodgepole pine and high elevation spruce-fir forests, recruitment after fires and/or insects tends to create even aged dense stands. Thus it is not “fire suppression” that has created dense forests and these forests are not “overstocked” but display the exact kind of tree age and density that occurred historically.
But more intriguing idea that is getting some traction is that periodic moist, cool periods may also lead to high rates of seedling germination and survival leading to episodic events of tree establishment. In other words, favorable weather for tree survival may be as responsible for “dense” tree stands in some tree species such as ponderosa pine as much as fire suppression (Brown and Wu 2005).
BEETLE KILL DOES NOT NECESSARILY LEAD TO GREATER FIRE SEVERITY OR SPREAD.
A common misconception is that dead trees will increase fire hazard. For instance, one study on beetles and wildfire occurrence that span the last 2500 years, found little correlation between wildfire and beetle events (Berg and Anderson 2006).
Another study (Lynch 2006) in Yellowstone on recently beetle killed lodgepole pine found that susceptibility to wildfire was not necessarily increased, though an earlier beetle event did appear to increase fire occurrence (the reasons are not due to dead trees, however, as I will explain below). Similar findings were reported for subalpine forests elsewhere in the Rockies (Bebi et al. 2003, Schoennagel et al. 2004, Biger et al 2005).
After a beetle event, there appears to be significant variability in fire susceptibility of forests that varies over time—assuming you have the prerequisite drought, wind, and low humidity that drives all large fire. Flammability is increased immediately after a tree is killed by beetles in what is known as the “red needle phase.” However, after the passage of one or two winters and the needles and small branches fall from the tree, the flammability goes way down. Thus if there is no ignition in those first few years (which as we noted earlier is very unlikely), the fire risk is significantly reduced.
It is only after the passage of several decades that susceptibility to fire increases, but not as much due to fuels, but as a result of rapid growth of small trees and shrubs that occurs after the forest canopy is opened by beetles. These small trees provide a ladder for flames to reach up into the forest canopy.
Nevertheless, even this period passes as the forest canopy once again closes, reducing forest fire susceptibility for many decades, even hundreds of years. (See Romme et al. 2006)
DEAD TREES DON’T BURN WELL
Another misconception held by many is that dead trees will increase fire hazard. As explained earlier fire hazard varies over time. But it is fine fuels that carry fires, not large boles. We see that easily after a wildfire. What do you see? Lots of snags. The needles and small branches burn off, but the core tree boles remain. One intuitively understands this from camping. When you try to start a campfire, you gather up “kindling” and small branches to start a fire. If you pile up a bunch of large logs and try to light it, you will likely get nothing for your efforts.
So while dead trees may not increase fire hazard, in reality the presence of green trees may. So in effect the large occurrence of dead trees killed by beetles may actually be reducing the fire hazard for nearby communities.
UNDER SOME CONDITIONS GREEN TREES DO BURN WELL
Let me explain. Green trees are often more flammable than dead trees, especially compared to dead trees (snags) where the needles and small branches are gone. The reason has to do with fine fuels. A living tree has a lot of fine fuels in the form of needles, branches, etc., plus at least for many conifer species, the needles and branches are full of flammable resins. Under drought conditions the internal moisture of these living trees often drops to very low levels. In Yellowstone NP during the 1988 fires, the internal moisture content of green trees was reported to drop below that of kiln dried lumber. Under such conditions of low humidity, drought, and high temperatures, combined with high winds, some green trees with high resin content will burn exceedingly well. (Bunting 1983, Perry 1995)
THINNING AND LOGGING MAY NOT REDUCE FIRE HAZARD
There’s a natural assumption that logging, by removing fuels, will reduce fire hazard. However, the evidence for this is inconclusive at best. There are examples of where thinning appears to have slowed the spread of fires and increased the ability of trees to survive stresses like beetles, drought, and fire (Youngblood et al. 2009), and in some cases reduce fire severity, but fires were not necessarily stopped or controlled as a result of fuel treatments (Pollet and Omi. 2002).
There as many examples of fires racing through previously thinned or logged stands. Indeed, logging can actually increase the likelihood of fire spread by opening up the forest to increased solar radiation and drying. Wind penetration is also increased by thinning. Wind increases drying of fuels, and pushes flames through a forest.
Though fuel treatments may appear to reduce fire spread and severity under “moderate” fire conditions, under severe climatic/weather conditions, particularly with high winds, fuel treatments do not appear to have significant influence on fire spread.
Fuel treatments could even create a false sense of security, much as the levees in New Orleans created for residents. Just as the Mississippi levees were breached when confronted by a category five hurricane, forests with fuel reduction treatments are often “breached” by wildfire under the equivalent of a “hurricane” force wildfire with high winds, low humidity and high temperatures.
DENSE TREE STANDS HAVE SOME VALUES AS WELL
The presumption that thinning forests is always a positive influence on forest ecosystems can be challenged as well. Trees growing under dense conditions tend to have tighter growth rings and are by nature stronger, and more resistant to decay as well. This has important implications for the long term biomass residency time of dead and down logs on the forest floor. Also there is some evidence to suggest that dense forests may inhibit fires due to greater shade and moisture—for instance on the Biscuit Fire in Oregon, dense forest stands tended to burn less severely than more open stands.
FUEL TREATMENTS CAN INCREASE FIRE HAZARD
Thinning, by creating more surface fuels, can increase fire hazard. Unless such surface fuels are removed, a subsequent fire can burn more severely. Thinning, combined with prescribed burning to remove surface fuels is often the most effective treatment, however, burning often does not follow thinning projects.
Furthermore, the effectiveness any fuel reduction treatment declines over time. Typically within 10-20 years, fuel loadings often approach pre treatment levels, thus thinning requires continual maintenance. This is one reason why thinning, if it is used, should be focused on the areas immediately adjacent to communities. Unfortunately, most FS fuel treatments so far are located well beyond that zone. According to a recent review of 44,000 fuel treatments implemented under the National Fire Plan only 3% were in the Wildlands Urban Interface (Schoennagel et al. 2009).
DEAD TREES ECOLOGICALLY IMPORTANT
One of the assumptions implicit in much of the angst over beetle events are the fact that many believe beetles “destroys” the forest. In reality, dead trees may be more important to forest ecosystems than live trees. Dead trees are biological legacies that are critical to ecosystem function. For a short overview see my articles in Forest Magazine Let us praise and keep the dead. http://www.fseee.org/forestmag/1102wuer.shtml
Dead trees serve many functions in the forest ecosystem and their removal can jeopardize future ecosystem sustainability (see Hutto 2006). Dead trees are a reinvestment in the next forest stand. For instance, one study found that 2/3 of all species depend on dead trees at some point in their life. Most of us are aware of the use of dead trees by woodpeckers, but up to 45% of all bird species use dead trees for roosting, feeding and nesting. Other species from amphibians to mammals depend on dead trees as well. Dead trees are important for invertebrates as well.
For example, ants are among the most important invertebrates in forest ecosystems, responsible for protecting trees from other insects to transporting and planting seeds of some flower species. Plus important pollinators like bees and wasps also utilize dead trees. Another study found that lichens were more abundant on dead trees and some species were solely dependent on dead trees for their habitat. And when dead trees fall into streams, they provide much of the habitat for aquatic ecosystems. Indeed, the studies to date do not show any upper limits on the value of dead trees in aquatic ecosystem. In short, the more dead trees, the better for fish and other aquatic life. There are even new studies that show that beetle outbreaks create higher biodiversity (Muller et el. 2008) and beetles may be a “keystone” species in some forest ecosystems.
FOREST ECOSYSTEMS NEED LARGE BLAZES
Even if thinning were able to slow or prevent fires, such a policy would not be desirable. The vast majority of fires burn a very small acreage—most ignitions burn less than ten acres. The bulk of all acreage charred by fires is the result of a handful of blazes annually. If indeed one believes that fires are ecologically important to forest ecosystems, than we have to learn to tolerate large blazes since they are the only fires that do significant ecological work. For more on the ecological need for large blazes see my chapter in Wildfire Logging and Wildfires—Ecological Differences and the need to Preserve Large Blazes (http://books.google.com/books?id=tnW7iYyp2wYC&pg=PA178&lpg=PA178&dq=wuerthner+on+wildfire&source=bl&ots=oB)
It’s important to note that fires do not consume all biomass. Most fires leave a significant amount of dead wood on the site. This wood acts as a carbon storage mechanism. Indeed, charcoal resulting from wildfires stores carbon for thousands of years, and considerably more carbon than is released by combustion. One could argue we need more wildfires, not less, to store carbon in the soil.
LOGGING NOT BENIGN
When we are considering any management schemes, we must always weigh the presumed benefits against the costs. There is no evidence that logging “improves” the forest ecosystem except by using very narrow definitions of “improvement”. In the long term, logging always is a negative impact if all costs are considered. Thus we should attempt to minimize logging impacts to as small an area as possible.
What is seldom articulated by advocates of fuel treatments and other active management are the real ecological and economic costs of such management. For instance, most fuel management (thinning) involves use of logging roads which are notorious for causing sedimentation, and causing disturbance to wildlife. Logging roads by cutting across slopes interrupt water drainage and hydrology of a watershed. Logging equipment and roads spreads weeds and compact soils (Gelbard and Belnap 2003). (Entire books have been written about the impacts of roads, but for short overviews see Foreman and Alexander 1998 and Trumbulak and Frissell 2000)
Removal of dead and/or live trees can affect forest biomass, which in turn may affect things like watershed integrity and aquatic ecosystems. Disturbance of soils can increase the release of carbon. Logging fragments wildlife habitat. And we should not forget the carbon used in transporting trees to biomass converters or sawmills is yet another release of carbon.
In addition, foresters have no idea which trees will be best suited genetically for survival under changing climatic conditions. It’s possible that the very trees that foresters will choose to remove are those that are best able to cope with ecosystem and climatic variability. Letting nature “choose” which trees live or die is the only way to ensure the long term health and resiliency of the forest ecosystem.
Despite self interested assurances from the timber industry, logging is not an ecological analogue for wildfire (See G. Wuerthner 2004 Logging and Wildfire Ecological Differences) and substantially alters forest ecosystem function and ecological processes.
REDUCING HOUSING FLAMMABILITY FAR MORE COST EFFECTIVE
Restricting construction of homes in fire prone areas is a key way to address human safety and fire-fighting costs. But for those homes already in fire prone landscapes, by far the most cost-effective way to reduce losses to wildfire is by reducing the flammability of homes. Removal of flammable materials for 100-200 feet from homes is all that is required to vastly improve the chances that any structure will survive a major wildfire. Jack Cohen at the Missoula fire lab has written a lot about this topic (Cohen 2000). But mandatory metal roofs and a few other modifications to homes can go a long ways towards reducing vulnerability to wildfires at far less cost than attempting to protect communities by widespread logging/thinning fuel treatments.
FINAL THOUGHTS AND SOLUTIONS
There are a number of major points worth reiterating here. First, beetle and wildfire events are desirable and important ecological processes that sustain, not destroy, forest ecosystems. As a society, we should be striving to find ways to maintain these important processes. Rather than viewing such events as a “negative” , we need to find ways to “live” with such natural and ecologically important processes.
Second, the scientific evidence that actually shows fuel treatments can prevent large insect and wildfires is inconclusive. It appears that under severe climatic/weather conditions, these natural processes (beetles and wildfire) are not significantly influenced by treatments. Plus even under less than severe conditions, fuel treatment effectiveness declines rapidly and may even increase fire hazard. In any event, since the large wildfires and insect events are the only ones that we are concerned about, this raises important questions about the wisdom of applying fuel treatments across the landscape.
Third, forest management is not benign. We should limit forest manipulation to as small an area as possible.
Fourth, the majority of fire hazard is located on private lands (see Schoennagel, T. 2009) for a review on this. Any fuel treatments should be focused on the private lands where it will do the greatest good. Furthermore, by focusing strategic attention to these lands where existing roads create easy access for treatment as well as follow up maintenance, the cost-benefits are maximized.
Fifth, keeping people from building homes in vulnerable locations is another key factor. Just as we discourage people from building homes in the flood plain of a river, we ought to discourage people from constructing homes in the “fire plain”. We are not hapless victims.
POB 719, Richmond, VT 05477
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Wednesday, June 10, 2009
The impact of factory farming upon the American land and native biodiversity is seldom discussed, but animal protein production has a significant impact upon the Nation’s land and water. The direct environmental problems like air or water pollution associated with large factory farming operations may be clear, but less obvious are the environmental impacts associated with the agricultural production of feed crops and other consequences associated with large factory farming operations.
According to the Animal Feed Manufactors’ Association, one third of the world’s grains are fed directly to animals. In developed countries the percentage of grains fed directly to livestock rises to 60%, with 80% of the grains in the United States fed to livestock.
Since the United States is the leading producer of beef cattle in the world, it is also the top animal feed producer in the world, with more than double the acreage in animal feed production than its closest rival China . This means the majority of cropland in the United States is not growing food for direct human consumption as many presume, but is used to grow forage crops for domestic livestock, including chickens, hogs, and cattle. In fact, in the United States, domestic livestock consume 5 times as much grain as the entire American population.
It takes a huge amount of grain crops to support livestock production. For instance, to produce 1 kg of beef requires 7 kg of feed grain. Though chickens are more efficient at converting grain to meat, the ratio is still two to one with 2 kg of grain required to produce 1 kg of meat.
According to Cornell University’s David Pimentel, if the cropland currently used to grow grain fed to livestock were directed towards growing crops for human consumption, we could feed 800 million additional people or more likely provide a descent meal for those whose diet is inadequate.
In order to feed concentrated, confined animals, huge acreages of America’ s best farmland have been converted into monocultures of often genetically modified crops that stretch for miles. The major feed crops are corn, soybeans, and hay/alfalfa with smaller amounts of other grains like oats, barley and even wheat.
For instance, 22% of all wheat grown in the US ultimately ends up as animal feed, rather than in food products like bread or cereal consumed directly by humans.
While it’s difficult to determine how much of any crop is used to feed confined animal operations as opposed to diverse small farming operations, the total impact of animal agriculture of any kind is significant. Consider these statistics.
Globally, production of livestock feed uses a third of the Earth’s arable land In the United States farmland production is even more skewed towards animal feed. In 2008 American farmers, primarily in the Mid-west, planted 87 million acres to feeder corn.
Part of that acreage figure was due to demand for corn created by ethanol, but the bulk of the corn acreage is used for animal feed. By comparison, farmers only planted an average of 234,000 acres across the entire country to fresh market sweet corn, the plant we consume directly for corn on the cob, and other food.
To give some comparison, Montana , the fourth largest state in the Nation is 93 million acres in size. So imagine nothing but corn stretching east and west across Montana’s 550 miles and north and south by 300 miles. This is a huge area to be plowed up, and planted to an exotic grass crop that requires huge inputs of pesticides and fertilizer to sustain.
Similarly the acreage devoted to soybeans is huge. According to the USDA, some 74.5 million acres was planted to soybeans in 2008. And despite the popularity of tofu and other soy based food products, less than 2% of the soybean crop is used for production of food for direct human consumption—with most of the annual soybean crop going for animal feed.
Hay and/or alfalfa are yet another significant crop for confined livestock production, primarily dairy cows and beef cattle. In the United States, approximately 59 million acres are planted to hay/alfalfa annually.To put this in perspective, Oregon is 60 million acres in size.
Though slightly better than a row crop like corn or soybeans as wildlife habitat, hay/alfalfa fields still represent a net loss in native biodiversity and wildlife habitat. Hay/alfalfa replace native vegetation, and often require excessive amounts of fertilizers, and are cut frequently destroying even their temporal value as hiding and nesting cover for many wildlife species.
Taken together these three animal feed crops cover a minimum area over 200 million plus acres. To put these figures of animal feed cropland into perspective, the amount of land used to grow the top ten fresh vegetables in the US ( asparagus, broccoli, carrots, cauliflower, celery, head lettuce, honeydew melons onions, sweet corn, and tomatoes) occupies about a million acres.
If you fly over or drive across Iowa, Illinois, Ohio, Missouri, and other Mid-western states, you’ll pass mile after mile of corn and/or soybean fields. Growing these crops has led to the near-extirpation of native plant communities like the tall grass prairie . Less than 4% of the native tall grass prairie remains and in some states like Iowa which has less than 0.1% of its original tall grass prairie left, tall grass prairie is functionally extinct.
Plus “clean” farming eliminates what little natural vegetation used to remain as woodlots, fenceline strips, wetlands, and other natural areas that in the past supported native species with the agricultural matrix.
Destruction of native plant communities has had serious impacts on native biodiversity. Agriculture, including livestock production as well as crop production combined, is the number source for species endangerment in the country , and this number would be higher if you were to add in the species that are negatively impacted by exotic species, many of which increase due to habitat modification by agricultural production.
Agriculture is also the largest user of US water resources, with confined animal operations the largest per capita consumer of water.
Grain fed beef production uses 100,000 gallons of water to produce every kg of food. By comparison, a similar kg of water-hungry rice uses only 2000 gallons of water, while potatoes require a mere 500 gallons. The primary mission of most western reservoirs is water storage for irrigated agriculture. Even in California which grows the bulk of the Nation’s vegetables and fruits, the largest consumers of irrigation water in the state by acreage is irrigated hay/alfalfa production.
Thus the environmental impacts associated with these dams and reservoirs such as barriers to salmon migration salmon, changes in water flows and flooding, are one indirect cost of factory farming operations. Add to this the direct dewatering of rivers for hay and other forage crop production is the loss of ground water supplies by pumping, particularly of the Ogalla aquifer. It’s easy to see why some argue that livestock production is the leading causes of water degradation.
Agriculture also degrades water in other more direct ways. Livestock produce 130 times the waste of the entire human population of the United States, and unlike the human waste which tend to be treated in sewage plants; most animal waste winds up on the land or in the water. Not surprisingly, livestock production is the leading cause of non-point surface water pollution accounting for 72% of the pollution in rives and 56% of the pollution in lakes.
Agriculture production is also the number one source for groundwater contamination in the Nation, with 49 states reporting high nitrates and 43 states reporting pesticide production attributed to agricultural practices.
Agricultural production is the largest source for soil erosion in the United States with current rates exceeding soil production rates by 17 times with 90% of US croplands losing soils above sustainable rates.
Since the majority of the nation’s cropland is growing animal feed, the majority of soil erosion is a direct consequence of this production.
Another indirect consequence of factory farming is the energy used to grow and transport feed. Animal protein production uses eight times the fossil fuel energy as growing vegetables or grass fed livestock Beef production was particularly energy costly, requiring 54 times the fossil fuel equivalent of non-grain fed sources of protein.
Lest we forget, livestock are a significant contributor to global warming. The world’s livestock produces 25% of the global greenhouse gases, with the waste lagoons of factory farms contributing another 5%.
And according to a UN report, the global livestock sector generates more greenhouse gas emissions measured in CO2 equivalent – 18 percent – than transport.
Much, though not all, of these environmental impacts would be reduced or avoided altogether if factory farming and other kinds of confined animal production were eliminated. A shift to smaller, diverse farms, and a reduction, if not outright elimination of meat consumption, would both contribute to a huge reduction in environmental impacts of animal agriculture.
See Wuerthner, Guzzling the West’s Water in Wuerthner, George and Mollie Matteson, ed. Welfare Ranching—The Environmental Impacts of Public Lands Grazing. http://www.publiclandsranching.org/htmlres/wr_guzzling_water.htm
The Douglas administration has proposed a rule change that would permit all-terrain vehicles to travel on state lands — parks, forests, and wildlife management areas. Presently these lands are closed to ATVs, as are federal lands in Vermont, such as the Green Mountain National Forest.
Ironically this proposal to open state lands to expanded ATV abuse comes at a time when most other states and the federal government are either banning ATVs outright, or attempting to greatly restrict their use. Why would Vermont go in the opposite direction?
If the administration had talked to more of the public or done its homework, it would have discovered that many states and federal agencies are trying desperately to restrict the growing off-road vehicles threat. For instance, New Jersey banned off-road riding by ATVs on all state park, forest and wildlife lands. Why? Because of a growing awareness that ATVs create unacceptable resource damage, increase conflicts with other public lands users, and that restriction on use is impossible to enforce. Currently in New York state there is legislation proposing to ban ATVs on the Forest Preserve and other state lands for the same reasons.
Just a few years ago, the White Mountain National Forest in New Hampshire came out against opening up these federal lands to ATV use. The National Forest managers concluded that ATVs caused unacceptable damage to other resources, and that the agency did not have the funds or manpower to mitigate damage or enforce route restrictions. Rather than allow a use that would be impossible to regulate, the agency rightly concluded not to open forest lands to ATV use. But the problem isn't just local. The former chief of the Forest Service, Dale Bosworth, called ORVs/ATVs one of four major threats to Forest Service lands nationally and urged all national forests to update travel management plans so as to reduce/manage or prohibit ATV use.
It's not just federal agencies that are alarmed by the growing ATV threat. A survey of state wildlife agencies by the Isaak Walton League found no agency personnel disagreed with the statement "that ORVs negatively impact hunting and habitat in your state." And 83 percent said that ORVs did resource damage to wildlife habitat.
A committee of the state legislature of New Mexico released a review of ATV use this winter and concluded, among other things, that "off-road vehicle recreation on public lands increases user conflicts between motorized recreationists and other recreationists and public land users, including ranchers, hunters and anglers." And that these "conflicts tend to be one-sided, with motorized recreationists being less adversely affected and other public land users more adversely affected."
Contrary to assertions by ATV proponents that their use of public lands "benefits" the economy, the New Mexico study found that "ORV recreation incurs substantially higher costs per participant due to natural resource damage, trail maintenance, enforcement, and accident and injuries. The cost of displacement of non-motorized recreationists (including tourists) due to conflicts with ORV recreationists … could be significant in terms of the loss of economic and associated benefits."
In other words, ATVs drive away other users of the land, and this, combined with the higher costs of enforcement, fixing resource damage, and accidents/injuries, means that expanding ORV use of public lands has a net negative economic impact.
There is an outlaw mentality that pervades ATV users' behavior, and it's not just a few riders, as proponents suggest. The New Mexico report noted that "studies show that roughly half of ATV and motorcycle riders prefer to ride off of designated routes" and that enforcement was nearly impossible. Indeed, one study in Colorado found that the majority of ORV riders regularly flaunted authorities by riding off of designated routes. Another Utah study found that of the ATV riders surveyed, 49.4 percent prefer to ride off established trails, while 39 percent did so in their last outing.
In 2004, state lands director Mike Fraysier wrote to a governor's study committee on ATVs, "As you know, state lands in every district are seeing increased illegal ATV use. With this use comes extensive damage and impacts." Fraysier went on to write: "How can the agency, in good conscience, open up its lands to ATVs in light of such abuse?"
How indeed? Some behaviors are just not acceptable in public places. We don't allow smoking in public airports, schools, or restaurants. And we don't allow boom boxes in our libraries. Most of us would never allow ATVs to tear up our yards and lawns. Why should we permit ATVs to destroy our public spaces? Vermont should just say no to ATVs. Keep the riders and their impacts on private lands, but let's protect our public lands for appropriate and compatible uses.
George Wuerthner of Richmond is the editor of "Thrillcraft: The Environmental Consequences of Motorized Recreation," published by Chelsea Green Publishing.