For the Love of Fire
by Allan Savory
As we witness the American resource management pendulum once again swing back to promoting fire as the major management tool to reduce fire risk and brush encroachment and maintain grasslands and savannas, one wonders what prompts such love of fire when all evidence points to its destructive capacity. To understand why this occurs we must go back in time.
Humans’ Relationship with Fire
Imagine sitting in a cave 500,000 years ago. We are improving our lives by learning to use tools. We are able to dig roots more easily with a sharp stick. We are able to kill sickly animals by throwing stones. And we have found we can kill an adult calving deer by hammering her to death with a stone in our hands. We have also learned to carry fire and use it to cook and to burn animals out of grass cover. Thus, we observe we have two "tools" with which we can influence our environment – "fire" and "technology," although the latter – our stones and sharp sticks—are very primitive by today’s standards.
Next we visit the cave some ten thousand years ago. We are amazed that the people have become so advanced. They are larger and better fed because they have learned to speak and organize themselves when hunting in packs. They have become a predator and are no longer merely omnivorous scavengers only capable of killing almost immobile young animals. While they still find it hard to isolate animals from herds as other predators do, they have overcome that problem by the use of fire and their ability to communicate complex messages. In this way, they feed royally on hundreds of animals driven into bogs and rivers, over cliffs or surrounded by fire and burning. Their tool of ‘technology’ has developed to very skillfully made stone spear and arrow points, and they are capable of spearing mammoths, the largest of animals. But, they have developed no new tools to manage their environment.
Finally, we pay the cave a visit today and admire the paintings later people did on its walls. People no longer live in it. Today, our tool of ‘technology’ is amazingly sophisticated. We drove to the cave in our Lexus, using the most modern GPS navigation while chatting to friends on our cell phone. On the way over we ate at a restaurant that used electricity to cook our food.
If we are observant and thoughtful we notice that in the intervening 500,000 years that while our technology became more sophisticated, we did not add any new tools to our toolbar with which to manage our environment. Along the way we did domesticate many plants and animals, and even learn to use small animals and insects as tools to manipulate the immediate environment around their crops, but no new tool emerged to help us manage the environment.
We also learned along the way that when we killed out the original animals with fire-induced changes and increasing hunting skill and replaced them with our domestic livestock the land deteriorated in many cases to unproductive desert where it had been savannas supporting many millions of animals. This observation led us to add a new tool to our arsenal for environmental management – the resting of land or the tool of "rest". Our first new tool in some 500,000 years. So now we have three tools for managing the environment—technology, fire, and rest.
Throughout this vast time, many brilliant humans used these limited tools in thousands of different ways. But we note that no matter how hard they tried not to do so, they turned vast areas of once productive land into deserts. Today in America, despite more range scientists than all countries combined probably, eroding soil outweighs all other exports combined as land degradation marches on unchecked regardless of status as private or public land, wilderness, or national park in our low and seasonal rainfall environments.
We all want this degradation to reverse. We want to see the lands regenerating again. That’s why resource managers often use fire. Humans have used that tool for so long to meet their needs (hunting, cooking, heating, etc.), that we have come to believe it is tool we can use to solve this current crisis. Let me explain why that isn’t the case.
Nature Functions in Wholes
It helps to understand what is happening to the life cycle of plant material in grasslands and savannas because these areas constitute the bulk of the earth’s land area. There are four broad types of plants – trees, shrubs, forbs (some call them weeds) and grasses. Trees, shrubs and forbs are generally evergreen or deciduous. Evergreen plants keep most of their leaves year after year while deciduous plants grow new leaves in spring and summer and shed them in the fall. If deciduous plants could not shed their own leaves, the leaves would not decay and would keep the light from young buds which would kill the plant in a two or three years. Thus we observe that deciduous plants maintain the life cycle—birth, growth, death and decay—by cutting off their own leaves to ensure the continuance of the life cycle.
Grasses, which dominate vast areas of the world’s seasonal rainfall environments, also have leaves and stems that green up and grow through the growing season. They, like the deciduous plants, also withdraw food from the leaves and stems which change color as the dormant season approaches. However, unlike deciduous plants, grasses withdraw food from dead stems as well as leaves. And unlike deciduous plants no grass in the world can shed its own dead leaves and stems so that they can decay on the ground.
The grasses of the world never developed the ability to cut off and shed their own stems and leaves for the simple reason that they did not need to do so. In a world that only functions in wholes, and in which soils, animals and plants coevolved, the large herbivores that we still find remnants of in grasslands and savannas performed this task. The large herbivores did this in return for being fed and kept alive. Had the grasses shed their own leaves and stems to decay on the ground, the animals would have died.
The functioning of nature’s wholes is even more fascinating. The billions of micro-organisms alive at the soil surface that were part of the plant material breakdown process were themselves largely killed off in the long dry periods characteristic of seasonal rainfall environments. And the large herbivores were unable to digest the fibrous matter in the grass plants so again we see a partnering. The large herbivores had moist gut environments in which micro-organisms flourished. In return for this safe haven, they assisted their hosts in digesting, thus ensuring the biological breakdown, of trillions of tons of plant material every single year to sustain biodiversity and life cycles. On the other hand, fire, in all instances, speeds the chemical oxidation process and decreases biodiversity.
Rest Isn’t the Answer
As one can observe over most American rangelands, without enough animals to remove most grass leaf and thus maintain biological decay, the old material oxidizes and gradually weathers and breaks down physically just as would deciduous plants if they could not remove their own leaves, strangling the plant. Tragically, and starting thousands of years ago, we attributed the death of grasslands to overgrazing despite the few domestic animals that replaced former vast herds running to many millions. That humans made this mistake is understandable if one looks at areas where animals lingered and genuinely did overgraze plants. But as we have known for over fifty years now, overgrazing of plants has nothing to do with animal numbers. It is purely a matter of the number of days the plants are exposed to the animals and how soon they are re-exposed. This simply is why vast hordes of millions of grazing animals on the move did not damage plants as our pitiful few livestock do today.
The fact that the pendulum swings as predictably as it does from resting land to again burning land to try to keep grasslands alive is perfectly understandable as soon as we recognize the limitations of our only scientifically acceptable tools to manage the world’s environments. Although range scientists in Texas and Arizona in particular have gone to great expense and effort to develop machines to mimic animals, there is no technology that can restore biological decay like a live herbivore managed properly. Nor is there ever likely to be any such development that could be applied to literally hundreds of millions of acres worldwide annually.
The tool of rest as we observe in all government experimental plots established in many Western states leads to biological decay changing to oxidation and biodiversity loss and bare soil in low rainfall. As rainfall increases the plots show more shift to woody plants and bare soil with algae and lichen crusts being the last life left.
This only leaves us with fire in our toolbox. So understandably we use it, and the people doing so justify it in numerous ways—calling it natural or referring to early people’s skills in using fire, or giving it a bureaucratic blessing a ‘prescribed’ and, thus, ‘scientific’. So we alternate over and over between ‘rest’ with its slow oxidation that kills most grasses and biodiversity while producing high percentages of bare soil between plants, and fire, which oxidizes the old material quickly greatly polluting the atmosphere, creating bare soil and losing biodiversity. And then we marvel at the fact that the deserts of the world are advancing at an accelerating pace!
There is one new concept that we only developed an understanding of through studying the many government research plots demonstrating the effects of removing animals from the land and that was ‘partial rest’. Partial rest is the situation that occurs when there are a few elk, deer, bison, sheep, cattle, horses or whatever large animals on the land but not running naturally in vast herds with accompanying pack-hunting predators. In these situations, so typical of rangelands worldwide, the few animals do overgraze and over browse plants where they linger. However, most plants do not have the old material removed, and oxidation sets in, so that in low rainfall environments, bare soil and algal crusts increase. In fact, if one studies the experimental plots where the land inside them is totally rested and deteriorates seriously, the exterior with too few animals wandering is always in about the same condition.
Before we understood the fact that rest was so detrimental in brittle environments and partial rest had essentially the same effect, the interpretation of range and wildlife scientists was that the best nature could do was indicated by the total rested land and thus our management which was about the same result was not too bad! That we should have misunderstood the effects of resting land is also understandable for two reasons. First, resting land is the most powerful tool available to us to restore biodiversity in perennially moist or non-brittle environments and, secondly, we did not have the concept of the brittleness scale of environments until the development of the Holistic Management®Ò decision-making framework.
Grasses, Grazing, and Fire
The general effects of human management of rangelands using fire and technology have been disastrous if we are honest, despite many years of well-meaning effort. As grasslands die out due to overgrazing of some plants, over resting of most plants, and consequent oxidation and shifts to woody and herbaceous plants and bare soil, people tried to arrest the process over centuries.
The shift from dying grassland to woody vegetation has long been observed. What we are now seeing all over western ranges in the U.S. is the simultaneous shift to a limited number of low productivity grasses. The original highly productive grasses were very animal-dependent (very susceptible to early death with the accumulation of ungrazed stem and leaf). As these grasses disappear, we find our ranges dominated by species that are highly rest-tolerant and able to stay alive, although far from healthy, when oxidizing material clogs the plants. Typically these are grasses short in stature (Gramma), fine leafed (Aristida), or having branches like a tree (Tobossa). It is amazing today to see such grasses now dominating millions of acres ranges of totally different soil types and climate from Montana to California to Texas instead of the vast array of species that should be prominent. That the seed of other grasses is still around is illustrated by one of the first ranches I worked with in the U.S. On this we had the three types of grass mentioned at the outset. After three years of using animals to restore decay we had 19 species of perennial grasses.
As people observed dying grasslands shift to woody plants and forbs they did not sit idly by. However, with only one other tool in the tool bag, fire, they used it. Thus, we see the development of various grazing systems and rotations that utilized fire at some point. A well-known example of this was the three-herd, four-paddock system developed by Scott and Tidmarsh in southern Africa. In this system, every fourth year a paddock was rested for the year to provide enough dead grass to enable the managers to use a really hot fire to kill the incoming woody plants. There are many combinations of grazing, resting, and fire as people have over the ages tried every imaginable way to get the two tools of rest and fire to overcome the effects of grazing (which was really the overgrazing of plants and partial rest of the range).
The latest fad catching on in America is Grassbanks which is a well-meaning effort to restore rangelands and thus prevent ranchers leaving the land by providing land (the grass banks) to which participating ranchers can move their animals. This enables ranchers to rest their own land while building up enough material to burn and prevent the movement to woody plants.
No Justification
Unfortunately the use of fire not only increases soil erosion, but as recent research shows, it is extremely polluting. Pollution from grassland, savanna, and forest fires of North America, Africa and Australia (as well as other countries) is contributing considerably more to global climate change than was ever suspected. The gasses put out by these fires (prescribed or not) are far more damaging than just the carbon they add to our atmosphere. It is said that an average range fire of one and a half acres puts out more damaging gases than 3,000 cars do per second. Range fires in the Americas, Africa and Australia are now some of our greatest contributors to global climate change, indicating it is time indeed for range managers to open their minds to other tools such as large herbivores that maintained grasslands for millions of years before modern humans.
While scientists prescribing fire justify its use with myth and anecdotes, in over forty years of studying the matter, I have not been able to locate a single piece of published data that shows that it does not damage our environment. Superficial studies of short-term vegetation changes abound. One would imagine that after a century of scientific studies of fire management there would be some documenting improvement in soil and soil life, water and mineral cycling, enhanced biological decay, and increasing biodiversity. The absence of such studies is of concern.
Tragically with only the tools of technology, fire and rest to manage our wonderful national parks some of the best are being burnt every second and third year to try to maintain grasslands and savannas. At the same time these parks annually cull (shoot) thousands of animals that are essential to keeping such grasslands alive. I am very aware of the problem and the scientific reasoning behind this killing of animals, as it was my own faulty research that began this process of culling large numbers of animals in Africa’s national parks in the false belief that there were too many animals. My training, and thus beliefs, were the same as those of my fellow scientists today advocating endless stock reductions and the resting of land. Because these beliefs and my training were thorough, I, as all humans do, misinterpreted my research to make the results conform to the prevailing beliefs. It is interesting that those scientists at the time brought in to critique my work all concurred with me as they held the same beliefs.
Fire will always remain a tool to be used in certain situations. But if we are serious about addressing the greatest problem facing humanity (biodiversity loss and consequent land and ocean degradation), then we need to drastically reconsider our attitudes about burning and large grazing herbivores. As public concern grows over the loss of this valuable resource, it will soon make it unacceptable for range and wildlife managers to keep swinging between fire and rest, fire and rest, fire and rest while our grasslands turn to desert.
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