MAN, FIRE, AND THE FUTURE
We have so far written mainly of a single tree species and its interrelation with the other plants and animals within its natural range. A similar treatise for each of the other organisms would also prove of considerable interest and scientific value.
The sequoias included in park reservations were set aside as individuals rather than as communities or ecosystems, most people valuing their uncommon size and age more than their fascinating ecological complexity. Only such rare observers as John Muir valued them as members of a community. Ecology was still in its infancy, its principles hardly formalized by biologists, let alone understandable by the public which viewed them mainly as forest museum pieces.
The attitude of administering agencies was not very different: sequoias were managed as museum pieces, and emotional opportunism more than scientific interest led to their reservation. Stemming from the belief that Mother Nature always knew best, a hands-off policy evolved to attain preservation of the individual trees. It was probably the most logical program that could have come out of the beginnings of park management. Protect the trees from fire and human vandalism and nature would do the rest! But, as we know now, man's objectives and nature's successional plans do not necessarily coincide. The changes took place slowly and either went by unnoticed or were not interpreted as serious until relatively recent times.
Today, in retrospect, we are in an excellent position to comprehend what has happened and why, as is the case with many other ecosystems as well. In the first place, the Act which created the National Park Service in 1916 by no means explicitly directed how man should accomplish its stated goals. Secondly, the magnitude of forest destruction by fire led to such abhorrence of it that its role as a natural environmental factor was all but overlooked.
The phraseology of the Act's first stated goal created a semantic problem. Park management was to guarantee "the maintenance of the scenery and the natural and historical objects in such a manner and by such means as would leave them unimpaired for the enjoyment of future generations." The impreciseness of "unimpaired" reflected the general lack of knowledge regarding biotic communities. Certainly, the word was well intentioned, as were the equally elusive terms "preservation" and "maintenance in a natural condition," both commonly used. On the other hand, interpretations by park administrative personnel varied, and therein lay the trouble.
The vagueness surrounding this terminology permits at least four possible interpretations of the goals for sequoia management in national parks.
In the earlier years of National Park Service sequoia management there was no definitely stated goal for the species, although the second possibility above was the one seemingly sought. Since then, park administrative personnel have gradually discarded the rather indefinite ideal of preservation of individuals and have accepted in lieu of it the goal of maintaining sequoias' ecosystems on a continuing basis. The transition was not by unanimous consent, and caused occasional sharp differences, especially when persons advanced new ideas based on scientific understanding of the species. In particular, the use of fire as a management tool created understandable differences.
By the time of inception of the National Park Service, the American mind saw fire as something to prevent or to extinguish at the earliest possible opportunity. Little or no compromise was allowed to this philosophy which the forestry profession drilled almost unrelentingly into the public mind in order to remind people to be careful with fire. The earlier literature seldom mentioned fire as a management tool, even though primitive peoples in most parts of the world had so employed it in a rather unsophisticated manner (Reynolds 1959; Stewart 1956). The earlier stages of succession often produced plants valuable for food which were scarce or absent in the later stages.
In the Sierra, early cattlemen would "fire" the hills as they brought their herds in late autumn to lower elevation winter ranges. Where shrubs and trees had once dominated the landscape, more palatable forage crops now grew in their stead. Their fires, however, could scarcely be called "prescribed" and, on occasion, were rather devastating to values important to others. Even John Muir, who appreciated the role of fire in sequoia reproduction, bitterly criticized such burning. With serious concern developing over forest destruction, safety with fire became an almost universal byword. The term "prescription" in conjunction with the use of fire was probably not yet coined, despite burning practiced in the South to aid the growth of long-leaf pine. Almost always, the forestry profession wrote the end products of fire on the debit side of the ledger.
The use of fire as a management tool began to captivate more and more people, some of whom attempted to make public its practicality for certain specific goals. But such visionary persons were to remain a minority for many years, with voices often stilled or subverted by editorial prerogative, public apathy, or utter disbelief. Only recently has this philosophy come into the fruition many would have wanted decades earlier. Even so, it still escapes much of the general public, and even some foresters and biologists are far from agreement upon the subject, however soundly based their concepts may be.
The term "prescription" is used to separate that kind of burning from wild fire and to indicate that man chooses the conditions under which to burn, thus seeking to realize his goals without creating undue hazards to other forest values.
Prescription burning has two broad goals: (1) reestablishing certain desired vegetation types of earlier stages, and (2) reducing excessive fire hazards that have accumulated in the absence of fire.
In 1955, Herbert Mason of the University of California pointed out that, in the absence of fires in the Sierra Nevada, valuable sugar pine was being replaced by the much less valuable white fir. Some action was necessary to change this ecological trend, or the forest's economic values would be reduced. Although the die was seemingly cast in favor of fire as a management tool, the public and its governmental agencies were not yet ready for such a reversal of an old policy. Admittedly, too, prescription fires might get out of control. Who wanted to shoulder such a responsibility?
Another possible vegetational change resulting from prescription burning is the improvement of forage crops for both wildlife and range animals. With the advance of plant succession, habitats become less suitable for many desirable forms of animal life and the resulting decline in their numbers is a disadvantage to hunters and nature enthusiasts alike. These changes have obvious social and economic implications.
Certainly, man never intended to create conditions under which the giant sequoia could not reproduce itself, but did so inadvertently. Problems demand solutions, and the best solutions are generally derived from a consideration of alternatives. This is especially important where manipulation by fire may provoke adverse reactions from the uninformed public and prejudiced park and forest administrators. Very often, however, the serious weighing of alternatives has led to the realization that fire is the only economically feasible method to attain certain management goals.
The sequoia fire story presented in this book is a good example: our suggestion that experimental burning could teach much about the ecological relationships of sequoian communities met with expected skepticism and opposition by some park officials and public alike. Why not rake up and haul away the ground litter which was preventing sequoia reseeding and also adding to the fire hazard? Some simple arithmetic provides the answer. Leaf litter which is commonly up to 2 inches thick would, if raked up, fill up the equivalent of four railroad gondola cars for every acre of land so cleared! This would not include the limbs, trunks, and cone accumulations that are such serious fire hazards; it would neither open the crown canopy to the penetration of light nor effect the conditioning of the soil referred to earlier. Clearly, this alternative to fire is out of the question.
The accumulation of combustible debris in the absence of periodic fires has, in many areas of sequoia groves, created fire hazards that are perhaps higher now than at any previous time in human history. Biswell (1961) and Hartesveldt (1964) report that fires that prevent such fuel accumulations recurred regularly before man's intervention. In intensive studies in the University of California's Whitaker Forest, Biswell produced convincing evidence that fuel conditions not only were extremely critical but also impaired the sequoia's aesthetic values for the park and forest visitors. Manipulations under his direction showed what could be done to alleviate the situation and solve both problems at the same time. The cost of manipulation is high in the case of dense fuel accumulations.
In some sequoia groves, the fuel build-ups are too great to use prescription burning without considerable preparation. Hand removal of the larger materials is beyond consideration, and the longer no action is taken, the more difficult the solution becomes. Once reduced, fuel can be consumed rather easily by repeated burnings of the pine straw and other ground litter. In this manner, fire hazard could possibly be kept at a minimal level on a continuing basis.
The trend toward fuel reduction by fire has begun through official sanction in Yosemite National Park and in Sequoia and Kings Canyon National Parks, where irreparable damage could result to sequoia groves if raging fires were to enter from outside the boundaries. To date, more than 150 acres of sequoia land have been burned in Kings Canyon National Park and much valuable information is being gleaned from the results. We admit that fire is no panacea for all forest problems, and each situation demands judgment on its merits before any one silvicultural solution is chosen. But the trend has begun, and greater understanding of fire's natural role should continue to favor its use as a tool in the management of various ecosystems.
Although tending toward a hands-off philosophy of management, the older park policy could not be totally regarded in this light. After all, extinguishing wildfires that started by natural means is a form of interference by man. But aside from this one notable exception, vegetation management within the parks was largely one of letting nature take her course. Wider recognition of the undesirable changes being induced in natural ecosystems gradually led to the more intensive management of park ecosystems, a change in philosophy that was slow and hardly universal, and a bitter pill for some traditionalists. For them, noninterference management, other than fire control, was akin to the gospel. Amid heated differences of opinion, a Yosemite National Park superintendent in 1934 countered the traditional with the shocking thought that ". . . our flora and fauna have not been primeval for decades."1 Next, in the text of a talk prepared for the California Academy of Sciences, he stated forthrightly that
". . . the only way the nation can salvage even an aspect of the primeval is through a scientific and prayerful management." While not a scientist, he was somewhat ahead of his time, but his sage advice was diluted in a rather lengthy exchange of ideas about the law's intent regarding park management goals (Hartesveldt 1962).
Considering the debate within the National Park Service, we might expect bewilderment in the general public. However, the lack of direct communication has all but precluded their full comprehension of the argument throughout the many years. Only with the announcement that fire was to be used experimentally did a much larger segment of the public become aware of the vaunted sequoia's complex ecosystem. Here was a new and fascinating concept. Ecology was becoming a household word and people were now beginning to see the forest for the treesall of the trees, and their associated plants and animals. Any fears that the public would reject the management of sequoia parklands, including the use of fire as a management tool, were apparently not well founded. Where logical scientific explanations were offered, the public was seemingly willing to accept drastic changes if they believed it would safeguard their sequoia trees. Many gained much morean educational revelation, a new way of seeing nature, with principles broadly applicable to other ecosystems as well.
We are gratified that we are able to close by refuting a rather dismal prediction: the giant sequoia's slow but certain demise in the face of a warming climate and the indelicacies of mankind. After 135 million years of developmental history, this tree is not about to make its final exit. Climatic change is slow, and we cannot predict what changes will occur, if any. Mankind did exact a toll from the tree; yet it has responded as if to flaunt man's influence and it is reproducing and growing vigorously where man has apparently damaged both the tree and its environment. Man has assumed the role of benefactor of nature, a role in which he can well expect to perform better than he ever did in the past. We now have the knowledge which, when implemented, will help maintain sequoia communities on a continuous basis, and there is every indication that these magnificent trees will grace the western slope of the Sierra Nevada indefinitely.
And so ends our story of the giant sequoias, the greatest of all living things upon this Earth, a story the tree began in the misty Mesozoic age of reptiles. But, is it really the end of the story? We think not. We are merely closing our version of it as we see it at this point in time. And we further suspect that as long as man wonders over the unknown, and as long as there are sequoias reaching for the Sierran skies, curiosity will forever provoke man to probe into that which others have not yet known or have misunderstood. We fully expect, then, that the sequoia story will never be told in all finality, and that its mysteries will provide a continuing fascination for mankind.
Last Updated: 06-Mar-2007