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Sustained forests; sustained profits
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A fire management system has all of the system components discussed in the Introduction. It is one of the most difficult systems to design because it has both positive and negative elements and these are both (in part) very conspicuous and people have strongly held beliefs and deep-seated, perhaps innate, fear of them.
No other aspect of land management has caused more controversy, has taken precedence over more management activities, has involved more resources on the private, state, and federal levels, and has been more unpredictable than fire management. It involves every aspect of land management, thus of its plans. The very nature of fire behavior is responsible for these phenomena. As natural resources are continually utilized in a quest to provide for the needs and wants of people, the value of all factors of production, i.e., land, labor, and capital increases at unprecedented rates. Thus it is becoming increasingly important to identify the benefits and costs associated with decision making so that these resources are used in the most efficient and productive manner. For this reason, a fire management system is needed so that no more resources than necessary are used, that associated risks are identified and minimized, and prescribed fire is used effectively.
The many components of fire management, and their interrelationships, may form a complex system. Rothermel (1980) observed that a remarkable number of programs or systems were introduced in the past 10 years and listed subsystem topics of logging slash, flammable shrubs (season and age), fuel moisture, windspeed, fire spread and intensity, flame length, scorch height, burning time, spotting distance, fire containment requirements, and fire shape. Integrating all of these with comprehensive plans for resource areas is one of the greatest challenges of modern planning and is still beyond The Trevey capability. A proposal to advance such work is available. Nevertheless, a beginning has been made.
Lotan (1977) noted the relations of fire management to planning are extremely complex and observed that Jack Borrows had formerly advocated a "systems approach" to fire management.
Chase (1987) lamented lack of public understanding of fire management and the need for clear expectations from a fire management program. It is so complex, that such understanding is unlikely except for a very few. The difficulty will be in replacing "number of fires", "acres burned", "deaths", "costs", and "days fought" with a more meaningful system performance measure. The need is to change R, the expression of how well the objectives of the larger system are being achieved. Requiring an economic efficiency criterion (begun in 1980) such as minimizing the sum of present discounted fire management system costs, plus the net charge in present discounted resource value estimates due to fire (Flatman and Storey 1979; Chase 1987:62) has not simplified the problem. This is a loss/cost reduction criterion and does not address the potential positive effects of skillfully used fire. Althaus and Mills (1982) however did include willingness-to-pay criteria as estimates of benefits that may result from fire management.
More and more homes are being built at the forest/urban interface. There is inadequate adherence to safety rules. Current regulatory codes are inflexible. Specifications for building and site characteristics cannot be adjusted to accomodate homeowner values. An "ignition assessment" may be an alternative to current safety codes.
The problem areas:
Bratten et al. (1981) observed that fire control is very expensive (now over $300 million per year) and that a comprehensive total fire management system can potentially save enormous amounts of money. The system needs to include innovative, area-specific efforts.
The components of the fire system include:
Trying to discover the types of people who set fires or engage in high-risk behavior has been found to be useless. The costs are so great that an adequate sample size cannot be gotten due to variations in individual behavior, use, fuel, area, vegetation type, even season and year (Folkman 1977).
Fires are never simple. Their size, intensity, and effects relate to:
Some say plant adaptations have been made to fire intensity, frequency, and season.
Chase (1987) warned against optimism in new technology for fire suppression. He perceived increases in human population, their age structure, leisure time, and mortality and therefore increases in fire management needs. He was pessimistic about technology, its application, and the chances for reducing costs of equipment (e.g., air tankers). He advocated (as we do herein) improved analyses of methods and costs and sharing of resources and action among agencies. He made a strong case for an integrated planning approach such as attempted within The Trevey.
Anno and Brown (1989) suggested different strategies in wilderness, general forests, and the residential forest. We move past the custodial and strict fire control strategies of 20 years ago and seek, with fire scientists and others, management that includes cost-effectiveness as a criterion, using fire to "clean-up" and to achieve desired conditions, and allowing fire to operate as a natural factor in certain ecosystems. We move past seeing fire as a process, or as a tool, but as an entire general system potentially laid over the land unit to be managed. Fire management means integrating efforts of many disciplines to assure that fire does not prevent land managers from achieving their objectives and to assure it participates cost effectively in achieving certain objectives.
Performance Criteria
An answer to "How does anyone know how and when they have a good system?" is the essence of the meaning of performance criteria. Performance criteria are expressed by indices. They will be an indication of how well any system meets the stated objectives for it. Some of these criteria for the system are:
Context
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| Early detection and rapid attacks were part of former fire fighting strategies. Many such towers were located throughout the country. |
Problems throughout The Trevey are said to exist in the gap between the present condition and the desired condition. The latter is difficult to define and decide for a fire-related subsystem. Expressing that desired condition is a first task because it is perceived to be very difficult. Even then, the first efforts are expected (and encouraged) to be revised. After the objectives, an overview is presented with concepts and guidelines that are to be used in the fire management system for the Station in the near future. The emphasis herein is on fires typically non-structural in origin.
Objectives
Type 1 objectives are:
In natural systems (parklands and areas served for their wilderness character) fires can be a factor in stimulating plant growth, retarding growth of other plants, and eliminating some species. Some plant species have disappeared from fire-protected areas. Fires obviously change moisture, chemical, physical and other factors having long-term effects on plants and animals. They consume organic matter, kill trees, and expose soil to rainfall.
Plants of many types have structured growth and reproductive modes, presumably in response to fire as a selective force in the environment. Some plants require fire for seed dispersal and germination, for seedling establishment; others require long fire-free periods to establish seedlings and fire-resistant barks or growth. Some seeds need fire to germinate. Some have rooting patterns that appear fire related. They rejuvenate the community but also provide rapidly a canopy. Some depend on fire-resistant species for shade in their early stage. Some (e.g., grasses) are abundant after a light fire, others are removed or seeds destroyed. Whether fire is "good" or not, or whether the post-fire condition is "good" is very much a human perception, and it varies. Biodiversity, discussed in the Variety chapter, a much-discussed objective, can be increased or decreased by fire.
A fire of a certain character may be prescribed. Skillful fire managers can cause such fires and associated conditions to occur. Fires offer, in many situations, a low cost-per-unit-area means to obtain desired vegetation and communities. Fires, do however, cause air pollution; may allow soil erosion; and cause losses of available nitrogen to plants. Fire cannot be allowed to destroy human structures, intensive land use (crops and tree farms), or human lives. The conflicts are evident, often profound, and increase as more and more human structures are built at the edge of areas preserved for their natural conditions (one of which may be infrequent fires).
Van Lear (1991) observed that fire suppression has allowed the composition of regional forests to change. Oak species may no longer dominate sites where fires have been suppressed. Species intolerant of fire (e.g., mockernut, hickory, scarlet oak, red maple, and blackgum) may grow, develop thick bark, and resist future fire damage. Laurel and rhododendron may become very dense and prevent trees becoming established after fire. Frequent fires over many years favor oak (Quercus) by reducing competition of the under and mid-story plants and improving conditions for acorn-cashing squirrels (Van Lear 1991). Acorn germination may be enhanced due to fire-caused insect losses. Fire, once common in the natural-events of stands, appears necessary to assure oak regeneration on sites. Suppressing fires results in other species gaining dominance. Oaks have many financial as well as soil, water, and wildlife advantages.
Van Lear (1991:17) observed that moist sites are converted to very dry sites by intense fires or by many low-intensity fires. Only "tenacious ability to resprout" explains the ability of oaks to dominate such dry sites.
In general, fire in eastern hardwoods:
To produce mixed hardwood and pine stands we will:
Periodic burns in mature forests in late winter can increase understory plants (grasses and forbs) richness, but predictions of effects of fire on individual species are impossible. Each response is probably unique. The same species is likely to respond differently in different areas. Managers are likely to get very different responses to some summer, some fall, and conventional late-winter or early-spring burning. Under the controls possible on the station, such burning in small areas on windless days soon after a rain can achieve plant (and related animal) richness.
The unknowns about the effects of fire on regional hardwoods suggest the need for a very conservative approach to its use. Only on better sites can fires be used that are (1) low-intensity, (2) in light fuels, (3) during the dormant season, (4) where spread density is low (no residential danger), and (6) all smoke management criteria can be met (cf Van Lear and Waldrop 1989). Under such conditions, the expected returns per unit effort seem very low and rarely positive.
Waldrop and Lloyd (1991:45) found coastal pines unaffected by burning during 40 years of study. Small hardwoods are killed or re-sprout. Sprouts can be killed by annual or short-period (1 time every 3-4 years) burns. Sprouts are replaced by grasses and forbs.
Small areas of the wetland, when very dry, should be burned to assure natural conditions and resulting biodiversity. Of course tight controls are needed, but the resulting vegetative change and exclusion of invading woody shrubs will enhance the natural variety now being lost due to fire suppression. An alternative, though with slightly different results, is to use fences and intensive grazing of livestock to radically change small areas.
The biomass of herbs in grasses per m2 (B) can be estimated from the percent of herb cover (C)
B=1.81C-0.03 (Gilliam 1991:119)
There is usually about 20,000 kg of forest litter per hectare (17,800 pounds per acre) in the pine forests of the area. Fires reduce this in relation to their intensity. In some cases almost none is removed, in others, all of it. Fire intensity and the amount of litter present determines how much nutrient is made available from a fire.
Forest floor litter of value to plants and animals and erosion control is said to be a hazard and increases the influence of fires. The higher the fuel load, the greater the intensity (Dodge 1972). Thus another of the many conflicts within the fire management system.
Mycorrhizae are some of the soil fungi. Their "root-hair-like" hyphae are structures within soil. They are very important in determining how forest and cropland ecosystems function. They serve as additional "roots", transporting moisture and nutrients among other plants. Without them, many plants fail to develop beyond germination or they grow slowly. They and the relations in the soil, are easily distributed by grazing, recreational impacts, and fire. Dry soils reach higher temperature during fires and suffer the most mycorrhizal loss. Nevertheless, colonization is usually rapid. Effects are likely or most evident on the host plant, not the mycorrhizal colony.
Simard and Donoghue (1987) have found strong mathematical relations between fire occurrence and latitude, between length of fire season and latitude, between fires and non-metropolitan population and arson fires, debris-burners and enforcement effort. Acres burned is a function of escaped fires over the past 20 years. The extreme variation in costs of suppression, prevention, and other actions in fire management has prevented optimal solutions from being realistic. Fire is, after thought, realized to depend more on structures present in an area than on vegetation or land characteristics. Little is known of substitutabilities (e.g., prevention of arson fires vs debris burner fires) (Simard and Donoghue 1987). The plan is to spend limited effort on region-wide public education, then to concentrate on objectives, seeking ways to shift R the most per dollar. Strong use of incentives and rewards (at least announcements such as "no fire for 600 days") will replace much general education.
Wilderness fire management includes letting natural fires burn but also the constraints--only to the extent that we have the capability to continue it when and where we decide (Mutch 1976), and only to the extent that it does not greatly affect an anadromous fishery, air quality, or adjacent non-wilderness land unit (Mutch and Briggs 1976).
The conflicts that exist between the naturalness of fires, the role of fire in natural ecosystems, and the effectiveness and low cost of fire in achieving certain objectives (e.g., land clearing) and the threats and losses due to fire are great. The effectiveness of suppression actions decreases as wilderness fires increase in size, thus the manager's dilemma of managing a forest with natural means but increasing the danger of an "escaped fire". Resolving the conflicts is a profound task, only partially completed. A model, with the GIS computing fire risks and attack priority is needed and planing is underway for its development when funds become available.
Nutrients
In precipitation falling through smoke from forest fire, the concentration of Na, K, Ca, Mg, and N is greater than in normal precipitation. Similar (and greater) contributions from fires are made to areas adjacent to fires in smoke and dry particulate matter (Clayton 1976).
Fires have one of their most significant effects on forests in causing losses of forest floor nitrogen. Two strategies to overcome this loss at low costs (i.e., not using commercial fertilizers or manures) is to retain large woody debris and to re-seed all burned areas rapidly with nitrogen fixing plants.
Estimates of wet deposition of nitrogen to forests are about from 5 to 10 kg per hectare. With dry deposition, the total is from 6 to 14 kg per hectare per year. Maximum fixative rates are probably 6 kg per year in eastern forests, but are more likely to be 1-2 kg per ha per year. Dead wood associations probably contribute about 1 kg per ha per year. These associates are the forest wildlife, the termites, beetles, and roaches, as well as the more conspicuous animals. Total insect biomass is about 3 to 4 kg. In burned stands arthropod densities in the litter one year later are usually reduced significantly, 20-80 percent. The old forests have fewer species (less richness) but more abundance than younger forests. (See the section on "Variety and Biodiversity"). The nitrogen-fixing legumes (of which there are 300 natural species in the Southeastern US) only contribute 1 to 9 kg of nitrogen per ha per year (1-8 pounds per acre) (Boring et al. 1991).
In coastal plain ecosystems, light fires only volatilize about 24 kilograms of nitrogen per ha (20 pounds per acre). Nevertheless, this is usually considered a growth-limiting nutrient, so even small losses may be important. In intense fires in mature stands, several hundred kilograms of nitrogen per ha can be lost. This is about equivalent to the amount brought in by precipitation (after losses to stream runoff).
Difficult to study, and thus poorly known, nitrogen remains one of the most important components of all ecosystems. The nitrogen budget of ecosystems needs further work but in the meantime, managers know what to do. Reduce its loss; augment its collection and fixation by any cost-effective means.
Fire generally increases nutrient availability in relatively nutrient-poor soils. Prime flatwoods are especially limited by phosphorus (P) and potassium (K), levels that are increased by fire. McKee (1991:405) claimed that without burning, calcium (Ca) may be immobilized in the forest floor and may lead in time to a magnesium:calcium imbalance and thereby alter the soil formation processes.
Smoke
Maintaining high air quality is a recognized objective. Minimizing smoke, ash, and odors are desired ends (Clean Air Acts of 1963 (P.L. 88-206) and 1970 (P.L. 91-604)). Maintaining ecological communities requiring fire. . .but not producing smoke, is an awesome demand. Maintaining communities as well as air quality are legal mandates not potentially at odds. In the future, the plan is to seek means to clarify the means (not the intent) of these laws. The management agencies need the rights, along with the mandates, to use fires when conditions are right to cause the desired ends. Trade-offs will be made to minimize soot, ash, smoke, odor, etc., but effective vegetation influence is needed based on soil conditions, fuel moisture, wind, likely future precipitations, and many other factors.
Fire is a natural and renewing force in many ecosystems. Smoke, however, is a natural component of fire. We must minimize fire to minimize smoke but realize smoke has minor other positive dimensions. We must encourage desired fires and their smoke, but at the appropriate time and conditions. Cramer and Graham (1971) demonstrated years ago that smoke-sensitive areas can be mapped, and that public licensing of burning allows burning (e.g., timber slash) when smoke does not exceed the atmospheric capacity, or when it will be dispersed well. They presented conditions under which smoke or its potential effects would be minimal (e.g., elevation, wind direction, precipitation, air stability, and burning techniques).
Specifically, when there is a negative answer to any one of the following questions, then prescribed burning, slash management, or fuel load management will not be done:
We do not minimize the contribution of smoke, any of it, to the global budget. The biosphere is smoke sensitive and may be under such change that climate changes may occur (e.g., warming). Within the management area we do not believe we can reduce smoke to zero. We do, however, seek to minimize the contribution to the global atmosphere and call upon others to adopt a similar strategy.
Prescribed Fire Guides
Prescribed fires when well managed, consume specific portions of a fuel profile in a safe, carefully controlled, and environmentally acceptable fashion to obtain conditions that achieve objectives. Guidelines for doing so include:
The planning elements include:
Experience in other fire management systems suggests that the following preparations be made to the extent that funds are available:
Cain (1985) having studied a natural loblolly area in Arkansas for 32 years concluded that prescribed fire or herbicides did not affect volume of trees. It did increase natural regeneration but this may be irrelevant if tree planting of optimal stock at optimal spacing is used. It seems likely that hardwood control after stand age 40 is meaningless but Cain seemed to encourage it in the face of his data on grounds unrelated to his study./ These he said:
"Even without growth response, periodic hardwood control in southern pine management is often warranted to improve stand accessibility for forest workers, to insure fuel hazard reduction in case of wildfires, to improve site conditions for natural pine regeneration, or to improve requirements for wildlife."
While he cited Grano's (1970) statement that understory vegetation can reduce the growth potential of pines, his study did not bear this out. In young stands it is said by Cain (1985) that understory vegetation reduces soil moisture for the trees, they do not comment on its effects on ground wind flow (air exchange) reduction and microclimatic humidity of the forest. Claims that hardwood control improves conditions for wildlife is far off the mark. It may increase deer forage but clearly reduces stand "structure", the prime determinant of bird diversity, and probably reduces amphibian and reptile diversity. Greater specificity about "wildlife" effects await improved phrasing as well as research.
Egging at al. (1980) presented a conceptual framework for integrating a fire management system into an environmental plan. As resources become available, this concept can be implemented in a GIS-based model.
Literature Cited
Althaus, I. A., and T. J. Mills. 1982. Resource values in analyzing fire management programs for economic efficiency. USDA For. Serv., pacific Southwest Forest Exp. Sta., Berkeley, CA 9 pp.
Arno, S. F., and J. K. Brown. 1989. Managing fire in our forest: time for a new initiative. J. For. 87(12):44-46.
Boring, L. R., J. J. Hendricks, and M. Boyd Edwards. 1991. Loss, retention and replacement of nitrogen associated with site preparation burning in southern pine-hardwood forests. p. 145-153 in S.C. Nodvin and T. A. Waldrop, eds. Fire and the environment: ecological and cultural perspectives. Conf. Proceedings, S.E. For. Exp. Sta., USDA, Ashville, NC 429 pp.
Bratlen, F. W., J. B. Davis, G. T. Flatman, J. W. Keith, S. R. Rapp, and G. S. Forey. 1981. Focus: a fire management planning system--final report. USDA Forest Serv., Pacific Southwest For. and Tange Exp. Sta. Gen. Tech. Rpt. PSW-49, Berkeley, CA 34 pp.
Chase, R. A. 1987. Planning the fire program for the third millennium, p. 61-65 in J. B. Davis and R. E. Martin. Proc. of the Symposium: Wildland Fire 2000. USDA For. Serv., Pacific Southwest Forest and Range Exp. Sta. Gen. Tech. Rpt. PSW-101, Berkeley, CA 257 pp.
Clayton, J. L. 1976. Nutrient gains to adjacent ecosystems during a forest fire: an evaluation. For. Sci. 22(2):162-166.
Cramer, O. P., and H. E. Graham. 1971. Cooperative management of smoke from slash fires. J. For. 69(6):327-331.
Dodge, M. 1972. Forest fuel accumulation--a growing problem. Sci 177:139-142.
Donaldson, B. G., and J. T. Paul. 1990. NFDRSPC: the national fire-danger rating system on a personal computer. USDA For. Serv. Southeastern For. Exp. Sta. Gen. Tech. Rpt. SE.61, Ashville, NC 49 pp.
Egging, L. T., and R. J. Barney. 1979. Fire management: a component of land management planning. Env. Manage. 3(1):15-20.
Egging, L. T., R. J. Barney, and R. P. Thompson. 1980. A conceptual framework for integrating fire considerations in wildland planning. USDA Forest Serv. Research Note INT-278, Intermountain Forest and Range Exp. Sta., Ogden, Utah 11 pp.
Fischer, W. C. 1984. Wilderness fire management guide. USDA For. Serv. Intermount. For. and Range Exp. Sta., Gen. Tech. Rpt. INT-171, Ogdon, Utah 56 pp.
Flatman, G. T. and T. G. Storey. 1979. Decision techniques for evaluating fire plans using FOCUS simulation. USDA Forest Serv. Res. Note PSW-338, Pacific Southwest For. and Range Exp. Sta., Berkeley, CA 6 pp.
Folkman, W. S. 1977. High-fire-risk behavior in critical fire areas. USDA For. Service Research Paper PSW-125/1977, Pacific Southwest Forest Exp. Sta., Berkeley, CA 12 pp.
Gilliam, F. S. 1991. The significance of fire in an oligotrophic forest ecosystem, p. 113-122 in S. C. Nodvin and T. A. Waldrop, eds. Fire and the environment: ecological and cultural perspectives. Conf. Proceedings, S.E. For. Exp. Sta., USDA, Ashville, NC 429 pp.
Halls, L. K., R. H. Hughes, and F. A. Peevy. 1960. Grazed firebreaks in southern forests. USDA For. Serv., Ag. Info. Bul. 226, Washington, DC 8 pp.
Johnson, V. J. 1984. Prescribed burning: requiem or renaissance? J. Forestry 82(2): 82-90.
Johnson, V. J. 1982. Ambivalent effects of fire in eastern broadleaf forests. Proc. of the 1982 Conf. of the SAF, Cincinnati, Ohio p 153-156.
Kozlowski, T. T., and C. E. Ahlgren, Eds. 1974. Fire and ecosystems, Academic Press, New York, NY 542 pp.
Lotan, J. E. 1976. Fire management perspective: USDA forest Service, Western Wildlands, Summer, 1977.
McKee, W. H., Jr. 1991. Long-term impacts of fire on coastal plain pine soils, p. 405-413 in Nodvin and T. A. Waldrop, eds. Fire and the environment: ecological and cultural perspectives. Conf. Proceedings, S. E. For. Exp. Sta., USDA, Asheville, NC 429 pp.
Mutch, R. W. 1976. Fire management and land use planning today: tradition and change in the Forest Service. Western Wildlands, Winter, p. 13-19.
Mutch, R. W., and G. S. Briggs. 1976. The maintenance of natural ecosystems: smoke as a factor, p 255-281 in Air quality and smoke from urban and forest fires. Nat. Acad. Sci. Symposium (1975), Washington.
Pharo, J. A. 1976. Aid for maintaining air quality during prescribed burns in the south. USDA For. Serv. Res. paper SE-152, S. E. Forest Exp. Sta., Ashville, NC
Roussopoulos, P. J. and V. J. Johnson. 1975. Help in making fuel management decisions. USDA For. Serv. North Central Forest Exp. Sta. Res. Paper N C-112, St. Paul, MN 16 pp.
Rothermel, R. C. 1980. Fire behavior systems for fire management, p 58-64 in Proc. 6th Conf. on Fire and Forest Meteorology, Seattle, WA Soc. Am. For., Washington, DC
Schweitzer, D. L., E. V. Andersen, and T. J. Mills. 1982. Economic efficiency of fire management programs at six National Forests. (with revisions) USDA Forest Serv., Res. Paper PSW-157, Pacific Southwest For. Exp. Sta., Berkeley CA 29 pp.
Simard, A. J. and L. R. Donoghue. 1987. Wildland fire prevention today, intuition--tomorrow, management p. 187-198 in J. B. Davis and R. E. Martin. Proc. of the Symposium: Wildland Fire 2000. USDA For. Serv., Pacific Southwest Forest and Range Exp. Sta. Gen. Tech. Rpt. PSW-101, Berkeley, CA 257 pp.
Tangren, C. D. 1976. Smoke from prescribed fires, Forest Farmer 35(10):6-7.
USDA. 1976. Southern forestry smoke management guidebook. USDA Forest Service Gen. Tech. Report SE-10, Macon, GA 140 pp.
VanLear, D. H. 1991. Fire and oak regeneration in the Southern Appalachians, p. 15-21 in Nodvin and T. A. Waldrop, eds. Fire and the environment: ecological and cultural perspectives. Conf. Proceedings, S. E. For. Exp. Sta., USDA, Asheville, NC 429 pp.
VanLear, D. H., and T. A. Waldrop. 1989. History, uses, and effects of fire in the Appalachians. USDA For. Serv. Southeastern For. Exp. Sta. Gen. Tech. Rpt. SE-54, Ashville, NC 24 pp.
Various authors. 1976. Teton Wilderness fire management plan. Budget-Teton National Forest, Jacobson, Wyoming (variously pages, approximately 200 pp).
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