Fire Effects on Vegetation and Succession 1

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Malcolm J. Zwolinski2

AI though land managers today effects and adaptive characteristics, A plant's ability to withstand fire are expected to predict the short- and and to examine the past and present and subsequent heat effects depends long-term ecological effects of differ concepts of ecological succession fol upon its heat tolerance and its fire ent management alternatives, predic lowing disturbance by fire. The ef resistance. Heat tolerance is the abil tions of fire effects on vegetation are fects of fire on specific southwestern ity of plant organs and tissues to particularly difficult due to the wide vegetation types and resource values withstand elevated temperatures, variability in fire characteristics and will not be treated here but will be whereas fire resistance is the ability vegetation complexes. There is defi covered in considerable detail by of a plant to survive the passage of a nitely a need for better and more reli later. authors. fire. able predictions on how various management options affect plant communities and other ecosystem Effects of Fire on Vegetation Heat Tolerance components. These predictions must be incorporated into fire manage Fires in natural ecosystems con A plant is directly injured or killed ment decision-making and policies sume vegetative material, produce when the temperature of internal liv (Kessell 1981). residual mineral products, and raise ing cells is raised to a lethal level. Fortunately, the situation is im temperatures for short periods. In Precise information on the tempera proving. The past decade has pro many fires, plant response depends tures necessary to kill living plant vided a number of significant ad more on the direct and indirect ef tissues is lacking (Brown and Davis vances in our knowledge of and abil fects of higher temperatures than on 1973). Baker (1950) has stated that ity to predict fire effects and post-fire available fuel or release of products. the heat tolerance of plant proto succession. A better understanding Some heat effects may be immediate plasm appears to be the same for all of adaptive characteristics of individ and easily observed, i.e., the killing species. This suggests that, although ual plant species and basic succes of plant tissue; other effects may be protoplasm coagulation defines le :·,.·' sional processes, coupled with the delayed and more difficult to detect, thality for the individual cell, the dif continued developments in fire be such as damage leading to increased ferences in internal heat effects is due havior models and geographic infor insect and disease susceptibility. This largely to differences in insulation mation system data bases, is already variability can cause problems for from heat sources. having an impact on fire manage managers faced with the task of pre A temperature of 60°C (140°F) for ment decisions. dicting changes in plant succession one minute is often given as the le The purpose of. this paper is to and ecosystem dynamics. thal temperature required to kill briefly summarize the general effects Any woody or herbaceous plant plant tissue. However, Wright (1970) of fire on vegetation, including heat can be killed by a fire of sufficient points out that the temperature at duration and intensity. It is with fires which death of plant tissue occurs is of lower intensity or shorter dura- largely dependent upon the tissue 1 Panel paper presented at the confer ence, Effects of Fire in Management of -tion, where only a part of the plant moisture content, where tissues with Southwestern Natural Resources (Tucson, community is killed, that the inher higher moistures are killed at lower AZ, November 14-17, 1988). ent ability of individual plants to temperatures and shorter time inter 2Professor of Watershed Management, withstand or resist fire becomes sig vals. It is possible that a steaming ef University of Arizona, Tucson, Arizona 85721 nificant. fect may be responsible for increased

18 heat susceptibility in plants with which result in vegetative sprouting, the year, fire frequency, and fire in higher moisture contents. and those which enhance reproduc tensity. Not only is heat tolerance depend tion, such as (2) fire-stimulated flow Fire-stimulated flowering. ent on tissue moisture content, but it ering, (3) seed storage on the plant Among fire-resistant plants, the phe also varies for different plant parts. and fire-stimulated dehiscence, and nomenon of fire-stimulated flower For example, seeds are known to be (4) seed storage in the soil and fire ing has been observed (Chandler and very tolerant of heat (Daubenmire stimulated germination (Gill1981). others 1983, Gill1981). Although not 1968). Chaparral species with hard, Bark thickness and protected widely reported in the western thick seed coats are able to tolerate buds.-The insulating qualities of United States, a number of observa temperatures of 125° to 150°C (260° to bark are well recognized. Reifsnyder tions have been made in Australia, 300°F) (Sampson 1944). Wright and and others (1967) have stated that the Israel, New Zealand, and South Af Bailey (1982) indicate that seeds cov primary factor in determining rica. This trait appears to be most fre ered slightly with soil can be insu whether a tree is fire resistant or not quently associated with the mono lated from the effects of a moderate appears to be bark thickness. Wright cotyledons, especially the amaryllis, to intense fire. Furthermore, they and Bailey (1982) report that trees grass, lily, and orchid families. speculate that grass fires would suffer very little heat damage if the The mechanisms responsible for probably have little or no effect on bark thickness is 1.0 to 1.3 em. Many the triggering of flowering by fire are the mortality of dormant seeds, even plant protective mechanisms vary still unknown. The results, however, if the seeds were lying on the soil during growth and development so are that prolific flowering is followed surface. Roots, stems, and foliage that susceptibility to fire damage by increased seedling establishment. also exhibit variations in heat toler may also change with age. In gen This may be a consequence of greater ance, as can the presence of salts, eral, bark tends to be quite thin in seed set, lower on-plant seed preda sugars, pectins, and other plant tis small trees, considerably thicker at tion, or lower predation of seeds fol sue substances. maturity, and declines in thickness lowing dispersal (Gill1981). Chan with senescence. dler and others (1983) speculate that Plant survival following fire can either a change in diurnal tempera Fire Resistance frequently be attributed to the loca tures following fire or an increase in tion of meristems and the protection the amount of light reaching the soil A plant's ability to survive or re buds receive from reaching lethal may cause heating of the floral repro cover from the passage of a fire, de temperatures. Packham (1970) noted ductive organs and induce flowering. fined as fire resistance, is dependent that the amount of rising convective The removal of shrubs could also upon its food reserve levels and the heat from a surface fire is three times promote more effective pollination of presence or absence of fire adaptive that of radiated heat. The exposed certain species by insects and wind. traits, i.e., protection of growing ar location of terminal and lateral apical Seed retention and fire-stimu eas, resprouting, germination of dor buds of many shrubs make them lated dehiscence.-For many shrubs mant seeds, etc. Plants are more sus highly susceptible to top-killing from and trees~ retention of seeds on the ceptible to damage from fire during rising convective heat, whereas sur plant and stimulation of dispersal is flowering and seed formation or dur face and subterranean buds are well an important mechanism for survival ing periods of active growth when protected against major heat inputs. in fire-prone environments. Two ex carbohydrate reserves are low. Since The basal meristems of a number of amples of tree species that possess seasonal trends in food reserves vary grass and forb species provide a dis this trait are jack pine (Pinus considerably between plant species, tinct fire survival advantage. Basal banksiana) and lodgepole pine (Pinus burning at any particular season can sprouting may be common in shrubs contorta). A number of other pine be more detrimental for some species after fire has destroyed the foliage. species have cones that dehisce (split than for others. Sprouting is thought to be an ancient open) after fire or under the effects of adaptation which occurs when the fire, a trait known as serotiny. The foliage is removed by an external cone scales of these pines are held Fire Adoptive Traits agent (Chandler and others 1983). closed by a resinous or waxy mate While the leaves are alive, an inhibit rial sensitive to high temperatures. In fire ecology literature, four fire ing factor prevents bud activity, but As fire passes and heat melts the res adaptive traits of plants have been when the foliage is killed the inhibi ins, the cone scales exfoliate and given special attention. These traits tion disappears and the dormant seeds are released. Lodgepole pine is are described as those which enhance buds begin sprouting. Resprouting particularly interesting because its survival during a fire, such as (1) after fire appears to be related to the cones can vary from serotinous to bark thickness and protected buds age of the plant, stem size, season of freely dehiscent (Brown 1975; Lotan

19 1975, 1976). In stands where fires are The authors concluded that heat is peated fires while those that produce frequent, serotinous cones are com not required for germination, but seed are favored by infrequent fires mon, whereas cones are freely dehis germination is stimulated by the re (Keeley 1981). · cent in forests where fire is less fre moval' of the inhibiting ligneous ex Understanding the effect of fire quent. Lotan (1975) also reported tracts. The degree of seed coat inhibi intervals is important because it can that young lodgepole pine trees tend tion removed is dependent upon the significantly affect the survival to have open cones while older trees intensity and duration of heat expo probability of an individual, popula possessed either open or closed sure. When woody plants return, the tion, or species. In general, a pattern cones. inhibition becomes reestablished; of less frequent fires burning with When seeds from serotinous cones however, the seeds remain viable un higher surface temperatures due to are released by fire, they often fall on til another fire takes place. increased fuel accumulations, and a favorable seedbed. The ash and Gill (1981) refers to these four vice versa, has been recognized. Fire minerals provide nutrients while the vegetation adaptations as the "classi regimes, then, modify the evolution lack of overstory foliage increases the cal" fire traits. He points out that of plants and any changes in these amount of sunlight reaching the soil there are other developmental pat fire regimes will precipitate a change to assist in seedling germinati~n and terns of plant species which could be in the floristic composition and struc ~ .·.: _.,-': . growth. · considered fire adaptations. Men ture of a vegetative type. Seed storage in the soil and fire tioned as possibilities are seed burial, The season of fire occurrence is a stimulated germination.-The stor plant longevity, chemical composi very important factor affecting plant age of seeds in the soil and stimula tion, time to first flowering, and pat survival and flowering. Frequently, tion of their germination by fire can terns of leaf shedding. Many adap substantial fire effects differences can be seen as an adaptive trait. Seed ger tive mechanisms are able to facilitate be observed between spring and fall mination in recently burned plant the reproduction or survival of plant bums. Spring fires tend to damage communities can usually be attrib spe~ies in fire-prone environments. annual grasses that emerge following uted to the release of seeds retained winter rains and have not had the by the plants or to the germination of opportunity to produce seed. On the seeds stored in the soil from past Fire Characteristics other hand, many perennial species years. Some transport of seeds to the are still_dormant during a spring fire burned area from sources in adjacent Chandler and others (1983) state and could resprout later in the sea unburned sites is also possible. that adaptive traits have been consid son (Wright 1969, 1974). Hardseededness is a term applied ered in relation to the occurrence of a The size of the area burned by a to seeds with a physical barrier to single fire, but, in actuality, an indi stand-consuming fire can influence germination, commonly typified by vidual plant may be exposed to sey recolonization if plants are unable to the lack of imbibition, swelling, and eral fires, each with different fire regenerate by sprouting. Seed carri softening when exposed to water characteristics and fire effects. To de ers, such as wind or animals, may (Gill1981). However, when the seed termine the significance of adaptive not provide adequate distribution of coat is scarified, germination does traits consideration must also be seeds if the burned area is extensive. occur. A number of woody and her given to the life cycle of the species Vegetative responses to intensity baceous species, perennials, and an and fire regimes to which the species and duration of heating vary consid nuals exhibit this trait. Fire is one of is subjected. erably depending on the natural role the mechanisms capable of scarifying Fire frequency determines the of fire in an ecosystem. With fire-sen seeds and breaking seed dormancy. vegetative composition of an area by sitive species, a low~intensity fire Similar results can be achieved by the selecting species which will continue may be very damaging, while a mod movement of seeds in ephemeral to occupy a site. A species can be erate- to high-intensity fire in a vege streambeds and softening of seed af removed if fire occurs too often, too tative type dependent upon fire may ter passage through birds and ani early, or too late in its life cycle. For stimulate reproduction and cause mals (Gill1981). instance, a non-sprouting species little change in floristic composition. Research by Muller and others may be lost if fire occurs before seed Fire intensity is one of the more diffi (1968) on the allelopathic conditions has been produced, or if fire occurs cult fire characteristics to assess. in California chaparral indicates that after the species has died and the Some observers rely on the visual profuse flowering and appearance of - seed pool is unavailable (Chandler post-fire changes evident on vegeta herbaceous species after fires is due and others 1983). Two strategies typi tion or soil, others install tempera to the destruction of a chemical in cally characterize the response of dif ture sensors or attempt to correlate hibitor produced by the woody plant ferent species to fire frequencies - intensity with flame lengths using cover and deposited on buried seeds. those that sprout can withstand re- different indices.

20 A fire that creates high surface Two types of succession are often nities can also be attributable to site temperatures for a long duration can recognized -primary and secon or other environmental conditions. result in heat penetrating into the dary .. Primary succession is the de This has led to a number of addi surface soil. The survival of subterra velopment of communities on newly tional definitions of climax attributes nean organs, i.e., roots, rhizomes, exposed bare areas which have not such as polyclimax, subclimax, and seeds, is dependent on the depth previously supported vegetation. Pri physiographic climax, edaphic cli of heat penetration. If penetration is mary succes~ion, also known as auto max, disclimax, preclimax, and extensive, organs are killed and rees genic or self-induced succession, postclimax. · tablishment of the species will be dif starts with a pioneer stage (usually Notwithstanding the debate on ficult. A low intensity fire does not mosses and lichens) and progresses climax, ecologists acknowledge that destroy these organs which aJlows to larger and taller species, each cre some ecosystem changes accompany the vegetation to become rees ating a microclimate or soil condition the successional growth and matura tablished on the site quickly~ which induces the emergence of a tion of vegetational stages. For ex new community and the loss of the ample, there appears to be a progres old. sive increase in community complex Effects of Fire on Success.ion Secondary succession is the se ity and diversity from early to ma quence of vegetation development on ture stages, an increase in the total The preceding discussion was spe areas which have supported vegeta biomass and gross productivity, and cifically directed to heat effects, fire tion but now vegetation has been de an increasing development and adaptive traits, and fire characteris stroyed, in part or in total, by an maturation of soils. tics. This information can now lead agent such as fire, flood, windstorm, to an examination of ecological suc etc. The term allogenic (externally cession in a fire-prone environment. induced) is often used with secon Fire Disturbances Before considering the· present-day dary succession because changes are concepts of fire-disturbed succession, precipitated by forces independent of The classical concept of succession it is important to look back ~t the the community itself. Secondary suc subscribes that, following a distur early or classical version of succes cession can appear at any stage of bance, such as fire, the present com sion and to see why it fails in dis primary succession and, theoreti munity disappears and is replaced by turbed ecosystems. · cally, causes a retrogression or reset an earlier vegetation type which re ting of succession back to an earlier sults in a retrogression or backing up stage. The essential distinction be of succession. Succession then moves Classicai.Succession tween primary and secondary suc forward through the intermediate or cession is that pioneer communities seral stages to the stable, climax com The classical definition of succes of a secondary succession receive the munity. This classical succession has sion is simply the replacement of the benefit of soil already in place. been described in the literature as the biological community of an. area by Probably one of the most confus facilitation model (because of its em another community. Classkal Cle ing aspects of classical ecological suc phasis on changes within succes mentsian succession can be described cession is the concept of a climax sional areas facilitating the establish as (1) an orderly process of commu community. A postulate advanced ment of new species), the relay floris nity change which is reasonably di by Clements (1936) and his followers tics inodel (due to the replacement or rectional and_predictable, (2) result states that community succession relay sequence of successional stages ing from the modification of the leads to a climax and that the con or seres), or the single pathway physical environment by the present cept of succession cannot be sepa model where succession follows a community which creates conditions rated from that of climax. Clements predictable sequence of steps (Con suitable for the establishment of an felt that with sufficient time and nell and Slatyer 1977, Egler 1954). other community, and (3) ultimately competition, an undisturbed plant Not all successions necessarily reaching a biologically stable ecosys community would approach the proceed stepwise through to a climax tem stage (climax community) (Cle same species composition and struc community. If disturbal}ces, such as ments 1916, 1936). ture in a given climatic region .. This fire, are part of the natural environ Clements has·also identified the monoclimax or climatic climax con ment of a plant community, the.n the successional development of vegeta cept placed only secondary impor term climax loses meaning since all tion as a sequence of five processes: tance on other site factors such as species that persist are climax spe immigration, establishment, site soil, topography, or repeated distur cies. Climax implies stability; how modification~ competition, and eco bances. Over time, ecologists recog ever, plant cominunities cannot be system stabilization. nized that stable vegetative commu- completely stable. With different 21' ages and lifespans, there are weak sprouted vegetatively from ing widely acknowledged that the and overmature individuals that dis organs surviving the fire. properties of individucil species are appear and are replaced. Openings, Therefore, it is not surprising one of the key factors in determining either natural or human-caused, al that replacement sequences successional patterns in fire-adapted low the establishment of new indi following fire tend to be re communities. Noble and Slatyer viduals or species. Thus, communi producible and often lead to (1977, 1980, 1981) and Noble (1981) ties are characterized by continual development of communities have provided the foundation for change rather than by stability. It is similar to those existing be much of today' s work on plant adap interesting to note that Patterson fore fire (initial floristic com tive traits and post-fire succession. (1986) has recommended that the position) or existing on These authors sought to identify a word "climax" be stricken from for nearby undisturbed areas. small number of attributes which are est terminology. He argues that Cle vital to terrestrial, higher plant com mentsian climax theory is known to 2. Shortly after fire, there is a munity species which occur in areas be based on assumptions that cannot surge of recruitment and re subject to recurrent fires. They devel be met, and that continual changes in growth under conditions of oped a "multiple pathways" model time and space make ecosystems dy low competition for site re for predicting major shifts in species namic instead of stable. sources. composition and dominance in fire As the failure of classical succes prone ecosystems w:hich is based on sion concepts to describe vegeta 3. There is a slowing in recruit selected plant "vital attributes." tional changes resulting from distur ment following the initial Three main groups of species at bances became more apparent, scien surge as individuals become tributes which are vital in a vegeta tists began to propose other models established and are more dif tion replacement sequence have been of succession. In 1977, Connell and ficult to displace. recognized. These are (1) method of Slatyer suggested two additional persistence (the method of species pathways of succession. They identi . 4. Further recruitment of new arrival after, or persistence during, a fied these as the tolerance and the species may be facilitated by fire), (2) mechanisms for establish inhibition models; both were at prior occupancy, but it may ment (attribute associated with the tempts to explain the site occupancy also be restricted or inhibited site conditions in which the species of certain species following distur by present occupants. become established and grow to ma bances. The tolerance model de turity), and (3) critical life stages 5. In the absence of further scribes the situation in which later (time needed for the species to reach fires, species that are long species are successful whether or not critical periods in its life history, i.e., lived and those that can re earlier species have preceded them. reproduction, maturity, senescence, generate and grow under an The inhibition model considers the extinction). adult canopy will become condition where later species cannot In recent years increasing numbers dominant. grow to maturity in the presence of of authors have reported the use of earlier ones. Although these two For understanding successional the vital attributes approach to de models provide some insight on spe pathways following fire, evaluation scribe successional changes following cies establishment, they did not deal of responses by individual plant spe fire (Hobbs and others 1984, Noste ' ~ '· , . effectively with species changes cies leading to community develop and Bushey 1987, Rowe 1983). Some being observed following fire distur ment may be considerably more use excellent fire ecology information bances. ful than the community replacement and fire management guidelines us As more information on fire dis approach of Clements. Fire-induced ing species attributes and fire charac turbances and succession became succession is related to the adapta teristics for specific forest habitat available, Noble and Slatyer (1981) tions possessed by individual plant types in Idaho and Montana have stated that several generalizations species to colonize, grow, and sur been published (Crane and Fischer could be made. These were: vive. Therefore, specific life-history 1986, Fischer and Clayton 1983, characteristics of key species in a par Kessell and Fischer 1981). 1. Species composition immedi ticular community can be used to de Although it is evident that this ately following a fire is de scribe successional patterns which method is providing managers with pendent upon propagules follow fires of varying intensities and a more realistic prediction of post (reproductive structures) frequencies. fire succession, there are situations which have arrived from ad Fire is now recognized as one of where its application is difficult. For jacent areas, have persisted the most common disturbances of example, the wide variability in cone through the fire, or have re- natural ecosystems and it is becom- serotiny for lodgepole pine has direct

22 applicability to its reproductive suc and after fire by researchers and successional sequences with ecologic cess after fire. Some difficulties also managers together may be most and managerial concerns. arise because of the lack of vital at valuable. Researchers and managers The challenge of the 1990's will be tribute information on key plant spe need to determine precisely what in to continue to build upon this knowl cies. It is recognized that this ap formation is required to do the job edge base and to expand application proach works best for forest and (USDA FS 1981). Although some re to include how fire disturbances and brush overstories, but little attention searchers disdain the concept of their management affect other terres has been given to understory herba "good enough," often managerial ob trial and aquatic community compo ceous species. As additional data on jectives can be adequately met by nents. Fire impacts on water quality, plant adaptations, life histories, and procedures and models that are nei nutrient cycles, ecosystem dynamics site-specific fire characteristics be ther the ''best" nor the "most com and energetics, fish and wildlife, fuel come available, the use of the mul plete." The cost of improving or ex complexes, and soil properties are tiple pathway vital attributes model panding such procedures may not be directly and indirectly related to flo of succession will become a more financially justifiable to the manager ristic changes and successional pat v.aluable tool for the land manager in or the agency. A program of coopera terns. Additional information on fire prone areas. tion and communication between re these components in a fire disturbed search and management will yield community will, undoubtedly, sub greater benefits than individual ef stantially enhance the value and ap Management Implications forts. plicability of fire management plans. An example of such cooperative The land manager attempting to efforts is the development of a Fire predict the effects. of fire on vegeta Effects Information System (FEIS), a Literature Cited tion and subsequent successional se new computer-based storage andre quences is facing a difficult task. This trieval system. This FEIS is being de Baker, F. S. 1950. Principles of individual is being asked to integrate veloped at the Intermountain Fire silviculture. 2nd Edition. information which ranges from plant Sciences La bora tory in Missoula by McGraw-Hill Book Co., New heat tolerances, fire resistances, and Forest Service prescribed fire and fire York. plant adaptations, to specific fire and effects research personnel and the Brown, A. A.; Davis, K. P. 1973. For weather characteristics, into a rea Computer Science Department at the est fire: control and use. 2nd Edi- sonably comprehensive and mean University of Montana. The Bureau . tion. McGraw-Hill Book Co., New ingful fire management plan. The of Land Management and the Na York. 686 p. magnitude of the task is readily ap tional Park Service have provided Brown, J. K. 1975. Fire cycles and parent. Thus, a major function of this support for the project. The purpose community dynamics in lodgepole paper was to provide an overview of of the system is to provide land man pine forests. Proc. Symp. Manage. fire effects and their relationship to agers easy access to up-to-date infor Lodgepole Pine Ecosystems. succession and to furnish managers mation on fire effects in plant com Wash. State Univ. Coop. Ext. Serv. with information on changes and munities and associated individual Publ.: 429-456. new approaches for use in decision plant and animal species. Managers Chandler, C.; Cheney, P.; Thomas, P.; making. interested in this system may wish to Trabaud, L.; Williams, D. 1983. One of the more important points contact the Intermountain Fire Sci Fire in forestry. Vol. I. Forest fire for today' s land managers who deal ences Laboratory, the Boise Inter behavior and effects. J. Wiley & with fire is to recognize that the ap agency Fire Center, BLM State Of Sons, New York. 450 p. plication of classical succession con fices in Idaho, Colorado, Nevada, Clements, F. E. 1916. Plant succes cepts to predict post-fire vegetation and Oregon, or personnel at Wind sion: an analysis of the develop patterns is not appropriate. There Cave National Park. ment of vegetation. Carnegie Inst. fore, managers should become as In the coming years continued ad Publ. 242. Washington, D. C. familiar as possible wHh the individ vances will be made in our under 512 p. ual plant species in their area and, standing of and ability to predict Clements, F. E. 1936. Nature and particularly, try to determine what post-fire plant succession. Work has structure of the climax. J. Ecol. 24: attributes these species have to sur already progressed on several fronts, 252-284. vive or persist following fire. Some including the knowledge of basic Connell,}. H.; Slatyer, R. 0. 1977. of this latter information may be successional processes, the adaptive Mechanisms of succession in natu available in the literature but, ulti characteristics of species populations, ral communities and their role in mately, close field observations and the effects of fire intensity and perio community stability and organiza records of plant responses during dicity, and the ability to integrate tion. Amer. Nat. 111:1119-1144.

23 Crane, M. F.; Fischer, W. C. 1986. Pine Ecosystems. Wash. State Reifsnyder, W. E.; Herrington, L. P.; Fire ecology of the forest habitat Univ. Coop. Ext. Serv. Publ.: 471- Spalt, K. W. 1967. Thermophysical types of central Idaho. Gen. Tech. 495. properties of bark of shortleaf, Rep. INT-218, Ogden, UT. U.S. Lotan, J. E. 1976. Cone serotiny. Fire longleaf, and red pine. Yale Univ. Department of Agriculture, Forest relationships in lodgepole pine. School of For. Bull. No. 70. Service, Intermountain Forest and Tall Timbers Fire Ecol. Conf. Proc. Rowe, J. S. 1983. Concepts of fire ef Range Experiment Station. 86 p. 14: 267-278. fects on plant individuals and spe Daubenmire, R. 1968. Ecology of fire Muller, C. J.; Hanawalt, R. B.; cies. In: Wein, R. W. and D. A. in grasslands. Adv. Ecol. Res. 5: McPherson, J. K. 1968. Allelopa MacLean, eds. The Role of Fire in 209-266. thic control of herb growth in the Northern Circumpolar Ecosys Egler, F. E. 1954. Vegetation science fire cycle of California chaparral. tems. John Wiley & Sons, New concepts. I. Initial floristic compo Bull. Torr. Bot. Club 95: 225-231. York: 135-154. sition, a factor in old-field vegeta Noble, I. R. 1981. Predicting succes Sampson, A. W. 1944. Plant succes tion development. Vegetatio 4: sional change. In: Fire Regimes sion on burned chaparral lands in 412-417. and Ecosystem Properties. Gen. northern California. Calif. Agric. Fischer, W. C.; Clayton, B. D. 1983. Tech. Rep. W0-26, Washington, D. Exp. Sta. Bull. No. 685. Berkeley, Fire ecology of Montana forest C. U. S. Department of" Agricul CA. habitat types east of the Continen ture, Forest Service: 278-300. U.S. Department of Agriculture, For tal Divide. Gen. Tech. Rep. INT- Noble, I. R.; Slatyer, R. 0. 1977. Post est Service. 1981. Effects of fire on 141, Ogden, UT. U.S. Department fire succession of plants in Medi flora: A state-of-knowledge re of Agriculture, Forest Service, terranean ecosystems. In: Environ view. Gen. Tech. Rep. W0-16. Intermountain Forest and Range mental Consequences of Fire and Washington, D. C. 60 p. Experiment Station. 210 p. Fuel Management in Mediterra Wright, H. A. 1969. Effects of spring Gill, A.M. 1981. Fire adaptive traits nean Ecosystems. Gen. Tech. Rep. burning on tobosa grass. J. Range of vascular plants. In: Fire Re W0-3, Washington, DC.l:J. S. De Manage. 22:425-427. gimes and Ecosystem Properties. partment of Agriculture, Forest Wright, H. A. 1970. A method to de Gen. Tech. Rep. W0-26, Washing Service: 27-36. termine heat-caused mortality in ton, D. C. U.S. Department of Ag Noble, I. R.; Slatyer, R. 0. 1980. The bunchgrass. Ecol. 51:582-587. riculture, Forest Service: 208-230. use of vital attributes to predict Wright, H. A. 1974. Range burning. J. Hobbs, R. J.; Mallik, A. U.;'Giming successional changes in plant com Range Manage. 27:5-11. · ham, C. H. 1984. Studies on fire in munities subject to recurrent dis Wright, H. A.; Bailey, A. W. 1982. Scottish heathland communities. J. turbances. Vegetatio 43:5-21. Fire ecology- United States and Ecol. 72: 963-976. Noble, I. R.; Slatyer, R. 0. 1981. Con Southern Canada. John Wiley & Keeley, J. E. 1981. Reproductive cepts and models of succession in Sons, New York. 501 p. cycles and fire regimes. In: Fire vascular plant communities sub Regimes and Ecosystem Proper ject to recurrent fire. In: Fire and ties. Gen. Tech. Rep. W0-26, the Australian Biota. Australian Washington, D. C. U.S. Depart Acad. of Sci., Canberra City, Aus ment of Agriculture, Forest Serv tralia: 311-335. ice: 231-277. Noste, N. V.; Bushey, C. L. 1987. Fire Kessell, S. R. 1981. The challenge of response of shrubs of dry forest modeling post-disturbance plant habitat types in Montana and succession. Environ. Manage. 5 Idaho. Gen. Tech. Rep. INT-239, (1): 5-13. . Ogden, UT. U.S. Department of Kessell, S. R.; Fischer, W. C. 1981. Agriculture, Forest Service, Inter Predicting postfire plant succes mountain Forest and Range Ex sion for fire management plan periment Station. 22 p. ning. Gen. Tech. Rep. INT-94, Packham, D. R. 1970. Heat transfer Ogden, UT. U.S. Department of above a small ground fire. Aust. Agriculture, Forest Service, Inter For. Res. 5: 19-24. mountain Forest and Range Ex .Patterson, W. A. III. 1986. A ''New periment Station. 1.9 p. Ecology'' - Implications for mod Lotan, J. E. 197~. The role of cone se ern forest management. J. For. 84 rotiny in lodgepole pine forests. (2): 93. Proc. Symp. Manage. Lodgepole