Health Perspect. Diaz, J. Economic Impacts of Wildfire. Southern Fire Exchange. Fact Sheet Dudley, W. Forest reservations: with a report on the Sierra reservation, California. Sierra Club Bull. East Bay Regional Parks Evett, R. Phytolith evidence for a grass-dominated prairie landscape at Quiroste Valley on the central coast of California. Fadadu, R. Association of wildfire air pollution and health care use for atopic dermatitis and itch.
JAMA Dermatol. Fairfax, S. American forestry professionalism in the Third World: some preliminary observations. Fargione, J. Land clearing and the biofuel carbon debt. Fernandes, P. Characteristics and controls of extremely large wildfires in the western Mediterranean Basin. Biogeosciences , — A review of prescribed burning effectiveness in fire hazard reduction. Fire 12, — Ferranto, S. Forest and rangeland owners value land for natural amenities and as financial investment.
Flagg, J. Forest Management Task Force Fried, J. Managing for naturalness at Mt. Diablo state park. Germano, D. Effects of grazing and invasive grasses on desert vertebrates in California. Global Fire Data Global Fire Emissions Database. Godsey, S. Energy, economics, and the decline of transhumance, Geogr. Goulden, M. California forest die-off linked to multi-year deep soil drying — Green, L. Goat control of brush regrowth on southern California fuelbreaks.
Rangelands Archives 1, — Hagerty, C. Prescribed Burn Associations are one answer to California's megafires: community groups seek to fill in the gap left by overtaxed agencies. Sierra Magazine. Haikerwal, A. Impact of fine particulate matter PM 2. Heart Assoc. Harris, J. Ecological restoration and global climate change. Hastings, M. Restoration Management of Northern Oak Woodlands.
Heady, H. Vegetational Changes in Yosemite Valley. Washington, DC: U. Department of the Interior. Heizer, R. Hobbs, R. Managing the whole landscape: historical, hybrid, and novel ecosystems.
Huntsinger, L. Use of livestock grazing to manage understory vegetation in a California silvo-pastoral system: effects of season, intensity, and frequency of grazing. Disputing Environmental Change in the Drylands , eds R. Behnke and M. Mortimore Berlin; Heidelberg: Springer , — In California? Rangelands and livestock in the Golden State. Rangelands 36, 4— Transhumance and pastoralist resilience in the western United States. Policy, Pract. A forest for the trees: forest management and the Yurok environment, to Indian Cult.
Ecosystem services may be better termed social ecological services in a traditional pastoral system: the case of California Mediterranean rangelands at multiple scales. Ingram, R. Barros and E. Jackson, L. Ecological origins of California's Mediterranean grasses.
Joffre, R. The dehesa system of southern Spain and Portugal as a natural ecosystem mimic. Johnston, F. Estimated global mortality attributable to smoke from landscape fires. Keele, D. Forest Sci. Keeley, J. Native American impacts on fire regimes of the California coastal ranges. Fire and grazing impacts on plant diversity and alien plant invasions in the southern Sierra Nevada. Twenty-first century California, USA, wildfires: fuel-dominated vs. Fire Ecol. Kocher, S.
Governance of land use planning to reduce fire risk to homes Mediterranean France and California. Koman, P. Mapping modeled exposure of wildland fire smoke for human health studies in California. Atmosphere Kosco, B. Effects of cattle and deer on regenerating mixed conifer clearcuts. Range Manage. Kousky, C. Issue Brief. Kramer, H. High wildfire damage in interface communities in California.
Fire 28, — Lake, F. Fire Manag. Today 79, 30— Langmann, B. Vegetation fire emissions and their impact on air pollution and climate.
Larvie, K. California Forestry Note No. Lasaux, M. University of California Cooperative Extension. Launchbaugh, K. Legislative Analyst's Office Improving California's Forest and Watershed Management. Leiberg, J. Liang, Y. Chemical composition of PM 2. Lightfoot, K. Anthropogenic burning and the Anthropocene in late-Holocene California. Holocene 25, — Loud, L. Lovreglio, R. Goat grazing as a wildfire prevention tool, a basic review.
Lubetkin, K. Climate and landscape drive the pace and pattern of conifer encroachment into subalpine meadows. Macon, D. The art and science of targeted grazing—a producer's perspective. Rangelands 36, 31— Marks-Block, T. McBride, J. Invasion of grassland by Baccharis pilularis DC. Plant succession in the Berkeley Hills, California. The failure of planning to address the urban interface and intermix fire-hazard problems in the San Francisco Bay Area.
McKelvey, K. Projected Trends in Owl Habitat, Chapter Merriam, K. Fuel breaks affect nonnative species abundance in Californian plant communities. Miller, C. Gifford Pinchot and the Making of Modern Environmentalism. Boulder, CO: Island Press. Miller, R. Barriers and enablers for prescribed burns for wildfire management in California.
Minnich, R. Batema, L. Fernandez, R. Carson Dordrecht: Springer , — Moore, D. Population health effects of air quality changes due to forest fires in British Columbia in Public Heal. Moreira, F. Wildfire management in Mediterranean-type regions: paradigm change needed. Moreno, J. Fire intensity and herbivory effects on postfire resprouting of Adenostoma fasciculatum in southern California chaparral. Oecologia 85, — doi: Morrow, J. Hufford Family Archives.
Muir, J. My First Summer in the Sierra. Boston, MA: Houghton Mifflin. Nader, N. Planned herbivory in the management of wildfire fuels. Rangelands 29, 18— Naeher, L. Woodsmoke health effects: a review. National Interagency Fire Center Narvaez, N. Potential contribution of Quercus durata and Adenostoma fasciculatum supplemented with Medicago sativa on intake and digestibility in sheep and goats. Agroforest Syst. National Oceanic and Atmospheric Administration California Average Temperature January-December.
Annual Time Series. Naudts, K. Europe's forest management did not mitigate climate warming. New York Times North, M. High-severity wildfire effects on carbon stocks and emissions in fuels treated and untreated forest. Forest Ecol. Nunamaker, C. Wildfire and Fuels Management. Oles, K. Riparian meadow response to modern conservation grazing management.
Ortega, M. Paphitis, N. Greece: poor response, planning blamed for wildfire deaths. AP News. Pathak, T. Climate change trends and impacts on California agriculture: a detailed review. Agronomy Pausas, J. Fire regime changes in the Western Mediterranean Basin: from fuel-limited to drought-driven fire regime. Change , — Polis, C. Drought and historical rainfall in California.
Powell, J. Powers, S. The Northern California Indians. Overland Monthly and Out West Magazine 9, — Prunicki, M. Air pollution exposure is linked with methylation of immunoregulatory genes, altered immune cell profiles, and increased blood pressure in children. Pyne, S. Quinn-Davison, L. Grasslands Summer, 16— Radeloff, V. Rapid growth of the US wildland-urban interface raises wildfire risk. Rao, D. Reid, C. Critical review of health impacts of wildfire smoke exposure.
Richards, L. Russell, W. Landscape scale vegetation-type conversion and fire hazard in the San Francisco Bay Area open spaces. Safford, H. Saitua, I. Sampson, A. California Range Brushlands and Browse Plants. Sayre, N. Lave, C.
Biermann, and S. Schama, S. Landscape and Memory. Toronto, CA: Vintage Canada. Seastedt, T. Management of novel ecosystems: are novel approaches required? Sidahmed, A. Assessment of goat grazing in chaparral. Nutritive value of chaparral for goats grazing in fuel-breaks. Sikkink, P. Field guide for identifying fuel loading models. Skinner, C.
Assessments and Scientific Basis for Management Options. Wildland Resources Center Report No. Forest Service , — Sommer, L. Spiegal, S. Mooney and E. Starrs, C. The impact of land ownership, firefighting, and reserve status on fire probability in California. Stewart, J. Effects of postfire climate and seed availability on postfire conifer regeneration. Sudworth, G. B, and Gannett, H. Government Printing Office. Syifa, M. Mapping of post-wildfire burned area using a hybrid algorithm and satellite data: the case of the Camp Fire wildfire in California, USA.
Remote Sens. Tarrega, R. Abandonment and management in Spanish dehesa systems: effects on soil features and plant species richness and composition. Taylor, A. Artic Alpine Res. Tosca, M. Turco, M. Climate drivers of the devastating fires in Portugal. Fire Effects Database. University of California Cooperative Extension 1 Reducing Forest Fuels: Grazing. University of California Cooperative Extension 2 Grazing for Fire Prevention. WeedCut Tool.
Many counties and cities in the region have ordinances limiting oak pruning and removal so be sure to check with your local fire agency before trimming or removing oaks. At the lower parts of the range, dominant trees include big-cone Douglas fir and Coulter pine as well as canyon live oak and California bay. On higher slopes, lodgepole, limber, ponderosa, Jeffrey, and sugar pines occur along with white fir, incense cedar, western juniper, and black and canyon oaks.
The low elevation species are sensitive to fire, and thus only found on rocky areas where the geology itself is fire-resistant. In recent years, drought combined with beetle and disease infestations have increased the number of dead trees, and thereby the fire risk in montane forests in this region. Most of the montane forest in southern California occurs in National Forests and a few isolated high elevation communities like Wrightwood, Big Bear, Idyllwild, and Julian.
Residents in these areas should contact CalFire and their local forestry and fire experts and refer to the UC Forest Stewardship site. These vegetation types occur in open canopy stands with sparse undergrowth. Because of the natural separation of the vegetation, these communities do not carry fire well, and have long fire return intervals.
In recent years, however, non-native annual grasses have invaded these communities — creating a continuous dry fuel load. Hence, the frequency of fire in these desert areas has drastically increased. In the year after a fire, these disturbance adapted grasses may be the first plants to germinate, competing with the native vegetation, and slowly converting the natural habitat to more flammable grasslands. Riparian forests are the willows, sycamores, cottonwoods, alders, coast live oaks, and other trees and plants that occur along streams in southern California.
Depending on the steepness of the topography, riparian forests can occur in narrow canyons or along broad, wooded corridors. Historically, these wet areas acted as fire breaks during wildfires.
The greatest impacts occurred after a fire, when flows of sediment down the stream from eroding slopes could wipe out banks, then establish new ones. In recent years, however, many of our riparian forests have been invaded by exotic species. Two of these, Arundo also known as giant cane and Tamarisk also known as salt cedar , grow in dense stands. In summer when water levels recede they may dry out and become dormant turning into potential fuel for fires.
This can change these natural fire breaks into flaming corridors, rapidly fueling the spread of a fire. Giant reed and salt cedar both recover very quickly after a fire, much faster than the native trees, and expand their range along the river or creek. Fire and Climate Change in Southern California. Global warming has occurred rapidly over the past half-century. In the arid U. Southwest, this will mean that future droughts will likely be more severe, and it will mean a change in the timing and type of precipitation.
In California, less precipitation will occur as snow, meaning that less water can be stored in the snow-pack, and that dry summers could see even less water availability. Summertime peak temperatures will increase in many places. The oldest writings on California chaparral followed European disparagement of the scrublands, giving way to a more empirically-grounded view as early as the s. Much attention began to focus on adjusting the climax vegetation concept to accommodate the kind of seral mosaic landscape produced by this vegetation that adapts to and exploits fire disturbances associated with the summer drought climate.
An entire school of thought grew up around the reconceptualization of chaparral as pyrogenic, not just adapted to fire but actually dependent on it and capable of producing the conditions that enable fire. Examples of writings in this vein include: Hanes , for example, concludes: Chaparral fires are both natural and inevitable. A fire-exclusion policy does not prevent fire, it only forestalls fire.
In chaparral stands where fire has been excluded for decades, the threat of fire is greatest. It is possible that, in terms of preserving the chamise-chaparral of southern California, long-term fire exclusion might be the least desirable practice.
Minnich made perhaps the most forceful statement of the fire-dependency of chaparral: Stands as old as 20 years contain little dead fuel and are thus relatively nonflammable Stands older than 30 years show signs of stagnation owing to diminished nutrient cycling Chaparral therefore becomes especially flammable after 30 to 50 years, depending on climate and local fuel accumulation rates p.
The present regime of large, intense conflagrations in southern California chaparral appears to be an artifact of fire suppression. The great achievement of suppression is the extinguishing of small fires Thus prevention efforts by a few forest rangers and settlers between and may have interrupted burning enough to erase some of the presuppression mosaic. Since , small fires have been replaced by ever-larger ones, with numerous conflagrations since the s despite increased suppression investment.
Indeed, the present mosaic in southern California is capable of supporting even more enormous fires, possibly as large as , ha In my own California Geographer article, "Home with a view: Chaparral fire hazard and the social geographies of risk and vulnerability, I expressed this line of thought as: The steady accumulation of fuel is the mechanism by which chaparral creates a condition on which it depends. As a result of this accumulation, the longer the period since a fire, the greater both the probability and the magnitude of the next fire.
This view has recently been challenged. A number of studies have directly questioned whether fire hazard in chaparral is dependent on the age of the stands and whether large fires have, in fact, actually increased in frequency in the wake of fire suppression. Keeley and Fotheringham laid out the case in their Conservation Biology article of , "Historic fire regime in Southern California shrublands" p.
The contemporary fire regime in southern California shrublands mirrors the natural fire regime much more closely than is generally credited. As is the case today, the natural fire regime was likely characterized by many small fires and a few large fires that consumed the bulk of the landscape.
The primary change in the fire regime has been the marked increase in fire frequency in areas of high population density such as southern and central coastal California. Today, fire suppression is required just to maintain some semblance of the natural fire regime. Moritz argues that age-dependency is almost completely trumped by meteorological conditions in accounting for the spatial distribution of fires in chaparral. In his Ecology article, "Spatiotemporal analysis of controls on shrubland fire regimes: Age dependency and fire hazard," Moritz writes: Large fires in chaparral-dominated shrublands of southern and central California are widely attributed to decades of fire suppression.
Prehistoric shrubland landscapes are hypothesized to have exhibited fine-grained age-patch mosaics in which fire spread was limited by the age and spatial pattern of fuels. In contrast, I hypothesize that fires during extreme weather conditions have been capable of burning through all age classes of the vegetation mosaic. Exposure to extreme fire weather therefore appears to override the sensitivity of a fire regime to fuels characteristics at the landscape scale.
Findings contradict the assertion that, in the absence of fire suppression, large fires would be constrained by more complex age-patch mosaics on the landscape. No matter the vehemence of this debate over the relative importance of fuel accumulation and weather conditions in setting the stage for the kind of massive fires seen in California in , both camps do converge on a common implication for wildfire hazard prevention and mitigation.
That is, whether wildfire magnitude and probability increase through time since a previous fire or whether massive landscape-clearing fires are the outcome of a random convergence of extremely dry conditions coupled with anthropogenic or lightning-induced fires, continued residential development of the wildfire- urban interface is hazardous.
It also entails a massive social subsidy: The firefighting taxes and insurance assigned risk pools represent the socialization of household-level risk assumption. As Rodrigue puts it: Consideration of chaparral fire hazard in the Santa Monica Mountains suggests that the benefits of an amenity view are privatized, while the private hazard costs to the household are reduced by the socialization of fire hazard mitigations. Household benefits seem higher than household costs, thus encouraging action on environmentally dysfunctional landscape values if households have the resources to act on them.
The irony of this socialization of vulnerability to chaparral wildfire hazard is that home survival is quite possible even in the most fire-susceptible landscapes.
As Cohen and Saveland put it in a Fire Management Notes article, "Structure ignition assessment can help reduce fire damages in the W-UI": SIAM assesses the potential for structure ignitions from wildfires burning in vegetation and other structures. SIAM is based on the premise that structure survival is the essence of the W-UI fire problem, but structure ignition is the critical element for survival.
Thus, the model specifically addresses the potential for structure ignition rather than the potential for structure survival p. Additionally, experiments and model results indicate that flames are an ignition threat only at close distances to a structure. This finding suggests that nearby landscape vegetation and neighboring structures are important factors in structure ignitions.
However, structures commonly ignite when fires are at distances too great for flame-heated ignitions, suggesting that firebrands are an extremely important source of ignition on and adjacent to a structure.
Vegetation management beyond the structure's immediate vicinity has little effect on structure ignitions p. Conclusion: Toward Reconciliation? There are conceptually a few lines of potential reconciliation between the European and the American traditions in their representations of the Mediterranean scrublands and the rtle of fire in them.
First, the European tradition needs to resituate Medterranean scrub as a natural formation as validly present in the Mediterranean borderlands as woodland and forest but adapted to dominate different specific situations: areas of steep slope, unstable soil, and recurrent fire. Deforestation and overgrazing resulted in accelerated erosion and that increased the areas of steep and unstable slope suitable for expansion of the natural scrublands. Third, European scholars and many others need to reframe what exactly is "natural.
In the Mediterranean borderlands, agriculture and animal husbandry and their transformations of the landscape go back 10, to 11, BP. It is hopeless romanticism to hearken back to a pristine nature in the Mediterranean borderlands and possibly in California as well, given human settlement here sometime after 15, BP.
Fourth, agriculture and animal husbandry may well have produced the kind of mosaicking in the Mediterranean landscape that really could prevent or reduce massive conflagration by reducing the ground cover, particularly the highly flammable ground covers of maquis, garrigue, and grassland. The rural depopulation and abandonment of agropastoralism in the European Mediterranean has ironically been accompanied by an increase in landscape-consuming fires.
The goats might not have been so bad, after all! This counterintuitive effect might be explicable in terms of Cohen's findings about fire behavior and ignition potential. The low cover of crop plants and fodder deny wildfire ladders into the crown through prevention of brand-formation and amplified temperatures. Fifth, California researchers need to settle the balance between fuel accumulation, stand age, meteorologic effects, and ignition sources to understand wildfire dynamics in California chaparral, coastal sage, and grassland.
Sixth, no matter how the California "Fire Wars" work out, the message for urban planning in the Wildland-Urban Interface is clear: Discourage residential development in the W-UI and reprivatize vulnerability to the household level to encourage firewise home modification to promote structural survival in the worst California firestorms.
References Barboni, D. Relationships between plant traits and climate in the Mediterranean region: A pollen data analysis. Journal of Vegetation Science Cohen, Jack, and Saveland, Jim.
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