International Journal of Wildland Fire International Journal of Wildland Fire Society
Journal of the International Association of Wildland Fire

Fire suppression impacts on postfire recovery of Sierra Nevada chaparral shrublands*

Jon E. Keeley A B E , Anne H. Pfaff A and Hugh D. Safford C D
+ Author Affiliations
- Author Affiliations

A US Geological Survey, Western Ecological Research Center, Sequoia-Kings Canyon Field Station, Three Rivers, CA 93271-9651, USA.

B Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095, USA.

C USDA Forest Service, Pacific Southwest Region, Vallejo, CA 94592, USA.

D Department of Environmental Science and Policy, University of California, Davis, CA 95616, USA.

E Corresponding author. Telephone: +1 559 565 3170; email:

International Journal of Wildland Fire 14(3) 255-265
Submitted: 21 April 2005  Accepted: 19 July 2005   Published: 12 September 2005


A substantial portion of chaparral shrublands in the southern part of California’s Sierra Nevada Mountain Range has never had a recorded fire since record keeping began in 1910. We hypothesised that such long periods without fire are outside the historical range of variability and that when such areas burn, postfire recovery is weaker than in younger stands. We predicted that long fire-free periods will result in loss of shrub species and deterioration of soil seed banks, which, coupled with higher fire intensities from the greater accumulation of dead biomass, will lead to poorer postfire regeneration. The 2002 McNally Fire burned ancient stands that were as much as 150 years old, as well as much younger (mature) stands. Based on shrub skeletons in the burned area as a surrogate for prefire density, we found that ancient stands change in structure, owing primarily to the loss of obligate seeding Ceanothus cuneatus; other species appear to have great longevity. Despite the reduction in C. cuneatus, postfire shrub–seedling recruitment remained strong in these ancient stands, although some seed bank deterioration is suggested by the three-quarters lower seedling recruitment than recorded from mature stands. Total diversity and the abundance of postfire endemic annuals are two other response variables that suggest that these ancient stands are recovering as well as mature stands. The one area of some concern is that non-native species richness and abundance increased in the ancient stands, suggesting that these are more open to alien colonisers. It is concluded that chaparral more than a century old is resilient to such long fire-free periods and fire severity impacts are indistinguishable from those in younger chaparral stands.


Borchert MI, Odion DC (1995) Fire intensity and vegetation recovery in chaparral: a review. In ‘Brushfires in California wildlands: ecology and resource management’. (Eds JE Keeley, T Scott) pp. 91–100. (International Association of Wildland Fire: Fairfield, WA)

Caprio AC, Graber DM (2000) Returning fire to the mountains: can we successfully restore the ecological role of pre-Euroamerican fire regimes to the Sierra Nevada? In ‘Wilderness science in a time of change conference’. (Eds DN Cole, SF McCool, J O’Loughlin) pp. 233–241. (USDA Forest Service, Rocky Mountain Research Station: Missoula, MO)

Conard SG, Regelbrugge JC (1994) On estimating fuel characteristics in California chaparral. In ‘12th Conference on Fire and Forest Meteorology’. pp. 120–129. (American Meteorology Society: Boston)

Hickman JC (1993) ‘The Jepson manual: higher plants of California.’ (University of California Press: Berkeley, CA)

Johnson EA, Miyanishi K , Bridge SRJ (2001) Wildfire regime in the boreal forest and the suppression–fuel build-up idea. Conservation Biology  15, 1554–1557.
CrossRef |

Jones and Stokes (1987) ‘Sliding toward extinction: the state of California’s natural heritage, 1987.’ (California Nature Conservancy: San Francisco, CA)

Keeley JE (1986) Resilience of Mediterranean shrub communities to fire. In ‘Resilience in Mediterranean-type ecosystems’. (Eds B Dell, AJM Hopkins, BB Lamont) pp. 95–112. (Dr W. Junk: Dordrecht, The Netherlands)

Keeley JE (1992a) Demographic structure of California chaparral in the long-term absence of fire. Journal of Vegetation Science  3, 79–90.

Keeley JE (1992b) Recruitment of seedlings and vegetative sprouts in unburned chaparral. Ecology  73, 1194–1208.

Keeley JE (1993) Utility of growth rings in the age determination of chaparral shrubs. Madrono  40, 1–14.

Keeley JE (2000) Chaparral. In ‘North American terrestrial vegetation’. (Eds MG Barbour, WD Billings) pp. 203–253. (Cambridge University Press: Cambridge)

Keeley JE (2002) Fire management of California shrubland landscapes. Environmental Management  29, 395–408.
CrossRef | PubMed |

Keeley JE (2004) VTM plots as evidence of historical change: goldmine or landmine? Madrono  51, 372–378.

Keeley JE (in press) Fire in the South Coast region. In ‘Fire ecology of California ecosystems’. (Eds J Fites-Kaufman, N Sugihari, J van Wangtendonk) In press. (University of California Press: Los Angeles, CA)

Keeley JE, Davis FW (in press) Chaparral. In ‘Terrestrial vegetation of California’. (Ed. MG Barbour) In press. (University of California Press: Los Angeles, CA)

Keeley JE, Fotheringham CJ (2003a) Impact of past, present, and future fire regimes on North American Mediterranean shrublands. In ‘Fire and climatic change in temperate ecosystems of the western Americas’. (Eds TT Veblen, WL Baker, G Montenegro, TW Swetnam) pp. 218–262. (Springer: New York)

Keeley JE , Fotheringham CJ (2003b) Species area relationships in mediterranean-climate plant communities. Journal of Biogeography  30, 1629–1657.
CrossRef |

Keeley JE , Fotheringham CJ (2005) Plot shape effects on plant species diversity measurements. Journal of Vegetation Science  16, 249–256.

Keeley JE , Keeley SC (1977) Energy allocation patterns of sprouting and non-sprouting species of Arctostaphylos in the California chaparral. American Midland Naturalist  98, 1–10.

Keeley JE, Fotheringham CJ , Morais M (1999) Reexamining fire suppression impacts on brushland fire regimes. Science  284, 1829–1832.
CrossRef | PubMed |

Keeley JE, Lubin D , Fotheringham CJ (2003) Fire and grazing impacts on plant diversity and alien plant invasions in the southern Sierra Nevada. Ecological Applications  13, 1355–1374.

Keeley JE, Fotheringham CJ , Keeley MB (2005) Determinants of postfire recovery and succession in mediterranean-climate shrublands of California. Ecological Applications  15,

McCune B , Keon D (2002) Equations for potential annual direct incident radiation and heat load. Journal of Vegetation Science  13, 603–606.

Minnich RA (1983) Fire mosaics in southern California and northern Baja California. Science  219, 1287–1294.

Moreno JM , Oechel WC (1991) Fire intensity and herbivory effects on postfire resprouting of Adenostoma fasciculatum in southern California chaparral. Oecologia  85, 429–433.
CrossRef |

Moritz MA, Keeley JE, Johnson EA , Schaffner AA (2004) Testing a basic assumption of shrubland fire management: how important is fuel age? Frontiers in Ecology and the Environment  2, 67–72.

NOAA (2004) ‘Climatological data annual summary California.’ (National Oceanographic and Atmospheric Agency: Asheville, NC)

Paysen TE , Cohen JD (1990) Chamise chaparral dead fuel fraction is not reliably predicted by age. Western Journal of Forestry  5, 127–131.

Riggan PJ, Franklin SE, Brass JA, Brooks FE (1994) Perspectives on fire management in mediterranean ecosystems of southern California. In ‘The role of fire in Mediterranean-type ecosystems’. (Eds JM Moreno, WC Oechel) pp. 140–162. (Springer: New York)

Rundel P, Baker GA, Parsons DJ, Stohlgren TJ (1987) Postfire demography of resprouting and seedling establishment by Adenostoma fasciculatum in the California chaparral. In ‘Plant response to stress. Functional analysis in Mediterranean ecosystems’. (Eds Pages JD, Tenhunen, FM Catarino, OL Lange, WC Oechel) pp. 575–596. (Springer: Berlin)

Safford H , Harrison S (2004) Fire effects on plant diversity in serpentine and sandstone chaparral. Ecology  85, 539–548.

Schoennagel T, Waller DM, Turner MG , Romme WH (2004) The effect of fire interval on post-fire understorey communities in Yellowstone National Park. Journal of Vegetation Science  15, 797–806.

Shmida A (1984) Whittaker’s plant diversity sampling method. Israel Journal of Botany  33, 41–46.

Zammit CA , Zedler PH (1988) The influence of dominant shrubs, fire, and time since fire on soil seed banks in mixed chaparral. Vegetatio  75, 175–187.

Zammit CA , Zedler PH (1994) Organisation of the soil seed bank in mixed chaparral. Vegetatio  111, 1–16.

Zedler PH (1995) Fire frequency in southern California shrublands: biological effects and management options. In ‘Brushfires in California wildlands: ecology and resource management’. (Eds JE Keeley, T Scott) pp. 101–112. (International Association of Wildland Fire: Fairfield, WA)

* This manuscript was written and prepared by U.S. Government employees on official time and therefore is in the public domain and not subject to copyright.

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