Chaparral Fires: Naturally Large, Intense, Infrequent
Large wildfires are a natural and inevitable part of the California landscape
One of the more indefensible claims of the fire mosaic hypothesis is that large fires never existed in southern California prior to the influence of fire suppression activities (usually identified as starting after 1910) because "mixed-aged mosaics" would naturally prevent the spread of fire. The historical record is clear in refuting this claim. Large fires have been a part of the southern California landscape for thousands of years.
A complete analysis of why the Baja Fire Mosaic Hypothesis has been rejected by the scientific community can be download here:
The Problems With Claiming Baja California Doesn't Experience Huge Wildfires Like California
1. There are big wildfires in Baja California.
Raging wildfires in Baja California have left four people dead, destroyed some 200 houses and burned over 7,000 hectares of meadow land.
The state government declared a state of emergency in Tecate, Playas de Rosarito and Ensenada and put Tijuana on pre-alert as a result of the deadly fires.
The Defense Secretariat (Sedena) has implemented the DNIII-E natural disaster emergency response plan and evacuated 1,645 people.
The fires began on Thursday and grew out of control as a result of the Santa Ana winds, which have been reaching speeds as high as 95 kilometers per hour. They have completely burned at least 70 houses in Tecate, 50 in Tijuana and over 30 in Rosarito.
“The most serious fire is the one in Tecate, in which preliminary reports state that 70 houses have been destroyed,” said state Civil Protection director Antonio Rosquillas on Friday. “Unfortunately, two people there have died, two were wounded, and around 60 families affected.”
About 50 fires have been reported in four municipalities.
In Playas de Rosarito, where around 30 houses were completely burned, firefighters found a man and his dog burned to death in the bathroom of a house that was consumed by the flames.
Classes at public schools and universities in the affected cities were canceled on Friday, and police closed highways in the area that were covered in a thick layer of smoke.
Tijuana Mayor Arturo González Cruz believes the fires to have been started by a trash fire at an illegal dump site that grew out of control with the winds.
The federal Secretariat of Security and Citizens Protection (SSPC) reported Friday night that the National Forestry Commission (Conafor) had contained only 35% of the estimated 50 fires. It is not known how much of the region’s natural protected areas have been burned.
2. The age and density of chaparral has little to do with the occurrence of large wildfires.
Proponents of backcountry vegetation treatments and the Baja Fire Mosaic Hypothesis have maintained that the cause of large wildfires is unnatural “fuel” build up due to past fire suppression efforts. It is claimed that younger fuels will not carry a fire. The loss of homes and the burning of young vegetation by the Silver Fire contradict this notion.
3. Huge, wind-driven wildfires have always occured in California.
4. Fire suppression has not not been effective in excluding fire from southern California chaparral AND has not resulted in unnatural amounts of vegetation.
The Research Refuting the Baja Fire Mosaic Hypothesis
Another paper concluded,
"Despite overwhelming evidence that fire frequency is continuing to increase in coastal southern California (Keeley et al. 1999, Moritz et al. 2004, NPS 2004), the current fire-management program subscribes to the paradigm that fire suppression has led to fewer, larger fires, and that landscape-scale prescribed fire should be used to create a fine-scaled age mosaic. Considering the results of our simulations, we believe that adding more fire to the landscape through broad-scale prescribed burning may have negative ecological effects. Instead, our results are consistent with recent recommendations from the U.S. National Park Service to change the fire management program to focus fuel-reduction efforts and prescribed fire on strategic locations such as the wildland–urban interface (NPS 2004)."From:Syphard A.D., Franklin J., Keeley J.E. 2006. Simulating the effects of frequent fire on southern California coastal shrublands. Ecological Applications 16: 1744-1756.
The Primary Papers
Mensing, S.A., Michaelsen, J., Byrne, R. 1999. A 560 year record of Santa Ana fires reconstructed from charcoal deposited in the Santa Barbara Basin, California. Quaternary Research. Vol. 51:295-305.
Zedler, P.H., Seiger, L.A. 2000. Age Mosaics and Fire Size in Chaparral: A Simulation Study. In 2nd Interface Between Ecology and Land Development in California. USGS Open-File Report 00-02, pp. 9-18.
Discussion of the Fire Mosaic Hypothesis in Conservation BiologyKeeley, J.E. and C.J. Fotheringham. 2001. Historical Fire Regimes in Southern California Shrublands (analysis of Minnich's hypothesis).
Minnich, R. 2001. An integrated model of 2 fire regimes (response to Keeley/Fotheringham 2001).
Keeley J.E. and C.J. Fotheringham. 2001. History and Management of crown-fire ecosystems: a summary and response (Response to Minnich above).
Papers Examining and Rejecting the Fire Mosaic HypothesisMoritz, M.A., J.E. Keeley, E.A. Johnson, and A.A. Schaffner. 2004. Testing a basic assumption of shrubland fire management: Does the hazard of burning increase with the age of fuels? Frontiers in Ecology and the Environment. 2:67-72.
Keeley, J.E. and P.H. Zedler. 2009. Large, high-intensity fire events in southern California shrublands: debunking the fine-grain age patch model. Ecological Applications 19: 69-94.
...Appendix A to above paper.
...USGS Publication Brief on above paper.
Lombardo, K.J., T.W. Swetnam, C.H. Baisan, M.I. Borchert. 2009. Using bigcone Douglas-fir fire scars and tree rings to reconstruct interior chaparral fire history. Fire Ecology 5: 32-53. Other Important PapersMoritz, M. A. 2003. Spatiotemporal analysis of controls on shrubland fire regimes: age dependency and fire hazard. Ecology 84:351-361.
Keeley, J.E. 2002. Fire management of California shrubland landscapes. Environmental Management 29: 395-408.
Keeley, J.E. 1982. Distribution of lightning and man-caused wildfires in California, pp. 431-437. In C.E. Conrad and W.C. Oechel (eds), Proceedings of the International Symposium on the Dynamics and Management of Mediterranean Type Ecosystems. USDA Forest Service, General Technical Report PSW-58.
Halsey, R.W., J.E. Keeley, K. Wilson. 2009. Fuel age and fire spread in southern California chaparral ecosystems: natural conditions vs. opportunities for fire suppression. Fire Management Today 69, #2: 22-28. In terms of creating mosaics to increase biodiversity, researchers from another Mediterranean-type climate, Australia concluded, "We identified serious shortcomings of PMB (patch mosaic burning): the ecological significance of different burning patterns remains unknown and details of desired fire mosaics remain unspecified. This has led to fire-management plans based on pyrodiversity rhetoric that lacks substance in terms of operational guidelines and capacity for meaningful evaluation. We also suggest that not all fire patterns are ecologically meaningful: this seems particularly true for the highly fire-prone savannas of Australia and South Africa. We argue that biodiversity-needs-pyrodiversity advocacy needs to be replaced with a more critical consideration of the levels of pyrodiversity needed for biodiversity and greater attention to operational guidelines for its implementation."From Parr, C.L. and A.N. Andersen. 2006. Patch mosaic burning for biodiversity conservation: a critique of the pyrodiversity paradigm. Conservation Biology 20: 1610-1619. Lastly, here are two classic papers discussing the importance of examining all variables and not ignoring contrary dataChamberlin, T.C. 1890. The method of multiple working hypotheses. Science: Feb. 7. Also reprinted in 1965. Science 148: 754 –759.
Feynman, R.P. 1974. Cargo cult science. Engineering and Science, June.