Number of fire-scar sites (chronologies) in the Southwest recording fire dates in each year, 1700 to 1990, out of a total of 63 sites. The decrease in recorded fires after ca. 1900 reflects livestock grazing affecting fine fuels and subsequent fire suppression policies by government agencies. Source: Swetnam, Thomas W. and J.L. Betancourt, "Mesoscale Ecological Responses to Climatic Variability in the American Southwest" http://geochange.er.usgs.gov/sw/impacts/biology/fires_SOI/ 4/10/03

Before fire suppression became government policy, livestock grazing had already become remarkably effective in reducing the incidence of wildfire. Yet human-caused wildfire still plagued the American Southwest as frontiersmen and tourists alike rarely bothered to prevent a campfire from escaping. Such practices receded in the 20th century as settlers replaced transients and as farmers abandoned the open fire for the confined hearth.

"Your Forests - Your Fault - Your Loss!" Uncle Sam as a forest ranger. c. 1934. Artist: James Montgomery Flagg.

The habits of wandering tourists continued to aggravate professional foresters charged with protecting public lands. Soon visitors were required to carry shovel, ax, and bucket. Failure to comply could bring prosecution under trespass laws, and guilty parties could be made to pay for the costs of suppression. Army troops were even stationed on the forests during the summer "for moral effect."

Locals were similarly admonished to abandon traditional uses of controlled fire for a program of fire exclusion. By World War II, as forest products acquired value as war material, incendiarism was tanatamount to sabotage. The first Smokey Bear poster appeared in 1945.

Even as the campaign for the hearts and minds of the American public was adding new converts, the scientific evidence in favor of fire and prescribed burning began to mount. The dramatic explosion of woody vegetation at the expense of grasslands during a wet cycle in the early part of the 20th century did not go unnoticed. Reseachers like Charles Cooper began to argue for prescribed fire in pine forest and desert grassland.

By the late 1960s fire exclusion seemed as serious a menace to forest health as overgrazing. By the early 1970s more acres were being burned for prescribed fire than were burned from wildfire. Smokey Bear's message has been revamped. His new message, "Only you can prevent wildfires'' - as opposed to "forest fires'' - reflects the rising dangers faced by homeowners living closer than before to areas that are vulnerable to flames.

References

Cooper, Charles F. 1960. Changes in vegetation, structure, and growth of southwestern pine forests since white settlement. Ecological Monographs 30(2): 129-164.

Covington, W. W., Everett, R. L., Steele, R. W., Irwin, L. I., Daer, T. A. and Auclair, A. N. D. 1994. Historical and anticipated changes in forest ecosystems of the inland west of the United States. Journal of Sustainable Forestry 2: 13-63.

Langston, Nancy. 1995. Forest Dreams, Forest Nightmares: The Paradox of Old Growth in the Inland West. University of Washington Press.

Moody, R., Buchanan, L., Melcher, R. and Wistrand, H. 1992. Fire and forest health: Southwestern Region. USDA Forest Service, Southwestern Region, Albuquerque, NM, 39 pp.

Pyne, Stephen J. and W. Cronin. 1982. Fire in America: A cultural history of wildland and rural fire. Princeton, NJ: Princeton University Press.

Stuart, John D. "Effects of Fire Suppression on Ecosystems and Diversity." http://biology.usgs.gov/s+t/SNT/noframe/lu107.htm, in U.S. Geological Survey. 1997. Status and Trends of the Nation's Biological Resources http://biology.usgs.gov/s+t/SNT/ 04/11/03.

Swetnam, Thomas W. and Julio L.Betancourt. 1997. "Mesoscale Ecological Responses to Climatic Variability in the American Southwest." http://geochange.er.usgs.gov/sw/impacts/biology/fires_SOI/ 4/10/03.

J.G.

Last edited June 6, 2003