By Janelle Winters, NMNH Department of Botany intern
While using J.W. Toumey’s field book to chronicle the botanical impacts of cattle ranching in the turn-of-the twentieth century Tonto Basin (see Toumey and the Tonto Basin), a question percolated in my mind. What happened in the Tonto since Toumey described its ecological devastation in 1892? Toumey’s field book and correspondence became a launching point for primary and secondary research into the long term impacts of ranching on botanical diversity.
Recall from our earlier post that Toumey had left the Tonto in August of 1892, during the beginning of a long drought that would claim the lives of the majority of the cattle. After these massive die-offs, the federal government intervened. In 1898 President William McKinley began to reserve Basin lands, and President Theodore Roosevelt established the Tonto National Forest in 1905.
Gifford Pinchot – who would later become the first Chief of the Forest Service and a Pennsylvania Governor – visited the Tonto at the turn of the century. He set the stage for what would be a tepid stance on regulating cattle grazing in the west. According to modern scholar Adam Sowards, Pinchot’s effort to “please all Arizona interests – the farmers, the timber industry, and the ranchers” led him to declare that overgrazing – but not grazing itself – was damaging in forest ranges. The crux was that nobody determined what constituted overgrazing. So, cattle and sheep numbers in the Tonto continued to exceed carrying capacity of the land, and nonnative grasses and shrubs continued to replace native grasses.
Sowards explains that, later, when “Forest service policy reflected patriotism, not ecology” by allowing blatant overstocking to supply beef to WWI troops, this was “the final straw for the range.” It was shortly later that Senior Forest Ranger Fred Croxen declared in a 1926 public speech that,
“White man, the most destructive of animals, brought his herds to a virgin range only fifty short years ago, and abused it in every way he could. We see the result today. Much of it is worthless, ruined beyond recovery, some will come back… but…all the oldtimers I talked with are very glad government supervision came at last, but it came too late -- let us do our part to save and improve what is left.”
Renowned ecologist Aldo Leopold, who was responsible for inspecting the Tonto National Forest in 1923, echoed this statement. He wrote simply that, “When the cattle came the grass went, fires diminished, and erosion began… they grazed it to death” (Leopold 1924).
Cattle ranching in the Tonto continues today, albeit on a smaller scale. The Taylor Grazing Act of 1934 officially ended the “open range” in the Tonto and throughout the West (Sowards 1998), but a number of the same homesteaders from the 1870s continue to operate the land (U.S. Forest Service). Many areas of the Tonto and other southern Arizona ranges still have grasslands reduced to dirt, streams eroded to arroyos, and invasive shrubs unchecked by fires (Sayre 1999).
A quick lesson in the ecological effects of ranching is helpful in understanding this prolonged devastation. Conservation biologists explain that overgrazing reduces dense grass root systems, which fosters erosion and lowers the water table. Lowered water tables prevent the roots of plants, like cottonwood, willows, and mesquite, from reaching the water necessary for survival (Witzeman 2002, Fleischner 1994, Leopold 1924).
This has allowed exotic grasses and more woody plants to establish themselves in southern Arizona – just like Toumey and Leopold observed. As of 1996, lack of native grassland vegetation had been implicated in the fates of 70 of 116 animal species listed as threatened in the state of Arizona (Arizona State Game and Fish Department 1996, Witzeman 2002). Some public interest groups are currently campaigning to allow controlled fires – similar to those of the Apaches – in the Arizona borderlands (Gottfried 2009). They hope to restore the ecological balance that has eluded the Tonto region since settlers arrived with their cattle nearly a century and a half ago.
References:
1. Toumey, J.W. Journal, Catalogs 1-809 Arizona (S.I. Library, 1892)
2. Toumey, J.W. Correspondence to George Vasey (S.I. Archives, 1891-1892)
3. Sowards A.M., “Reclamation, Ranching, and Reservation: Environmental, Cultural, and Governmental Rivalries in Transitional Arizona,” Journal of the Southwest Autumn 1998 40(3): 333-361.
4. Croxen F.W., “History of Grazing on Tonto” Tonto Grazing Conference (Phoenix, Arizona) Nov. 4-5, 1926
5. Leopold, A. “Forest Service Records: Inspection Records” Tonto National Forest 1923, 480-556. (University of Wisconsin Libraries)
6. Leopold A, “Grass, brush, timber, and fire in Southern Arizona,” Journal of Forestry 1924 22: 1-10.
7. Southwestern Regional Office files in Albuquerque, United States Federal Forest Service, Tonto NF Historical Photographs <http://www.fs.fed.us/r3/about/history/ton/index.htm>
8. United States Department of Agriculture Forest Service, Tonto National Forest Overview (History) <http://www.fs.usda.gov>
9. Sayre N., “The Cattle Boom in Southern Arizona: Towards a Critical Political Ecology,” Journal of the Southwest Summer 1999 41(2): 239-71.
10. Witzeman B, “An educational tool about cattle grazing” The Cactus Wren-dition (Newsletter of the Maricopa Audobon Society) Spring 2002 www.rangenet.org/directory/witzeman/tool/
11. Fleischner T.L., “Costs of Livestock Grazing in Western North America,” Conservation Biology Sept. 1994 8(3): 629-644.
12. Arizona Game and Fish Department, “Wildlife of Special Concern in Arizona,” March 16 1996 < http://www.azgfd.gov/pdfs/w_c/heritage/heritage_special_concern.pdf>
13. Gottfried G.J., Allen L.S., Warren P.L., McDonald B., Bemis R.J., Edminster C.B., “Private-Public collaboration to reintroduce fire into the changing ecosystems of the southwestern borderlands region” Fire Ecology Special Issue 2009 5(1): 85-99.
Very interesting subject, regards for posting.
Posted by: apolonia | Sunday, 27 January 2013 at 11:52 AM