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FIRE REGIME CHANGES
USU Extension IVC Presentation, November 27, 2012

Natural Resources/Agriculture Agent, Utah State University Extension, P.O. Box 69, Cedar City, Utah 84721, [email protected]

There has been much debate concerning pre-European settlement conditions of the Western U.S. with many diverse opinions being put forth; however hard data on long-term vegetation changes are scarce to nonexistent for Western landscapes. Historic photos are one source of valuable information documenting past vegetation composition. Repeat photography allows evaluation of these changes and the impact of past land use and management practices. To date, over 2000 photosets have been repeated in southern Utah and placed on the Utah State University Extension web site
(http://www.ext.usu.edu/rra). By systematically evaluating vegetation changes in these photos some clear trends emerge; range conditions have improved, soil erosion has decreased and riparian and stream conditions have improved, while conifers, Pinyon-juniper woodlands and sagebrush have greatly increased in area and density. Evaluation of these photos shows a clear trend of herbaceous vegetation being replaced by woody species. Early settler and explorer accounts document extensive native burning in these systems that has been absent since the turn of the century. This change in fire regimes has resulted in drastic changes in the structure and function of these systems. These photos and history can be used to educate land management agencies and the public about past and present conditions. In addition, this information can be used to outline management actions that will return sustainability to these landscapes.