PROFILE Control of Tamarix in the Western United States: Implications for Water Salvage, Wildlife Use, and Riparian Restoration PATRICK B. SHAFROTH Fort Collins Science Center US Geological Survey Fort Collins, Colorado 80526, USA JAMES R. CLEVERLY Department of Biology University of New Mexico Albuquerque, New Mexico 87131, USA TOM L. DUDLEY Department of Natural Resource and Environmental Science University of Nevada Reno, Nevada 89512, USA JOHN P. TAYLOR Bosque del Apache National Wildlife Refuge US Fish and Wildlife Service Socorro, New Mexico 87801, USA CHARLES VAN RIPER III Southwest Biological Science Center US Geological Survey Tucson, Arizona 85721, USA EDWIN P. WEEKS National Research Program US Geological Survey Denver, Colorado 80225, USA JAMES N. STUART Conservation Services Division New Mexico Department of Game and Fish Santa Fe, New Mexico 87504, USA ABSTRACT / Non-native shrub species in the genus Tamarix (saltcedar, tamarisk) have colonized hundreds of thousands of hectares of floodplains, reservoir margins, and other wetlands in western North America. Many resource manag- ers seek to reduce saltcedar abundance and control its spread to increase the flow of water in streams that might otherwise be lost to evapotranspiration, to restore native riparian (streamside) vegetation, and to improve wildlife habitat. However, increased water yield might not always occur and has been substantially lower than expected in water salvage experiments, the potential for successful revegetationisvariable,andnotallwildlifetaxaclearlyprefer native plant habitats over saltcedar. As a result, there is considerable debate surrounding saltcedar control efforts. We review the literature on saltcedar control, water use, wildlife use, and riparian restoration to provide resource managers, researchers, and policy-makers with a balanced summary of the state of the science. To best ensure that the desired outcomes of removal programs are met, scientists and resource managers should use existing information and methodologies to carefully select and prioritize sites for re- moval, apply the most appropriate and cost-effective control methods, and then rigorously monitor control efficacy, revegetation success, water yield changes, and wildlife use. Invasive species are organisms intentionally or accidentally introduced by human activity to a new region that have spread extensively and rapidly (Richardson and others 2000). Plant invasions cause estimated tens of billions of dollars of economic losses each year in the United States (Pimentel and others 2001) and can impose undesirable alterations to spe- cies, populations, community structure, and ecosystem functions (Mack and others 2000). Saltcedar (tama- risk; Tamarix spp.) is an invasive shrub in the western United States that has been the target of many con- trol and environmental restoration efforts, beginning KEY WORDS: Tamarix; Saltcedar; Tamarisk; Evapotranspiration; Water salvage; Wildlife use; Riparian restoration; Revegetation; Invasive species; Exotic species; Control Published online March 18, 2005. *Author to whom correspondence should be addressed; email: pat_shafroth@usgs.gov Environmental Management Vol. 35, No. 3, pp. 231À246 ª 2005 Springer Science+Business Media, Inc. DOI: 10.1007/s00267-004-0099-5