The Salt Cedar and Russian Olive Control Demonstration Act of 2006 (Public Law 109-320; hereafter the Act) directs the Department of the Interior to submit a report to Congress1 that includes an assessment of several issues surrounding these two nonnative trees, now dominant components of the vegetation along many rivers in the Western United States. Specifically, the Act calls for “…an assessment of the extent of salt cedar and Russian olive infestation on public and private land in the western United States,” which shall

“A) consider existing research on methods to control salt cedar and Russian olive trees; B) consider the feasibility of reducing water consumption by salt cedar and Russian olive trees; C) consider methods of and challenges associated with the revegetation or restoration of infested land; and D) estimate the costs of destruction of salt cedar and Russian olive trees, related biomass removal, and revegetation or restoration and maintenance of the infested land.”
Finally, the Act calls for discussion of

“(i) long-term management and funding strategies…that could be implemented by Federal, State, tribal, and private land managers and owners to address the infestation by salt cedar and Russian olive; (ii) any deficiencies in the assessment or areas for additional study; and (iii) any field demonstrations that would be useful in the effort to control salt cedar and Russian olive.”

The primary intent of this report is to provide the science assessment called for under the Act. A secondary purpose is to provide a common background for applicants for prospective demonstration projects, should funds be appropriated for this second phase of the Act. In addition to relying on the direction provided under Section C of the Act, the authors of this report also drew upon the detailed list of considerations presented in Section E of the Act to guide development of more expansive discussions of topics relevant to saltcedar and Russian olive control efforts.

In addition to the legislative context described above, this chapter describes the geographic and environmental contexts surrounding the Act, including key terminology used in subsequent chapters of this report. Subsequent chapters synthesize the state-of-the-science on the following topics: distribution and abundance (extent) of saltcedar and Russian olive in the Western United States, potential for water savings associated with control of saltcedar and Russian olive and associated restoration, considerations related to wildlife use of saltcedar and Russian olive habitat or restored habitats, methods to control saltcedar and Russian olive, possible utilization of dead biomass following control, and approaches and challenges associated with revegetation or restoration following control. A concluding chapter includes discussion of possible long-term management strategies, areas for additional study, potentially useful field demonstrations, and a planning process for on-the-ground projects involving removal of saltcedar and Russian olive.