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8 I Riparian Ecosystem Recovery United States (Anderson et al. 1978). Other recovery strategies include improv- ing livestock management, installing stream bank stabilizing structures, and performing upland treatments. These strategies have been implemented either alone or in combination, with varying degrees of success. In addition, legisla- tion designed to protect riparian ecosystems by maintaining minimum stream- flows has been developed during recent years and may playa major role in protecting riparian ecosystems in the years to come (Arizona Rivers Coalition 1991). Riparian revegetation uses all types of propagules, including cuttings, poles, seedlings, and seeds. When used effectively, revegetation can produce dramatic results, helping to replace lost riparian vegetation and stabilize dete- riorating conditions, thereby initiating recovery of the riparian ecosystem. For example, establishing woody vegetation along stream banks can expedite the recovery of damaged riparian areas by slowing or preventing stream bank ero- sion, which provides greater opportunities for other vegetation (e.g., grasses, sedges, forbs, and rushes) to establish (Porter and Silberberger 1961; Miller and Borland 1963; Maddock 1976). One of the most critical lessons learned from the experiences of past ripar- ian recovery efforts, as well as from recovery efforts that focused on other ecosystems, is the importance of evaluating site conditions to understand cur- rent conditions, the extent to which they have declined, and the reasons for their decline (Van Haveren and Jackson 1986; Carothers et al. 1990; Briggs et al. 1994). In general, we are often guilty of jumping to conclusions about the causes of degradation, how we are going to address the causes, and what the end point should be. Only by evaluating site conditions can the information required to develop a realistic and effective recovery plan be collected. Underscoring this point are the results of a study that evaluated a group of riparian revegetation projects in Arizona (Briggs 1992). This study found that incorporating recovery techniques (in addition to, or in lieu of, revegetation) such as bank stabilization structures, check dams (fig. 1.2), irrigation, and improved land management strategies that address the causes of site decline (either indirectly or directly) was a commonality of the majority of the projects that achieved their objectives. In brief, the ability of these other recovery strategies to overcome the causes of site degradation appears to have a more significant impact on the overall results of the projects than does revegetation. Designing and implementing recovery strategies that address the causes of site decline, of course, requires that the causes of site decline be understood. These results also illustrate why riparian revegetation often produces only marginal results - when revegetation is used alone, the factors responsible for the ini-