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i WATERSHED RESTORATION Further Degraded Dynamic State(s) Na[Ural Degrading land use activities ';cos stem Degraded Ecosystem Potential State Natural ~ Ecosystem ~ Passive Restoration Successful Restoration Active Restoration ;1lisinterpretalion of New Ecosystem Ecosystem Needs Equilibrium Failure major dam), the natural regeneration of riparian-obligate trees and other woody species may be severely limited (Bradley and Smith 1986; Rood and Mahoney 1990). With- out arecovery of high-flow regimes, artificial revegetation will likely be necessary to perpetuate forests within the historic floodplains. Gallery forests can be naturally per- petuated only if flow management allows high-water events to create conditions for regeneration. By definition, ecological restoration of riparian vegeta- tion entails the planting of only native species. The ttse of exotic plant species to "improve" riparian habitats associ- ated with native fisheries is tantamount to introducing brook trout (Salz~elinus folttirtnlis) or some other exotic fish as a substitute for extirpated native bull trout (Snlztelinus confluentus) populations. In addition, revegetation with native species should focus on those areas of the riparian zone that contain appropriate substrates and micro- dimates. The planting of willows or conifers in native sedge meadows will likely result in failure or the creation of an unnatural, unsustainable plant community. In addition to revegetation, a suite of sihricultural op- tions to accelerate riparian forest development can be implemented. Creation of small canopy gaps, small clear- ings, and placement of coarse wood debris on the flood- plain to serve as nurse logs can enhance growth rates of existing trees or proride conditions for establishment o: uesira~.ie trees. Oyerstorv manipulations should be done ir, a patchy, irregular manner to mimic natural dishirbances and forest structure. In some instances, the products of thinning can be used as a source of instream wood or nurse logs. Prescribed burning also can be an important activity when used to mimic the disturbance regime of natural fires. Appropriate livestock grazing managemenk is of major importance for the proper functioning of many western riparian zones, particularly where grazing is deemed a primary use (e.g., private ranch lands). While some have suggested that livestock can be used as a "tool" in riparian enhancement, there is no ecological basis to indicate that livestock grazing, under any management strategy can accelerate riparian recovery more rapidly than total exclu- sion (Platts 1991; Elmore and Kauffman 1990. The passive 2~ -. Fisheries Figure 3 explores the conceptual pathways or ecosystem response t ecological restoration of western North American riparian and strear ecosystems. restoration approach of livestock exclusion demonstrably has resulted in a rapid recovery of riparian vegetation (U.S. General Accounting Office 1988; Beschta et al. 1991; Kauffman et al. 1993); however, less is known regarding rates of channel morphology recovery (P. McDowell, Uni- versity of Oregon, personal communications). Although moderate levels of winter grazing, late-season (autumn) grazing, or early-season (spring) grazing have been demonstrated to reduce harm by livestock in some ripari- an zones (Platts 1991; Elmore and Kauffman 199-1), any grazing practice must include close monitoring of wood use and bank conditions so that livestock can be promptly removed before significant damage occurs. The variety of approaches to active restoration is potentially large and beyond the scope of this document, but what is important regarding active restoration procedures is that any approaci reestablish the disturbance regimes and conditions so nat- ural hydrologic, geomorphic, and biotic processes can occur. In some cases, active restoration may require removing or altering artificial structures contributing to degradation or preventing natural ecosystem processes from occurring. These practices might include obliteratin, roads that are contributing excessive amounts of seciimen` removing instream or streambank structures (e.~.., rip-ran, ~,abions, and anchored structures) that limit cl,r;nne d~-namics, reconfigurin, channelized reaches to in~rea„' their sinuosity and floodplain connectivity and re:no~'in~_ mainstem darns to eliminate barriers to fish mi`ratior. hrstrearfz Stra~ctures A general deficiency of large, woody debris ~rithin streams draining forested watersheds is common through- out much of the Pacific Northwest, primarily because of historical practices of timber harvesting of riparian forests, splash damming, agricultural conversion, livestock graz- ing, and stream "cleaning" (i.e., the purposeful removal of ~~~ood debris). The natural recruitment of coarse, woody debris in such streams often requires much time (.Gregor and Ashkenas 1990). As a result, managers often add lard', tti•oodv debris. i~Vhere such practices are needed, the pr, mars goal should be to proride natural amottn , t~. p~~. Special issue oe V'/a+ershed P.estoration