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Evaluating the Effectiveness of Postfire Rehabilitation Treatments Peter R. Robichaud Jan L. Beyers Daniel G. Neary Introduction Recent large, high severity fires coupled with aub- aequent major hydrological events have generated renewed interest in the linkage between fire and onaite and downstream effects. Fire is a natural and important disturbance mechanism in many ecosys- tems. However, the intentional human auppresaion of foes in the Western United States, beginning in the early 1900'x, has altered natural fire regimes in many areas (Agee 1993). Fire auppresaion can allow fuel loading and forest floor material to increase, resulting in fires of greater intensity and extent than might have occurred otherwise (Norris 1990), High severity fires are of particular concern because they can affect soil productivity, waterahedresponae, and downstream sedimentation, causing threats to human life and property. Duringsevere fire seasons, the USDA Forest Service and other land management agencies spend millions of dollars on poatfire emergency watershed rehabilitation measures intended to minimize flood runoff, onaite erosion, and offsite sedimentation and hydrologic damage. Increased erosion and flooding are certainly the moat visible and dramatic impacts of fire apart from the consumption of vegetation. USDA Forest Service Burn Area Emergency Rehabilitation (BAER) History The first formal reports on emergency watershed rehabilitation after wildfuea were prepared in the 1960's and early 1970'x, although poatfire seeding with greases and other herbaceous species was con- ducted in manyareas inthe 1930's,1940's and 1950's (Christ 1934, Gleason 1947). Contour furrowing and trenching were used when flood control was a major concern (DeByle 1970b, Noble 1965). No formal emer- gency rehabilitation program existed, and funds for watershed rehabilitation were obtained from fire auppresaion accounts, emergency flood control pro- grams, or appropriated watershed restoration ac- counts. In response to a Congressional inquiry on fiscal accountability, in 1974 a formal authority for poatfire rehabilitation activities was provided in the Interior and Related Agencies appropriation. This BAER authority integrated the evaluation of fire severity, funding request procedures, and treatment options. The occurrence ofmanylargefires in California and southern Oregon in 1987 caused expenditures for BAERtreatmenta to exceed the annual BAER authori- zation of $2 million. On several occasions inappropriate requests were made for nonemergency items, and clari- fications were issued that defined real emergency situations warrantingrehabilitation treatments. Poli- cieawere incorporated into the Forest Service Manual (FSM 2523) and the BAER Handbook (FSH 2509.13) that required an immediate assessment of site conditions following wildfire and, where necessary, implementation of emergency rehabilitation mea- sures to: (1) minimize the threat to life and property onaite or offsite; (2) reduce the loss of Boil and onaite productivity;(3)reducethelosxofcontrolofwater;and (4) reduce deterioration of water quality. A concerted effort was made to train BAER team leaders, and regional and national BAER training programs be- came more frequent. At the same time, debates arose overtheeffectiveneasofgraseseedinganditanegative impacts on natural regeneration. Seeding was still the moat widely used treatment, though often applied in conjunction with other hillslope treatments, such as contour-felledlogs, and channel treatments, including straw bale check dame. National Forest apecialiste were encouraged to do implementation monitoring of treatment establishment, ae well as some form of effectiveness monitoring of treatment performance, using regular watershed appropriation funds. In the mid 1990'x, a major effort was undertaken to revise and update the BAER handbook, A steering committee, consisting of regional BAER coordinators and other apecialiate, organized and developed the bulk of the handbook used today. The issue of using native species for emergency revegetation emerged ae a major topic, and the increased use of contour-felled loge caused rehabilitation expenditures to escalate. During the busy 1996 fire season, for example, the Forest Service xpent $11 million on BAER projects. Improvements in the BAER program in the late 1990's included increased BAER training and funding review. Increased needs were identified for BAER USDA Forest Servirs Gen. Tech. Rep. RMRS-GTR-63.2000