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sediment. Rotational slumps normally do not move any significant distance. Slumps are only major prob- lems when they occur close to stream channels, but they do expose extensive areas of bare soil on slope surfaces. Debris flows and avalanches are the largest, moat dramatic, and main form of mass wasting that delivers sediment to streams (Benda and Cundy 1990). They can range from slow moving earth flows to rapid avalanches of soil, rock, and woody debris. Debris avalanches occur when the mass of soil material and soil water exceed the sheer strength needed to main- tain the mass in place. Steep slopes, logging, road construction, heavy rainfall, and fires aggravate de- bris avalanching potential. Many fire-associated mass failures are correlated with development ofwater repellency in soils (DeBano and others 1998). Chaparral vegetation in the South- western United States is a high hazard zone because of the tendency to develop water repellent soils. Water repellency also occurs commonly elsewhere in the West after wildfires. Sediment delivery to channels by mass failure can be as much as 50 percent of the total postfire sediment yield. Wildfire in chaparral vegeta- tion in coastal southern California increased debris avalanche sediment delivery from 18 to 4,845 yds mi z yr 1(7 to 1,910 ms km-2 yr 1) (Wells 1981). Cannon (1999) describes two types of debris flow initiation mechanisms, infiltration soil slip and sur- face nmoffafterwildfiresinthe Southwestern United States.Ofthese, aurfacerunoffwhichincreases sedi- ment entrainment was the dominate triggering mechanism. Dry Ravel-Dry ravel is the gravity-induced down- slope surface movement of soil grains, aggregates, and rock material, and is a ubiquitous process in semiarid ateepland ecosystems (Anderson and others 1959). Triggered by animal activity, earthquakes, wind, and perhaps thermal grain expansion, dry ravel may beat be described as a type of dry grain flow (Wells 1981). Fires greatly alter the physical characteristics of hillside slopes, stripping them oftheir protective cover of vegetation and organic litter and removing barriers that were trapping sediment. Consequently, during and immediately following fires, large quantities of surface material are liberated and move downalope as dry ravel (Krammea 1960, Rice 1974). Dry ravel can equal or exceed rainfall-induced hillslope erosion after fire in chaparral ecosystems (Krammea 1960, Wohlgemuth and others 1998). Emergency Watershed Rehabilitation Treatment Effectiveness Early burned area emergency rehabilitation efforts were principally aimed at controlling erosion. Workby Bailey and Copeland (1961), Christ (1934), Copeland USDA Forest Service Gen. Tech. Rep. RMRS-GTR-63. 2000 (1961,1968),Ferrell(1959),Heede(1960,1970),andNoble (1965) demonstrated that various watershed manage- ment techniques could be used on forest, shrub, and grass watersheds to control both storm runoff and erosion. Many of these techniques have been refined, improved, and augmented from other disciplines (ag- riculture, construction) to form the set of BAER treat- ments in use today. With the exception of grass seeding, relatively little has been published specifically on the effectiveness and ecosystem impacts of moat poatfire rehabilitation treatments. We discuss the BAER literature by treat- ment categories: hillslope, channel, and road treat- ments. BAER treatments will be categorized in this manner throughout this report. Hlllslope Treatments-Hillslope treatments in- clude grass seeding, contour-felled loge, mulch, and other methods intended to reduce surface runoff and keep postfire soil in place on the hillslope. These treat- ments are regarded as a first line of defense against postfire sediment movement, preventing subsequent depcaition in unwanted areas. Consequently, more research has been published on hfllslope treatments than on other methods. Broadcast Seeding-The moat common BAER prac- tice is broadcast seeding of grasses, usually from air- craft. Grass seeding after fire for range improvement has been practiced for decades, with the intent to gain useful products from land that will not return to timber production for many years (Christ 1934, McClure 1956). As an emergency treatment, rapid vegetation establishment hoe been regarded as the moat coat-effective method to promote rapid infiltra- tion of water, keep soil on hillslopes and out of chan- nels and downstream areas (Miles and others 1989, Noble 1965, Rice and others 1965). Grasses are par- ticularly desirable for this purpose because their ex- tensive, fibrous root systems increase water infiltra- tion and hold Boil in place. Fast-growing non-native species have typicallybeen used. They are inexpensive and readily available in large quantities when an emergency arises (Agee 1993, Barro and Conard 1987, Miles and others 1989). Legumes are often added to seeding mixes for their ability to increase available nitrogen in the soil after the poatfire nutrient flush has been exhausted, aiding the growth of seeded grasses and native vegetation (Ratliff and McDonald 1987). Seed mixes were refined For particular areas as germination and establishment success were evaluated. Moat mixes contained annual grasses to provide quick cover and perennials to eatab- liah longer term protection (HIock and others 1975, Ratliff and McDonald 1987). However, non-native ape- cieathat persist can delay recovery of native flora and potentially alter local plant diversity. More recently BAER teams have recommended nonreproducing 11