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Contour Felled Logs--This treatment involves fell- ing loge on burned-over hillsides and laying them on the ground along the elope contour, providing me- chanical barriers towater flow, promoting infiltration and reducing sediment movement; the barriers can also trap sediment. The terms "log erosion barriers" or "log terracettea° are often used when the logs are staked in place and filled behind. Logs were contour- feIled on 22 ac (9 ha) of the 1979 Bridge Creek Fire, Deschutes National Forest in Oregon (McCammon and Hughes 1980). Trees 6 to 12 in (150-300 mm) d.b.h. were placed and secured on slopes up to 60 percent at intervals of 10 to 20 tt (3 to 6 m). Loge were staked and holes underneath were filled. After the first storm event, about 63percent ofthecontour-felled logs were judged effective in trapping sediment. The remainder were either partially effective or did not receive flow. Nearly 60 percent of the storage space behind con- tour-felled loge was full to capacity, 30 percent was half-full, and 10 percent had inaignifieant deposition. Common failures were flow under the log and not placing the logs on contour (more than 25° off contour caused trap efficiency to decrease to 20 percent). Over 1,600 yd3 (1,225 m3) of material was estimated trapped behind centaur-felled loge on the 22 ac or about 73 yd3 ac 1(135 m8 ha ').Only 1 yd3 (0.7 m~) of sediment was deposited in the intake pond for a municipal water aupplybelow. Miles and others (1989) monitored contour-felling on the 1987 South Fork Trinity River fires, Shasta-Trinity National Forest in California. The treatment was applied to 200 ac (80 ha) within a 60,000 ac (20,240 ha) burned area. Trees <10 in (250 mm) d.b.h. spaced 15 to 20 ft (4.5 to 6 m) apart were Felled at rate of 80.100 trees ac 1 (200- 250 trees ha 1). The contour-Felled loge trapped 0 to 0.07 yd3 {0 to O.Ob mg) of soil per log, retaining 1.6 to 6.7 yd3 ac 1(3 to 13 m3 ha 1) of soil onsite. Miles and others (1989) considered sediment trapping efficiency low and the coat high for this treatment (table 8). Sediment deposition below treated areas was not measured, however. Contour Trenching-Contour trenches have been used as a BAER treatment to reduce erosion and permit revegetation of fire-damaged watersheds. Al- though theydoincreaseinfiltration rates, the amounts are dependent on soils and geology (DeByle 1970b). Contour trenches can significantly improve revegeta- tion by trapping more snow, but they don not affect water yield to any appreciable extent (Doty 1970, 1972). This BAER treatment can be effective in alter- ingthe hydrologic response from short duration, high intensity storms typical of summer thunderstorms, but does not significantly change the peakflowe oflow intensity, long duration rainfall events (DeByle 1970a). Doty (1971) noted that contour trenching in the sagebrush (Artemisia app.) portion (upper 15 percent with the harshest sites) of a watershed in central Utah did not significantly change streamflow and atormflow patterns. The report by Doty (1971) did not discuss sediment. Coatales and Costalea (1984) reported on the use of contour trenching on recently burned steep slopes (40 to 50 percent) with clay loam soils in pine stands ofthe Philippines. Contour trench- ing reduced sediment yield by over 80 percent, from ZS to 5 t ac 1(63 to 12 Mg ha 1), Other Hillslope Treatments-Treatments such as tilling, temporary fencing, installation of erosion control fabric, use of straw wattles, lopping and scattering of slash, and silt fence construction are used to control sediment on the hillslopea. No pub- lished quantitative information is available about the efficiency and sediment trapping ability of these treatments after wildfires. Channel Treatmettts--Channel treatments are implemented to modify sediment and water move- mentinephemeral or amallrorderchannels, toprevent flooding and debris torrents that may affect down- stream values at risk. Some in-channel structures slow water flow and allow sediment to settle out; sediment will later be released gradually as the struc- ture decays. Channel clearing is done to remove large objects that could become mobilized in a flood. Much leas information has been published onchannel treat- ments than on hillslope methods. Straw Bale Chcrk Dams-Miles and others (1989) reported on the results of installing 1300 straw bale check dams after the 1987 South Fork Trinity River fires, Shasta-TrinityNational Forest, California. Most dame were constructed with five bales, About 13 per- cent ofthe straw bale check dame failed due to piping under or between bales or undercutting of the central bale. Each dam stored an average 1.1 yd3 (0.8 mg) of sediment. They felt that filter fabric on the upside of each dam and a spillway apron would have increased effectiveness. They considered straw bale check dams easy to install and highly effective when they did not fail (table 8). Collins and Johnston (1995) evaluated the effectiveness of straw bales on sedi- ment retention after the Oakland Hills fire. About 5000 bales were installed in 440 straw bale cheek dame and 100 hillslope barriers. Three months after installation, 43 to 46 percent of the check dams were functioning. This decreased to 37 to 43 percent by 4.5 months, at which time 9 percent were side cut, 22 percent were undercut, 30 percent had moved, 24 per- centwere filled, l2 percent were unfilled, and 3 percent were filled but cut. Sediment storage amounted to 55 yd3 (42 mg) behind straw bale check dams and another 122 yd3 (93 m3) on an alluvial fan. Goldman and others (1986) recommended that the drainage area for straw bale check dams be kept to less than 20 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-63.2000