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(135 m3 ha 1), using a high density of logs. Iffirst-year annual erosion rates vary from 0.004 to 150 t ac 1 (0.01 to 370 Mg ha 1) then they could trap 5 to 47 percent of 150 t ac 1 (370 Mg ha 1) of sediment, depending on the density of the loge. Beyond that they would not be coat effective from asediment-holding capacity analysis. This wide range of effectiveness indicates the need of proper estimation techniques of the erosion potential, and for properly designing con- tour-felled log installations in terms of log numbers and spacing. For example, ifyou can trap 60 percent or greaterthentheyareprobablycosteffective,butifyou are only trapping 5 or 10 percent of the expected sediment production, then it may not be worth the effort for such small amount of sediment storage ability. Contour-felled loge do provide immediate ben- efits after installation, in that they trap sediment during the first poatfire year, which usually has the highest erosion rates. The ability of this treatment to reduce runoff, tilling, increase infiltration and decrease downstream time to peak (slowing velocities) has not been docu- mented, even though these are reasons often given for doing contour felling. Ifcontour-felled loge slow or eliminate runoff, sediment movement may not occur. Therefore, measuring sediment accumulationbehind the loge may not be the best method for assessing their effectiveness. Quantifying sediment and water output from a watershed are the beat ways to truly evaluate the effectiveness ofcontour-felled logs, but this kind ofresearch and monitoring is expensive and difficult to do. Contour-felled loge will channel flow if not installed correctly on the contour with good ground contact. There- fore, propertraining, contractinspections,and close moni- toring during installation are critical to success, as was repeatedly pointed out by interviewees (appendix B). Grass seeding is the moat widely used and best studied BAER treatment. Our interviewees ranked seeding second highest in overall treatment prefer- ence, despite giving it mixed reviews for effectiveness and citing it as overused more often than any other treatment. Expenditures for seeding declined eome- what in recent years (fig. 1?). However, seeding re- mainathe only method available to treat large areas at a reasonably low coat per acre. How likely is seeding to increase plant cover or reduce erosion, in either the first growing season or later? We tabulated results from published studies (in tables 6 and 7) to determine rough probabilities of eeeding "success" in the first and second years after fire (table 19). Only studies that evaluated compa- rable seeded and unseeded plots were included. Die- tinct research sites within a single paper were treated as unique "atudiea° for this wmparison. Because few researchers measured erosion, we used vegetation cover as an indicator of potential erosion control effec- tiveness. Previous work found that 60 percent ground cover reduced sediment movement to negligible amounts, and 30 percent cover reduced erosion by about half compared to bare ground (Noble 1965, Orr 1970). We used these levels as indicators ofeffective or partly effective watershed protection, respectively, from seeded and/or natural vegetation. Table 18-NUmbeB of published studies reporting measures of seading'success' by native vegetation type during the first 2 years following fire Pubs. Showing Cover Measure mentst These Showing Seeding Increased Cover %of Pubs >30 % Seeded . Showing Cover Unseeded %of Pubs. Showing >60 % Cover Seeded Unseetled Pubs. Showing Erosion Measure menu Those Showing Seeding Reduced Erosion ______________ Atp,-_____________ ________ ________Percent_______________ ________.___ Aro, _.____.___._ Poatfire Year One Chapanal 10 4 50 50 30 20 7 1 Conifer 9 5 33 0 22 0 1 0 Combined 19 9 42 26 26 10.5 8 1 PoslSre Year Two Chapanai 7 2 86 86 86 43 6 1 Conier it 8 73 55 36 0 3 1 Combined 18 8 78 67 56 17 9 2 'All studies contelned aeetled end unaeeded plots end reponetl plant productlan es permm cover al the end of the growing season. Only atatlsilmlly signiflmnt increases In coveror reductbns in erosion eretebulaled (Amaranthus 1989, Amerenihus and ofhe~s 1993, Anderson end Brooks 1975, Boyers endothers 1998e, Conant and olhera 1995, Gabler 1963, Geler•Hayes 1897, GrHBn 1982, Rim and others 1965, Roby 1989, 7eskey and others 1969, Van de Water 1999, Tledemann end 19ock 1873, 1976). 48 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-63.2000