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of planted pine seedlings had significantly greater survival and lower water stress on seeded plots than on controls. By then, dead ryegrass formed a dense mulch on the seeded plots, but no live grass was found. Native shrub cover was significantly greater on the unaeeded plate the second year and soil moisture was lower (Amaranthua and others 1993). Ryegrase thus acted as a detrimental competitor to tree seedlings the fast year after fu•e, but provided a beneficial mulch and reduced competition from woody plants the sec- ond year. Canard and others (1991) also suggested that seeded ryegrasa could benefit planted conifer seedlings if it suppressed woody competitors and could itself later be controlled. In their study, how- ever, live ryegrass cover was exceptionally high in many plots during the second year after fire (Canard and others 1991). The studies examined suggest that grass seeding does not assure increased plant cover during the first critical year after fire (table 6). A wide variety of grass species or mixes and application rates were used in the reported studies, making generalization difficult. Over 50 years ago, southern California for- esters were urged to caution the public not to expect significant first-year sediment control from postfire seeding (Gleason 1947). Better cover and, conse- quently, eroaioncontrol can be expected in the second (table 7) and subsequent years. Measuringeroaionand rtmoffisexpensive, complex, and labor-intensive, and few researchers have done it. Such research is necessary to determine if seeded grasses control erosion better than natural regenera- tion. Another goal of postfu~e grass seeding on timber sites, soil fertility retention, dcea not appear to have been investigated. Grass establishment can clearly interfere with native plant growth, and grass varieties that will suppress native shrubs but not conifer seed- lingshave not yet been developed (Ratlif t'and McDonald 1987). The impacts of recent choices for rehabilitation seeding, includingnative grasses and cereal grains, on natural and planted regeneration in forest lands have not been studied extensively. Mulch-Mulch is material spread over the soil sur- face to protect it from raindrop impact. Straw mulch applied at a rate of 0.9 t ac 1(2 Mg ha 1) significantly reduced sediment yield on burned pine-shrub forest in Spain over an 18-month period with 46 rainfall events (Bautista and others 1996). Sediment production was 0.08 to 1.3 t ac 1(0.18 to 2.92 Mg ha 1) on unmulched plots but only 0.04 to 0.08 t ac 1(0.09 to 0.18 Mg ha 1) on mulched plots. Kay (1983) tested straw mulch laid down at four rates--0.5, 1, 1.5, and 4 t ac 1(1.1, 2.2, 3.4, and 9.0 Mg ha 1}-against jute excelsior, and paper for erosion control. Straw was the most coat- effective mulch, superior in protection to hydraulic mulches and comparable to expensive fabrics. Excel- sior was leas effective but better than paper strip synthetic yarn. The beat erosion control came from jute applied over 1.5 t ac 1(3.4 Mg ha 1) straw. Miles and others (1989) studied the use of wheat straw mulch on the 1987 South Fork of the Trinity Riverfire, Shasta-Trinity National Fareet in California. Wheat straw mulch was applied to fill elopes adjacent to peren- nial streams, fuelines, and areas of extreme erosion hazard. Mulch applied at rates of 2 t ac 1(4.6 Mg ha 1), or 1 t ac 1(s.2 M~ ha-1) on largser areas, reduced erosion 6 to 10 yd ac (11 to 19 m ha ). They considered mulching to be highly effective in controlling erosion (table 8). Edwards and others (1995) examined the effects of straw mulching at rates of 0.9,1,8, 2.7, and 3.6tac 1(2,4,6,and8Mgha 1)on5to9percentslopea. Soil lose at 0.9 t ac 1 (2 Mg ha 1} mulch was signifi- cantly greater (1.4 t ac 1, 3.16 Mg ha 1 of soil) than at 1.8 t ac 1(4 Mg ha 1) mulch (0.9 t ac 1,1.81 Mg ha 1 of soil lose). Above 1.8 t ac 1(4 Mg ha 1) mulch there was no further reduction in soil loss. Table B--Comparison of slope and channel BAER treatments, South Fork Trinity River fires, Shasta-Trinity National Forest, CA, 1987 (modified from Miles et al. 1989). Costs are shown in 1999 dollars. Cost Efficacy Install Treatment Type ($ y ) ($ m ) ($ ac) {$ ha) Category Rate Risk of Failure ------- -------$$7999------ -- - --- Scope Treatment Summary Aerial Seeding $23 $23 $79 $196 Modeate' Rapid Moderate Mulching $50 $52 $504 $1245 H(gh2 Slow Low Contour Felling $180 $183 $720 $1778 LowZ Slow High Channel Treatment Summary Straw Bale Check Dams $105 $107 $158 $392 Highz 2 High Low Log and Rock Check Dams $33 $33 $1346 $3325 HIgh Slow Moderate Soil loss estimated using Universal Soil Loss Equation (LISLE). SSoil loss estimated using on-site measurements. USDA Forest Service Gen. Tech. Rep. RMRS-GTRfi3.2000 19