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Table 20-Numbers of monitodng reports listing measures of seeding'success' by native vegeta8on type during the first 2 years following fire. Reports Showing Those Showing % of Reports Showing % o} Reports Showing Reports Showing Those Showing Cover Seeding Increased >30 % Cover a80 % Cover Erosion Seeding Reduced Measurements) Cover Seeded Unseeded Seeded Unneeded Measurements Erosion PosMre Year One Chaparral 7 4 85 25 38 12 3 1 Conifer 4 3 60 60 30 0 4 2 Combined 11 7 74 38 35 8 7 3 Chaparral Poelflre Year Two 2 0 67 67 Con'rfer 0 0 80 100 Combined 2 0 75 75 33 33 2 0 20 100 1 1 25 50 3 1 tThe first twc columns report ony studies that mntalned both seeded end unneeded plots. The middle four mlumna aummadze all studies that contained percem vegeteaon cover data. The last Iwo columns repod ony swdles that compared erosion iretween seeded and unseeded plots. Stadadcal slgniflcence was not tested In mesa awmea Interviewees and monitoring reports alike acknowl- edgedthat the major benefits ofaeeding are net appar- ent until the second year after fire, because, as noted above (Amaranthua 1989), most of the growth by seeded grasses takes place after first year damaging storms have occurred. From the Los Padres National Forest: "Aa is typical, the seeding [annual ryegrasa and lane vetch] did not significantly control erosion during the first rainy season. Seeds did not germinate until after steady precipitation, and did not grow significantly until after warm spring weather. The seeded species are expected to be of greatest value during the second and third rainy seasons" (Eaplin and Shackleford 1978), when plant litter produced by the first year's growth covers the soil. Rainfall that first winter was the second hipheat on record and resulted in approximately 125 yd ac 1(240 m3 ha 1) of soileroded, despite thefactthatseedingwas"aucceas- ful" by moat criteria, tripling average plant biomass compared to unaeeded areas by the end of the first growing eeason (Eaplin and Shackleford 1978). One report suggested that measures other than seeding should be used in places where first-year control of sediment movement is critical (Ruby 199?). The in- creased use ofcontour-felled loge in recent years prob- ably reflects this knowledge. Seeding is often moat successful where it may be needed least-on gentle elopes and in riparian areas. Janicki (1989) found thattwo-thirds ofplota with more than 30 percent annual ryegrasa cover were on slopes of less than 35 percent. He also noted "observations of grace plants concentrated in drainage bottoms aug- geat that seed washed off the elope with the first two storm events." Concentration of seeded species at the base of slopes was also observed by Loftin and others (1998). Some published papers and most monitoring reports did not give slope angles for study sites, mak- ing interpretation of varying success levels dit&cult. Severalintervieweea suggested that seeding was un- necessaryinriparian areas, because native vegetation there usually recovers rapidly. On the other hand, other published papers and monitoring reports aug- geated quickly establishing stripe of vegetation along the margins of streams ae one of the beat ways to reduce sediment transport into watercourses. Careful assessment of vegetation regrowth potential during the BAER evaluation could help resolve this apparent contradiction. Interviewees observed that first-year seeding auc- cesais highly dependent on rainfall pattern. Gentle rain before the first intense storm is needed to stimu- late germination; then enough rain is needed for seeded species to survive. These conditions are more likely to be met in some areas of the Western United States than others. Seeding may be particularly risky in the Southwest (Region 3), where intense monsoon rains follow the early summer fire season. Areas where seeding is more often considered "excellent" or "good" maybe those where rainfall lastalonger through the year (e.g., all but July and August in the Pacific Northwest) or where a significant portion of the an- nual total occurs in summer (e.g., about 30 percent in areas such as Montana, northern Idaho, and north- easternWashington). California (Region 5) has a long dry season and unpredictable early fall rains, making grass establishment less likely to be successful. 50 USDA Forest Service Gen. Tech. Rep. RMRS-GTRE3. 2000