ARS | Publication request: Effectiveness of postfire erosion control treatments

Submitted to: International Soil Conservation Organization Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: May 14, 2006
Publication Date: May 14, 2006
Citation: Robichaud, P.R., Pierson, F.B., and Wagenbrenner, J.W. 2006. Effectiveness of postfire erosion control treatments. In: Proceedings of the 14th Conference of International Soil Conservation, May 14-19, 2006, Marrakech, Morocco. (CD-ROM)

Interpretive Summary: Wildfires can affect soil stability on millions of acres of western forest and range land in any given year. These wildfires greatly increase the likelihood of excessive soil erosion and runoff in the period before vegetation recovery. In this study, alternative erosion mitigation treatments were implemented in the immediate year following wildfire in Washington, California, Montana and Colorado. Most treatments studied showed significant reductions in site erosion for small rainfall events, but not for larger events. These data quantify potential gains in erosion control from mitigation treatments and can be used by land managers to assess erosion risk and potential benefits from alternative post-fire management strategies.

Technical Abstract: To mitigate potential postfire erosion and flooding, various erosion control treatments are applied on highly erodible areas with downstream resources in need of protection. Recent efforts to evaluate the effectiveness of postfire erosion mitigation treatments have used natural rainfall experiments at the hillslope and small watershed scale. Preliminary results suggest that some mitigation treatments may help reduce erosion for some, but not all, rainfall events. For small rainfall events, reduction in first year erosion rates have been measured for contour-felled logs erosion barriers (50-70%), engineered wood straw (78%), straw mulch (60-80%), and hydromulch (19%). Grass seeding treatments have little effect on first year erosion reduction. For intense rain events (I10 greater than 40 mm/h) there was little difference between treated and non-treated areas.