Date of this Version
Fire Science Brief, Issue 69, September 2009
A pair of major wildfi res in the Front Range of Colorado in 2002 created an ideal opportunity to measure post-fire soil erosion characteristics and to assess the effectiveness of various site rehabilitation treatments to reduce erosion. The studies continued over a four-year period, allowing collection of data on longer-term erosion and sedimentation trends. Most erosion in this region is caused by localized convective thunderstorms rather than snowmelt runoff. Sedimentation measurements documented that straw mulch and to a limited extent hydromulch were effective in reducing post-fire erosion by increasing the amount of ground cover. Seeding following scarifi cation and application of a polyacrylamide (PAM) spray had little to no effect on post-fire erosion rates. Erosion in the fire study areas in some cases has not yet returned to background levels. Percentage of ground cover was shown to be the predominant control on post-fire erosion. Research indicates that current erosion predictive models are valuable for estimating average sediment yield, but less effective for forecasting soil loss from individual slopes.