Effects of Livestock Grazing on Infiltration and Erosion Rates Measured on Chained and Unchained Pinyon-Juniper Sites in Southeastern Utah

Abstract

This study was conducted on sandy loam soils in southeastern Utah during summers of 1971 and 1972. Forage removal and soil compaction had no consistent effect on infiltration rates. However, the clipping and compaction were an instantaneous application of forage removal and soil pressure and thus may not adequately represent long term, accumulative conditions imposed by actual grazing. Areas rested from livestock grazing since 1967 had significantly higher infiltration rates than grazed areas on unchained woodland and chained, debris-in-place sites. Grazed plots had infiltration rates comparable to rates measured on areas protected from grazing since 1969 or 1971. Grazing did not consistently affect infiltration measured on chained, debris-windrowed sites. Infiltration rates increased on all sites as the period of rest from grazing increased. None of the 21 soil and vegetation variables included in this study were identified by multiple regression models as consistently explaining significant amounts of variation in infiltration rates. Interrill or sheet erosion rates were not significantly affected by forage removal subtreatments. No consistent relationship between erosion rates and soil compaction subtreatments or various periods of rest from grazing was found.