A. Kapoor and C.F. Shaykewich, University of Manitoba

Quantifying losses due to soil erosion was the basis of this six-year soil scalping experiment developed on six Manitoba soil types. Soil textures ranged from a Willowcrest fine sand to a Pembina clay loam. On a completely randomized split plot design, topsoil removal was the main plot treatment and varying fertilizer application was the subplot treatment. Data showed yields to be severely depressed on all topsoil removal treatments where no fertilizer was applied. On the coarse textured soils even twice the recommended rate of fertilizer was not able to bring the yields back to that of the control. The recommended rate of fertilizer application was able to mitigate topsoil losses on fine textured soils and in some cases yields exceeded the control at twice the recommended rate of fertilizer. Data from the six years is being used to model the productivity losses due to simulated soil erosion.