The effects of three tillage treatments-rough-, fine- and zero-tilled-on rill erosion of a bare, self-mulching black earth were tested to determine whether tillage practices could reduce susceptibility of such soils to entrainment and transport by overland flow. In contrast to reported results for a silt loam soil, rill erosion was greatest for zero-tilled soil, and similar for the two tilled treatments. Sediment size distributions were independent of initial dry aggregate size distributions. It seems that, for self-mulching soils, stubble retention is the only method available to increase resistance to erosion by overland flow.