To describes the transport of cohesive sediments, it is necessary to specify the erosion flux at the bed. Experiments on the erosion of soft mud layers in a steady flow were performed in the Delft Tidal Flume and in an annular flume. The results were analyzed using the erosion rate function as derived by Parchure and Mehta. It is concluded that a resonable description is possible. However, the floc erosion rate appeared to be a function of the bed shear stress. In one case the erosion rate function needed to be adjusted slightly in order to obtain agreement between measured and calculated suspension concentrations. ¿ American Geophysical Union 1989