Several expressions for characterizing bed roughness produced by a layer of saltating sediment have previously been proposed, and another is presented herein. These expressions relate the magnitude of the bottom roughness to the thickness of the near-bed layer of saltating particles. In two previous studies, the empirically set constant of proportionality was determined using data for which the roughness assciated with bed forms had to be calculated and subtracted from the total observed roughness, the remaining roughness being attributed to bed load. In this paper the expressions for bottom roughness are tested against values observed in upper plane bed flows where the transport is high and the bed is nearly flat. The results indicate that the two expressions in which the coefficient of proportionality was set using data requiring removal of bed form roughness overpredict the observed roughness by roughly 2 orders of magnitude, whereas the other two equations show good agreement with the measurements. The equations that overpedict the roughness may have attributed the roughness of small bed forms to bed load. ¿ American Geophysical Union 1989