A harvesting header includes a header frame, a flexible cutterbar assembly, and a draper assembly. The cutterbar assembly is mounted to the header frame and includes a plurality of skids. Each of the skids has a lower margin configured to engage the ground such that the skids cooperatively cause flexing of the cutterbar assembly along the length thereof in response to changes in terrain as the header is advanced. Each skid presents a skid surface extending from the lower skid margin.