Abstract: In accordance with one aspect of the present invention, there is provided a concave which has axially extending members and circumferentially extending members. With the round axially extending, members elevated, causing the crop to roll and break apart and a concave drop plate that serves as a reservoir to allowing much more even feeding of material across the entire width of the concave. The concave transfer plate allows a more efficient and complete separation process while reducing engine horsepower requirements, thus fuel consumption.

Abstract: An apparatus and method for improving the ability of a rotary combine to gently thresh a crop and to gently convey the crop through the threshing section of the combine. In a preferred embodiment, the invention is a crop engaging element for the rotor of a rotary combine, said crop engaging element comprising: a mounting structure having a ramp portion terminating in a top portion; a rasp bar comprising a base having a bottom surface and a curved convex top surface and a plurality of fins extending from said top surface; a leading mounting flange and a trailing mounting flange that extend from the mounting structure for mounting the crop engaging element to the rotor.