A concave includes a frame and an array of threshing elements supported by the frame, the threshing elements being spaced apart and extending generally parallel to one another. The threshing elements each have formed on an upper portion thereof disposed adjacent to an upper portion of the frame a longitudinally-extending notch respectively defining an aggressive threshing edge. The threshing edges faces a direction opposite to the direction of rotation of a harvester rotor. The notch is recessed into the bar and disposed adjacent to the upper portions of the opposite members of the frame and facing opposite to a direction of movement of the rotor. The notch has a channel along an outer edge of the notch, the channel being filled with filler material having a differing hardness than a hardness of the bar.
