Abstract: The document discloses a disc tool (1) for breaking up field residues, comprising a central hub portion (10), which is designed for mounting the disc in a tool holder in order to make the disc rotatable about a rotation axis (Ar), a cultivating portion (11), which is located radially outside of and adjoins the hub portion (10), and a plurality of substantially straight cutting edges (E1, E2) which are located at the periphery of the disc tool. The cultivating portion (11) has a plurality of undulations (111, 112) which, with an axial extent decreasing toward the inside, run from the cutting edges (E1, E2) to the hub portion (10). The cutting edge (LE1, E2) is designed such that 90-98% of a track formed by the cutting edge consists of straight track portions. The document further discloses an agricultural implement with such disc tools, the use of such an agricultural implement, and a method for manufacturing such a disc tool.