Abstract: An earth-working tool has mounting means at one end for attachment of the tool to the frame of an agricultural implement, a tool blade down the forward edge of the tool and attachment means at the other end of the tool for securing a tool point. The mounting means is so arranged that the tool may be attached to the frame in such a manner that the tool blade will form a rearward angle, from the top end to the other end, in relation to a line normal to the direction of forward movement which the tool will take during use, with the result that soil tilled by the tool point will be prevented from rising to the surface by the action of the rearwardly directed tool blade. Ideally the tool may be mounted so that the tool blade will be forwardly directed, either by reversing the tool or by providing alternative mounting holes for mounting the tool to an agricultural implement.