An agricultural undercut implement includes a frame carrying ground-engaging rolling means, a cutting disk arrangement to cut parallel slits in the ground soil, and an undercut assembly having upright cutting edges each aligned to follow a slit, and a transverse blade with a horizontal cutting edge disposed to undercut the ground soil between slits, as the frame rolls over the ground, such as when towed behind a tractor. The transverse blade is configured to sever the strip of ground soil undercut by the cutting edge, and then move the undercut soil strip up and over the blade before replacing it intact on the ground. A method of agricultural crop management includes non-terminatingly retarding the growth of a permanent cover crop by using the implement to undercut and replace intact the ground soil beneath the cover crop. Some examples include drive units configured to drive blades through pluralities of blade positions.
