A rotating disc assembly for use on a stump grinder that can include: a rotating disc member having a peripheral edge and defining a central axis and a radial direction; a bit securing sub-assembly comprising a bit holder member mechanically connected to the rotating disc member and having a first portion extending in a first direction, and a second portion extending from said first portion along a second direction that is not parallel to said first direction; a bit mechanically connected to the bit holder member by a fastening hardware; and a first portion of the peripheral edge extending a further distance in the radial direction than a second portion of the peripheral edge; wherein the bit and the bit securing sub-assembly are sized, shaped, located and/or connected so that the first bit is at least partially shielded by a footprint of the first portion of the peripheral edge.
