A landscape roll layer attaches to a three-point hitch on a tractor. The container further comprises a clamp bridging over the depression and restraining the angular expansion of the depression, while at the same time enabling the depression to expand radially. The assess opening is covered by a tambour door having edges retained in tracks in the sidewalls of the storage box. Various embodiments, including an embodiment incorporating the analog functions as well as the primary digital functions of the read channel in a single integrated circuit, and preferred embodiments utilizing a reduced complexity, programmable modified Viterbi detector supporting a broad class of partial response channels are disclosed.