Abstract: An all-earth foundation trencher has a digger body (1) pivotal selectively on a track-laying chassis (7). The digger body has an earth-mover blade (16) that is manipulatable multi-directionally on a front end. A digger boom (19) has a base end that is pivotal vertically forward from an aft end of the digger body. A digger head (22) is manipulatable on a digger end of the digger boom for power-digging foundation trenches having desired widths and depths in all likely consistencies of earth that ranges from hard and rocky earth to loose dirt. Conveyors (28–31) are positioned intermediate the track-laying chassis and the digger head for conveying removed earth sufficiently far from either or both sides of a foundation trench that the removed earth will not spill back into the foundation trench. A laser guide (99) proximate the digger head provides control assurance of accurate attitudinal digging. Operational controllers (102) include control knobs (104) on knob plates (49) positioned on a control panel (45).