My wife and I (her idea, my braun), are going to put in a hedge row of Schip Laurels. The run will be about 30-40 feet long and will be planted in the rocky clay soil that we have here in Middle Tennessee. My first thought was to use a powered trencher to do the heavy work. Once the soil is at least broken up, I should be able to dig the holes for the rather large (3-4) foot shrubs with a shovel. My plan is to do a few parallel passes, but my fear is that this may not be feasible. The trencher that I plan on renting has tracks, not wheels, so that should help some. Has anyone done something similar to this? Or does anyone have any trencher advice? I'd rather not use an auger to dig individual holes it at all possible.