
Here is one such log. It appears that the rest of this tree was harvested and the top section was left behind as slash. The limbs have long since rotted away and broken off along with most of the sapwood.
With a minor amount of chainsaw work, a piece of cedar like this is easily converted to a planter box. The process starts with an examination of the material in order to identify structural weakness (checking and splitting) and the most aesthetically interesting surfaces. Once this was determined, this log was put on the WoodMizer band saw, and one shallow cut was made to establish a flat bottom. A chain saw also makes short work of this step if you don't have a mill handy. Snap a chalk line and rotate the stock 90 degrees so you can stand over the log holding the saw bar angled down parallel to the plumb line. Accuarcy is not terribly important here.

Since the inside of this log was already mostly hollow, or at least extremely weakened by rot, it was very easy to cut a channel down the top, the length of the log, and then remove the rotted material down to solid heartwood.
Every 18" or so an indentation is chiseled out about 1 1/2" deep and a 1 1/2" hole is drilled in the center with a forstner bit for drainage. The chiseled indentation is filled with drain rock to hold back the soil and keep the drain holes open.

End caps for this planter are cut to match the shape of each end of the log. This is an excellent use for short scraps left over from other projects. In this case, some rough cut 1 1/8" cedar was pulled from the kindling pile, cut to shape, and attached with 30 penny galvanized spikes. A few handfuls of 3"- drain rock and some dirt and this project is finished. It will NEVER need sanding or refinishing and is best placed in a suitable location for shade plants as this will encourage the moss to continue growing and further enhance the appearance of this one-of-a-kind planter box.