How to Trench Around Oak Tree Roots

Measure the distance from the tree trunk to the drip line, and note that distance. Walk out from the tree – starting at the drip line -- for one-third to one-half that distance. Drive a stake into the ground, 6 to 8 inches deep, to mark that spot.

Walk out from the drip line all around the tree, repeating this process, about 10 to 12 times. Create a large circle around the tree by stringing colored plastic barricade tape or twine from stake to stake, attaching it to each stake.

Avoid running construction or utility trenches through the root protection zone, which protects crucial roots. Mark the path – or paths – of trenches planned near the oak. Reroute these if possible. Consolidate multiple trenches into one, alternatively.

Use the trencher to dig trench lines beyond the root protection zone. Dig the trench extension within the root zone by hand -- using the pick axe and shovels -- to avoid severing any major roots. Use a power auger, alternatively, to create tunnels to run conduit and utility lines under and around important roots.

Cut cleanly any and all roots that may have been severed or torn during trenching or boring. Refill trenches and tunnels as soon as possible, to avoid drying out the tree roots. Thoroughly water the entire root area, giving the tree a deep soaking.