How to Use: The first use a hammer to bash away the bark on some roots near the base of the tree , to do is drive a few of them directly into roots, in holes you've first drilled with the bit. Then you drive the rest of the spikes into the stump around the base of the tree close to the ground, and not all around the top of the stump. They have been used for this problem traditionally and work nicely - a low-stress solution to trees with roots that keep invading the plumbing.