Once tree roots have penetrated a drain, blockages will surely follow. The roots form a tough mesh that begins to block the drain by trapping solid matter. High pressure jetting will often break a hole in the root ball temporarily restoring flow. However over time the roots will re-grow and the problem will recur so drain root cutting offers a long-term solution.
A better solution is to cut the roots out with a root cutter as shown. The cutting blade is powered by high pressure water and rotates to cut the roots where they enter the pipe. The blades are interchangeable allowing us to clear roots from large diameter drains too. Depending on the type of tree, even with drain root cutting, the roots may return over time meaning that drain repair would be necessary as well.