The sequoias have a matting, shallow, and wide-spreading root system. There is no tap root. They only root to 12 to 14 feet deep even at maturity. A mature sequoia’s roots can occupy over 1 acre of earth and contain over 90,000 cubic feet of soil. That mass of matted roots and soil has to maintain the equilibrium of a tree that is nearly 300 feet tall and weighs nearly 2 million pounds.