It is a very large evergreen tree, reaching up to 70 m (230 ft) tall and 4 m (13 ft) trunk diameter, with red-brown bark which peels in vertical strips. The leaves are arranged spirally, needle-like, 0.5–1 cm (0.20–0.39 in) long; and the seed cones globular, 1–2 cm (0.39–0.79 in) diameter with about 20–40 scales. It is superficially similar to the related Giant Sequoia (Sequoiadendron giganteum), from which it can be differentiated by the longer leaves (under 0.5 cm in the Giant Sequoia) and smaller cones (4–6 cm in the Giant Sequoia), and the harder bark on the trunk (thick, soft and spongy in Giant Sequoia).