Giant sequoia is the sole living species in the genus Sequoiadendron. They are the world's largest trees in terms of total volume. They grow to an average height of 50–85 metres (160–279 ft) and 6–8 metres (20–26 ft) in diameter. Record trees have been measured to be 94.8 metres (311 ft) in height and over 17 metres (56 ft) in diameter. The oldest known giant sequoia based on ring count is 3,500 years old. The natural distribution of giant sequoia is restricted to a limited area of the western Sierra Nevada, California.