genus of conifers of the bald cypress family (Taxodiaceae), comprising one species, Sequoia sempervirens ( redwood). The big tree, or giant sequoia (Sequoiadendron giganteum; see photograph-->), historically was included in this genus. The redwood is native in the fog belt of the Coast Ranges from southern Monterey county, Calif., to southern Oregon, U.S., and the big tree occurs in scattered groves on the westerly slopes of the Sierra Nevada from Placer to Tulare counties in California. Fossil remains of Sequoia as old as the Jurassic Period (about 200 to 145.5 million years ago) are widely dispersed in the Northern Hemisphere. The bald cypress (Taxodium distichum) and dawn redwood (Metasequoia glyptostroboides) are closely related to Sequoia. The generic name commemorates the great Cherokee Indian Sequoyah (or Sequoya).