Giant sequoias; sometimes included in the genus Sequoia; until recently placed in the Taxodiaceae WordNet 3.0 & Open English WordNet

Sequoiadendron is a genus of evergreen trees, with two species, only one of which survives to the present: Sequoiadendron giganteum, extant, commonly known as wellingtonia, giant redwood and giant sequoia, growing naturally in the Sierra Nevada of California † Sequoiadendron chaneyi, extinct, the predecessor of Sequoiadendron giganteum, found mostly in the Nevada part of the Tertiary Colorado Plateau until the late Miocene. Wikipedia