The redwood — aka Sequoia sempervirens — is California's official state tree, and it's not hard to see why. The tallest tree in the world is a coastal redwood named Hyperion in Redwood National Park. Sequoias are the most common type of tree found in California, and there's even a national park dedicated to them.
Giant sequoias, with massive trunks and vertical height so tall you may get vertigo by standing at their base and looking up, are something of a California treasure. Apple could very well choose to name its next operating system sequoia, for the tree's natural magnificence and grandeur.