Sequoia sempervirens
Common name: Coast redwood, California redwood
Sequoia sempervirens is an evergreen tree and a member of the cypress family. It is the tallest tree in the world, as well as one of the most ancient. It is native to the Pacific coast, from southern Oregon to the California Bay Area.
Researcher Steve Sillett has studied the canopies of old-growth redwood forests. He discovered that they create new ecosystems where many plants and wildlife thrive high above the ground. In fact, so many smaller redwoods grow in the canopy that it is virtually a forest within a forest. Baby sequoias grow on high branches and nurture smaller baby trees, which in turn nurture even smaller babies. This pattern is called a 'fractal' or a 'reiteration.' More about the research. More about the genus name Sequoia.
Full tree photo via Wikimedia Commons