Eucalyptus regnans, known variously as mountain ash, swamp gum, or stringy gum, is a species of Eucalyptus native to Tasmania and the state of Victoria in southeastern Australia. It is the tallest flowering plant and one of the tallest trees in the world, second to the coast redwood (Sequoia sempervirens). A straight-trunked tree with smooth grey bark and a stocking of rough brown bark to 5–20 metres (16–66 ft) above the ground, it regularly grows