These photos (clickable to original sources) are of a real life tree! I just found out about this today and was angry that it hadn't been brought to my attention earlier. Clearly this is the most beautiful tree in the world, and is called Eucalyptus Deglupta. In a nutshell, the bark is shed periodically and reveals bright green inner bark. As it matures, the color changes to blue, purple, orange, and maroon (thanks wikipedia). Shockingly, this tree is cultivated mostly for pulpwood to make paper. I can only assume that these colors don't preserve well, otherwise i would build my entire house with it.