This is known as a Rainbow Eucalyptus or "Painted Gum" tree. They are found all over Hawaii and are known by their smooth and colorful bark. These trees intrigued me a lot for some reason. The colored bark really got my attention. I took this top picture with the Sigma 10-20mm lens.
I don't know what kind of tree this one is, I didn't want to make the hike over to get a closer look. I was on vacation after all. I think it is another of the Rainbow Eucalyptus trees.
Both of these photos were taken on our drive to Hana on Maui.