These are fairly typical looking Eucalypts or Gum Trees, photographed in the mountains of New South Wales. There are over 700 species of Eucalyptus, virtually all of them native to Australia, although a number of species are now grown all over the world. I can't remember which particular species these ones are.
It is mainly the Gum Trees that give the Australian bush its characteristic appearance. Economically they have become important globally. Most of the paper worldwide is made from Eucalyptus pulp, for example. If you've never tried Eucalyptus honey, you've missed out on a treat. Tasmanian Blue Gum Eucalyptus globulus is the most widely available because it grows all over the world, but I like Stringybark, River Red Gum, Ironbark and Yellow Box honeys too -- all Eucalypts.