The River Red Gum tree or Eucalyptus camaldulensis is native to Australia. Very early in the development of the Arizona desert, eucalyptus trees were planted in large numbers. But they have now gone out of favor because of their size and the tendency to break off limbs in storms. They are also considered to be untidy but current landscapers and hardly ever used in new plantings. Slowly, the older trees are starting to disappear.