The tree is indigenous with a few exceptions to Australia and Tasmania. The genus contains about 300 species and is one of the most characteristic genera of the Australian flora. The leaves are leathery in texture, hang obliquely or vertically, and are studded with glands containing a fragrant volatile oil. The fruit is surrounded by a woody, cupshaped receptacle and contains numerous minute seeds. Eucalyptus trees are quick growers and many species reach a great height.
Many species yield valuable timber, others oils, kino, etc.
There are a great number of species of Eucalyptus trees yielding essential oils, the foliage of some being more odorous than that of others, and the oils from the various species differing widely in character. It necessarily follows that the term Eucalyptus oil is meaningless from a scientific point of view unless the species from which it is derived is stated. The Eucalyptus industry is becoming of economic importance to Australia, especially in New South Wales and Victoria. Many of the old species which give the oil of commerce have given way to other species which have been found to gave larger yields or better oils. About twenty-five species are at the present time being utilized for their oil.