Synonyms: Blue Gum Tree, Stringy Bark Tree
Scientific Name: Eucalyptus globulus Labill.
Family: Myrtaceae (Myrtle Family)
Indigenous to south-western Australia and Tasmania
The eucalyptus is a majestic tree, with a greyish-white, peeling bark, which can grow to a height of 70 metres. Its characteristic feature are the elegant, sickle-shaped leaves which can be up to 30 cm long and which release the typical intensive aroma when rubbed. The narrow leaves hang down vertically to protect them from the strong heat of the sun. Eucalyptus forests are therefore sometimes called shadeless forests. If you hold a leaf up to the light you will see that it is studded with numerous tiny dots, the glands containing the essential oil. The young leaves at the tips of the branches are oval to heart-shaped, their upper surfaces bluish-green, the lower surfaces bearing a whitish coating. The flower buds are contained in capsules covered with a lid which springs open at the beginning of the flowering season revealing a corona of whitish-yellow stamens which has the appearance of a round brush. The fertilised flowers develop into stone-hard seed capsules. The Australian Blue Mountains in the hinterland of Sydney owe their name to the extensive, blue-shimmering eucalyptus forests.
The essential oil of the eucalyptus leaves inhibits the growth of bacteria and viruses, loosens thick mucus, is mildly antispasmodic, is deodorising and cooling. Drinking an infusion of eucalyptus leaves or inhaling with eucalyptus oil soothes sore throats, bronchitis and chronic bronchitis and loosens phlegm and relieves nasal congestion in colds. The essential oil is absorbed by the body and eliminated partly via the lungs. The cooling and mildly rubefacient eucalyptus oil is also contained in many ointments for treatment of rheumatism and gout.
The name eucalyptus is derived from the Greek words eu = good and kalyptos = enclosed and refers to the flower bud enclosed in a capsule with a lid that is thrown off as the bud opens. The epithet globulus = spherical describes the very rounded shape of the capsule lid.
The fast-growing eucalyptus is so thirsty that it can be used to dry out swamps. This quality has also given it the name Fever Tree. With the disappearance of the swamps the anopheles mosquito also disappears, and with it the fever of malaria. However, a positive quality in the wrong place can easily turn negative. In Europe, areas afforested with eucalyptus have become so dry and depleted that indigenous plants no longer stand a chance. Even the soil dwellers are driven away by the essential oils of the eucalyptus tree so unaccustomed in European parts.
Australia's native aborigines traditionally use eucalyptus leaves to treat fever, inflammation and injuries and to prevent cancer. In Ancient China eucalyptus was considered a remedy for pulmonary tuberculosis and asthma. The Europeans did not discover the eucalyptus tree for themselves until around 1790 during the first Australian expeditions of Captain James Cook. Eucalyptus trees have developed an amazing strategy for dealing with fire in order to survive in the Australian countryside with its frequent bush fires. Hidden deep down in the wood of the trunk and amongst the roots are shoots which only germinate when exposed to heat. They are linked to the outside world by channels which run through the wood to the surface of the bark. These channels contain plant hormones which are activated by heat and which awaken the shoots from their dormant state. When the fire has gone out young shoots sprout from deep down in the wood. The eucalyptus essential oil even fuels this remarkable survival strategy by feeding the fire and making it spread.
The sturdy eucalyptus wood makes good masts, railway sleepers, ship keels etc.
Koala bears feed mainly on eucalyptus leaves. But the furry little gourmets only eat the leaves of a few of the more than 600 eucalyptus species. This preference for eucalyptus is now threatening the existence of these marsupial Australian tree dwellers. To obtain agricultural land the white settlers in Australia have felled much of the eucalyptus forest and thus taken away the food basis of the koalas.
In Australia termites often attack the eucalyptus wood and hollow out the trunks from the inside. The resulting tubes are used by the aborigines as traditional musical instrument: the didgeridoo.
Eucalyptus essential oil is ideal for improving room air. Allow a little of the oil to evaporate in an aroma lamp or on an aroma stone to free the air from germs.