Eucalyptus

The genus Eucalyptus makes up nearly 3/4 of Australia's total number of plant species. In the late 1700's, early botanists first tackled the job of describing more than 500 species of eucalyptus trees. The job isn't yet complete. New varieties and hybrids are still being discovered, and old classifications are being revised.

The genus name is derived from the Greek EU, meaning 'well', and kalyptos, meaning 'cover'. Eu kalyptos refers to the well-covered flower buds, which are cone shaped and have a lid-like structure that opens as the flowers mature. Aroma therapists and over-the-counter pharmaceutical manufacturers might take the name to mean that Eucalyptus covers well a variety of common conditions. Aroma therapists use the oil for its energizing, clarifying aroma. Lots of the colds and flu preparations available - cough drops, throat lozenges and chest rubs - contain eucalyptus oil and its derivatives.

Eucalyptus trees are known as gum trees because they exude a sticky, tannin-rich substance known as kino. Thanks to its astringent properties, kino has a history of medicinal use. At one time it was also used as a tanning agent in the manufacture of leather goods.

Another common name for eucalyptus is fever tree. In the19th century British colonists, noting the fragrant, medicinal aroma of eucalyptus groves, planted the trees in tropical fever ridden districts throughout the Empire in an effort to drive away insects and contagious diseases. An added plus (in the colonists' eyes) was that the trees also tended to dry out water-logged soils with their extensive, hungry root systems, making marshy soils into arable, habitable land. This deterred disease-carrying insects, especially mosquitoes, which need standing water to breed.

Today eucalyptus essential oil is distilled not only in Australia and Tasmania but also in Brazil, California, China, India, Portugal, Russia and Spain. Most eucalyptus species along with the oils they produce can be divided into three groups.

Medicinal and aromatherapy oils such as E. globulus and E. radiate. Industrial oils and Perfumery oils such as E. citriodora.

The primary active constituent in the medicinal/aromatherapy eucalyptus species is cineol, also known as eucalyptol. Cineol's medicinal; camphoraceous aroma has antiseptic and expectorant properties. The brisk aroma is energizing.

The species of eucalyptus oils that are used in industry contain constituents used in flotation, a process used mainly in the mining industry to separate ore particles from unwanted minerals. The eucalyptus oil most often used in perfumery is eucalyptus citriodora, the lemon scented eucalyptus. Lemon eucalyptus contains up to 90% citronellal along with geraniol. Both of these constituents are primary fragrant compounds in the perfume and cosmetics industry. Such a high percentage of citronellal in one botanical source makes its extraction very cost effective. .

All eucalyptus oils are produced through steam distillation of the fresh leaves and branch tips. The initial distillation yields darker yellow oil than most commercially available oil. This is because the crude oil is redistilled or rectified, to remove various less stable constituents that would cause the oil to deteriorate more rapidly. It also produces a more consistent product with the characteristic cineol constituent predominating. People familiar with the sweet, fresh-woody aroma of green eucalyptus leaves, are often confused by the more medicinal aroma of the oil. This difference is due to the chemical changes that naturally take place when heat is applied in distillation and redistillation. Also, some aroma constituents in the living plant are not a part of the essential oil. For those wishing to use a sweeter eucalyptus the lemon scented variety is a good alternative.

Aromatherapy applications rely on the activating, vitalizing and energizing actions the aroma of eucalyptus inspires. Activating eucalyptus massage oil is effective for sore and aching muscles.

Combine the following:

• 20 drops eucalyptus
• 20 drops lavender
• 5 drops peppermint
• 20 drops rosewood
• 5 drops wintergreen

• 30 drops bergamot
• 50 drops lemon
• 20 drops lemon eucalyptus