by Piter Kehoma Boll
There’s little as typical of the Australian vegetation as an eucalyptus tree. About 3/4 of all Australian forests are eucalyptus forests, and there are many different species in this small continent, many of which have a very restricted distribution. One species, however, is naturally found across the whole continent: Eucalyptus camaldulensis, commonly known as the river red gum.
Being the eucalyptus species with the widest distribution, the river red gum is found growing along watercourses of the continent. It has a typical eucalyptus look, with a smooth and white or cream-colored bark with some darker marks in yellow, pink and brown and dull green, lanceolate leaves. The tree reaches a height of about 20 meters, although some specimens be as tall as 45 meters. The flowers are white and open in summer, and the fruits are woody capsules as in most eucalyptus species.
Due to its wide distribution and association with watercourses, the river red gum is a very important species in Australian ecosystems. In dryer areas of Australia, the trees growing close to the water are the only available habitat for many species. When the trees fall into the water, their trunks also provide essential habitats for many fishes. After reaching 120 years of age or more, the trunk starts to have hollows, creating even more habitat for other species, such as bats, birds and snakes.
Like many other eucalyptus species, the river red gum was introduced worldwide for timber production due to its rapid growth. Its wood as a bright red color, hence the common name, although the color can vary from light pink to almost black depending on age and weathering. Other uses include firewood, production of charcoal and as nectar source for bees during the flowering season. Being highly adaptable and able to reproduce quickly, it became an invasive species in many places in all continents.
The study of essential oils of the river red gum revealed several interesting applications. Some compunds have good antibacterial activities and can be used for the development of antiseptic or disinfectant agents. Other compounds proved to be excellent mosquito repellents.
A hero in the australian ecosystems, the river red gum was turned into a vilain everywhere else by our human need to take everything with us.
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Ghalem BR, Mohamed B (2008) Antibacterial activity of leaf essential oils of Eucalyptus globulus and Eucalyptus camaldulensis. African Journal of Pharmacy and Pharmacology 2(10): 211–215.
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Wikipedia. Eucalyptus camaldulensis. Available at < https://en.wikipedia.org/wiki/Eucalyptus_camaldulensis >. Access on 20 October 2019.
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