Not long ago, gentle reader, a good friend of long standing took me out for dinner;
Before dinner I noticed that the brand of tonic water which came with my gin was Fever-tree.
And suddenly there came into my mind words from Rudyard Kipling’s story of the Elephant Child in his wonderful book The Just-so Stories. And I remembered that the elephant’s child “went from Graham’s Town to Kimberley, and from Kimberley to Khama’s Country, and from Khama’s Country he went east by north, eating melons all the time, till at last he came to the banks of the great grey-green, greasy Limpopo River, all set about with fever-trees.”
A trademarked name for a brand of soft drinks and a well-remembered … but perhaps imaginary … name of a tree from my childhood – but does the fever tree really exist and how did it come by that strange name? Well, to begin at the beginning, there is a Limpopo River. It rises in central southern Africa and flows generally eastwards, becoming the second largest river in Africa … after the Zambezi … to drain into the Indian Ocean. And yes, its banks are set about with fever trees in places, for the fever tree grows, among other locations, in low-lying swampy areas, along the margins of lakes and on river banks. Its botanical name is Acacia xanthophloea … Acacia from the Greek word ‘akis’ meaning ‘a thorn’ and xanthophloea from two other Greek words meaning ‘yellow bark’. Many of the first Europeans to venture into areas where Acacia xanthophloea grows contracted a bad fever and blamed the ‘fever tree’ for causing it. Later arrivals realised that the fever was malaria, actually spread by the mosquitos which thrive in the swampy places favoured by the tree.
The fever tree … which has retained its original common name … is an attractive, tree with greenish-yellow bark and long straight white thorns which are very significant on young trees but barely noticeable on mature specimens. It grows to a height of between 15m and 25m … say, 50 ft. to 80ft. in old money. Between late August and early November it carries bright golden-yellow, ball-like flowers with a sweet scent, which develop into yellowish-brown seed pods containing small, hard, brown seeds. Fever trees are fast-growing and short-lived and are favoured by nesting birds, for the thorns offer added protection against snakes. Elephants, giraffes and monkeys feed on the leaves and seed-pods. Medicinally, the bark was used by the indigenous peoples of what was known as Khama’s Country in Kipling’s time and is called Botswana today in the treatment of fevers … a curious coincidence … and eye complaints.
Acacia xanthophloea is a pretty tree, often used to decorate gardens and urban landscapes in South Africa. Its attractive bark, feathery foliage and architectural appearance make it an excellent choice as a focal point in a landscape. It grows quickly and in just two or three years its canopy will provide dappled shade in which smaller plants can shelter from the fiercest sunlight. It is simple to propagate from seed … and this characteristic can be as much a drawback as it is a virtue. The fever tree has been introduced into parts of Australia, where the Department of Employment, Economic Development and Innovation in Brisbane warns that, “Acacia xanthophloea shares several biological attributes with one of Queensland’s worst weeds of grazing land, Acacia nilotica. As such, it seems reasonable to predict that Acacia xanthophloea could become a significant weed of grazing land and riparian habitats in semi-arid and arid parts of Queensland if it escapes cultivation and is allowed to spread.” As with many exotic plants, the enthusiastic gardener can buy seed in the UK. But, while I would not expect Acacia xanthophloea to grow here, please don’t even try, just in case!