September 1 has many names. Some welcome it as spring's dawn, a time to celebrate nature's renewal. For others it is Wattle Day. It is a time when the smells of spring are in the air and the vivid gold of the blossom is literally arresting. But it will never be Racosperma Day. At the International Botanical Congress in Melbourne in July 2011, one longstanding debate, “Who gets the Acacia?” finally got closure, writes history editor Dr Glenn Davies.
For hundreds of years, since Swedish botanist Carl Linnaeus first described the type species of the genus Acacia in Africa in 1773, both the African and Australian continents could lay claim to acacia trees. But in the past 30 years, anatomical and genetic analyses demonstrated that Australian and African acacias do not belong in the same genus at all. To two different continents, the Acacia is more than just a tree — it's an icon. The flat-topped thorn trees silhouetted against a red African sky and the golden wattle of Australia whose green and gold colours inspire the garb of the country's Olympic athletes. So which trees – Australian or African – should be known as actual Acacia?
The problem was that the original acacia was an African plant, described 17 years before Cook reached Botany Bay. Strictly speaking, some claimed, Australia's wattles should be renamed racosperma. But several Australian botanists argued that since the large majority of the world's acacias - about 960 of the 1350 known species - were Australian natives, the name should stay here. Essentially Africa had prior claim since the first type species, Acacia nilotica, was found there, but Australia has the overwhelming majority of species.
In Australia, the wattles are the largest genus of flowering plants. In Australia you could plant two or three different wattles for every day of the year, and still have plenty left over, for Australia has more acacia species than the year has days. These acacias are extremely diverse and found in habitats from rainforest to arid lands. Botanists still ponder the question as to why there are so many different species of wattle in Australia. Why in Australia is there such wattle diversity? Given the iconic status of acacias both in Australia and in Africa it was inevitable that there was going to be controversy.
Australians may have made a home for themselves amongst the gumtrees, but it is the wattle tree that has found its way into Australian symbolism. Most Australians can recognise a wattle, at least when it is in flower. The Golden Wattle (Acacia pycnantha) is now the official floral emblem of Australia, wattle blossoms are to be found on the Australian Coat of Arms, and the Order of Australia is in the shape of a single wattle blossom. Australian Olympic athletes wear wattle inspired green and gold uniforms. A Governor General, Sir William Deane, took wattle blossoms to Switzerland to commemorate young Australians who died there and Prime Minister John Howard wore sprigs of wattle at ceremonies after the Bali bombings.
All these nomenclature issues came to a head at the 2005 International Botanical Congress in Vienna when the vote was put as to what plants could carry the name acacia. The simple question of what’s in a name divided the usually unified global group. Essentially the world's botanists were at odds over changing the rules so that the name acacia would apply only to Australia's 1000-plus species, meaning a smaller number of species, mainly from Africa, would have to change their name to vachellia. The alternative was to rename Australia's acacias, including the wattle, racosperma. Although the issue was seemingly resolved when the delegates decided that the acacia would belong to Australia the debate continued for another six years.
On 30 July 2011 the International Botanical Congress met in Melbourne where they formally declared that the genus Acacia – or wattle – is distinctly Australian and will remain so. The "Acacia Issue" — one of the most contested botanical cases debated to date — was resolved with the Congress upholding the 2005 decision. The vote concluded a long-running botanical battle to save the word acacia for hundreds of Australia's wattles, including the national floral emblem. While the Australian acacias retain the name, a new name is needed for the African and American species.
Wattle captures something crucial to Australia’s identity – a feeling for country and a spirit of place. The resolution of the “Acacia Issue” confirms the place of wattle in Australia’s dreaming.