IT IS rare that controversy strikes the botanical world. But six years ago, when the International Botanical Congress met in Vienna to vote on 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 — which for some was too problematic to even contemplate — was to rename Australia's acacias, including the wattle, racosperma.
"Given the iconic status of acacias both in Australia and in Africa it was probably inevitable that there was going to be this controversy," said Bill Aitchison, leader of the acacia study group section of the Australian Plants Society.
While the wattle is Australia's botanical emblem and informs our national colours, the silhouette of the flat-topped thorn tree against a rust-red sunset is symbolic of Africa. Both, botanically speaking, are acacias. Until now.
The International Botanical Congress meets in Melbourne from today and it is anticipated that "the acacia issue" — one of the most contested botanical cases debated to date — will finally be resolved. During last week's nomenclature session, the 2005 Vienna decision was unsuccessfully challenged. This suggests that come this Friday, a final vote in favour of Australia using the name acacia is expected to be little more than a formality. Meanwhile, 163 species formally classed as acacia will now be known as vachellia.
The director of the Western Australian Herbarium, Kevin Thiele, said it was important that the nomenclature session vote to limit the name acacia to Australian species was soundly passed, with 68 per cent for and 32 per cent against.
A proposal to compromise by adding a prefix to the name acacia — so austroacacia would refer to Australian acacias and acanthacacia to species in Africa, India, the Middle East, South and Central America — was rejected by 70 per cent of voters.
The definitive results here are in contrast with those of Vienna six years ago, which has fuelled much of the ongoing contention.
At the Vienna congress most — 55 per cent — were in favour of allowing African species to remain acacias. The rules state that a 60 per cent majority is required, but there has been ongoing argument that a simple majority should have prevailed. "There is a lot of sympathy for those parts of the world that are losing the word acacia," Dr Thiele said.
"Africa is the home of the acacia, in that it is where the first acacia species was described. But Australia is the hot spot for acacia because there are over 1000 species here — none of which were known at the time the acacia was first described. So you can see why it's been so controversial."
Acacias are the most prolific genus of plants in Australia, with more than 1000 different species including the wattle. About 80 African species once called acacia would be renamed vachellia.
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