People in a field among the Acacia Tree Of Trees display.

The Acacia Tree Of Trees blossoms into life

The Acacia Tree of Trees provides a unique, interactive display of Australia's floral emblem, the Wattle, to show how each species of Acacia is related to other wattles.

  • 10 September 2010 | Updated 14 October 2011

Ongoing research into the taxonomy of Acacias aims to understand the diverse evolutionary biology behind one of the world's most abundant tree species. 

Acacias are found throughout Australia with over 1000 known species.

Acacias have an enormous diversity of floral, leaf and plant forms.

Researchers at the Centre for Australian National Biodiversity Research (CANBR)* are using the latest in DNA research and modern taxonomic tools to uncover the origins of Acacias. 

Acacias have an enormous diversity of floral, leaf and plant forms, and this diversity has been difficult to classify. 

The DNA work helps clarify which leaf characteristics are important to the taxonomy.   

The work traces biogeographic trends within the genus as some closely related species may grow in one part of the country while their close relatives are in another part of the continent. 

This poses challenging questions as to how the different Acacia species have evolved to occupy specific niches across the continents. 

As part of the Australian National Botanic Garden's 40th anniversary celebrations, the CANBR team, led by Dr Joe Miller, has created an amazing and unique display of Acacias in the form of a 'phylogenetic' tree. 

In this format, individual species are grouped at the end of 'branched' pine-bark pathways to denote how closely related they are to one another. 

The branching out of the 'tree' indicates splits in evolution of Acacias. 

A distinct split occurred early in the evolution of the species which now divides them into phyllodinous (phyllodes are broad flat 'leaves') species versus binpinnate ('feathery-leaved') types, many of the latter being common to the Australian Capital Territory.

While the Acacia research is ongoing, the Acacia Tree of Trees Display will be extended into an interactive page on the Atlas Of Living Australia (ALA) site, allowing users to 'virtually' walk through the branched pathways of the tree. 

Read other articles from the CSIRO Plant Industry newsletter.

*The Centre for Australian National Biodiversity Research is a joint venture between CSIRO and the Department of Environment, Water, Heritage and the Arts. The Centre houses the Australian National Herbarium, which is a research collection of Australian flora.