From what I just looked at it says they are referring to sports. -Green and gold is also represented on the Coat of Arms by the Wattle which is an ornamental accessory to the shield (the Wattle does not form part of the Armorial Bearings). I don't know if that's the answer you were looking for.
The Australian green and gold are the country's national colors. In the early 18th century, these were the colors that were used to represent the Australian sports teams internationally. The colors were chosen because they represent the Golden Wattle tree.