Gold does grow on trees, Grandpa

The adage ‘Money doesn’t grow on trees’ may not be as true as our austere forebears wanted us to think, after all, since scientists have struck gold on the leaves of Australian eucalypts.

Eucalyptus trees in the Kalgoorlie region of Western Australia have been found to be drawing up gold particles from the earth via their root systems and depositing it on their leaves and branches.

Scientists from CSIRO made the discovery using advanced x-ray imaging and have published their findings in the journal Nature Communications.

CSIRO geochemist Dr Mel Lintern explained that the eucalypt acts as a hydraulic pump – its roots extend tens of metres into the ground and draw up water containing the gold.

“As the gold is likely to be toxic to the plant, it’s moved to the leaves and branches where it can be released or shed to the ground", Dr Lintern said.

The discovery is unlikely to start an old-time gold rush, however, since the "nuggets" are microscopic, about one-fifth the diameter of a human hair.

But it could mean that future exploration for gold or other minerals such as copper and zinc need not be so costly or detrimental to the environment since the trees give a clear picture of what lies beneath.