The world's leading eucalyptus expert, Professor Steve Hopper, on what science and culture say about these spectacular trees, and how Noongar elders in WA's South West led his 'second education' in botany.

Australia is one of the richest places on earth when it comes to botanical biodiversity.

Tens of thousands of species of trees and flowers have developed over millions of years of isolation.

But perhaps the most iconic of all native flora is the humble eucalyptus.

From Queensland's ancient rainforests and the alpine region of New South Wales, to the wilds of Tasmania and the granite outcrops of coastal Western Australia, gum trees are synonymous with the Australian landscape.

There are 900 different species of eucalyptus, from giant gums close to 100 metres tall, to tiny wee mallee trees the same height as a kindergartener. 

Steve Hopper has recorded more than 100 of those species, and believes there are still more waiting to be found.

This episode of Conversations was produced by Meggie Morris, Executive Producer is Nicola Harrison.

It explores botany, climate change, extinction rates, gum trees, eucalypts, California wild fires, biodiversity hotspot, Australia's native flora, koalas, mallee, jarrah, karri, ancient trees, dinosaurs, Australiana, Western Australia, Great Southern Blue Mountains, Tasmania, South West of WA, Albany, Stirling Range, Snowy Mountains, red gum, stringy gum, Australian wildflowers, Kew Gardens, London, the United Kingdom, Joseph Banks, environmental exploitation, Indigenous knowledge, Indigenous healing, eucalyptus oil medicinal properties, dreaming, conservation, gardening.

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