“I study landscapes and given that gum trees are everywhere in Australia,
they're a huge part of what I look at. The types of gum trees,
the types of animals and plants that are with them, the types of fire they need. All of those sorts of things so we can develop ways to keep Country healthy.”
“Right, let’s go. We’ll walk through here.”
There are almost 900 species of gum trees in Australia.
And scientists like Associate Professor Michael-Shawn Fletcher, who is a geographer, and Dr Rachael Fowler, who is a botanist, study them for a variety of reasons.
“How do you identify eucalypts?”
“I look for the really distinct shape of a eucalypt leaf and then sometimes we can crush it
and smell the eucalyptus oil that most species have.
To tell the difference between different species, I look for the different size and shape of the leaves and the different colours and shapes and sizes of the fruit or the gumnuts.”
Eucalypts often grow higher than 10 metres, which is taller than a two-storey house.
They’re also home to many animals.
The koala, the ringtail possum and the greater glider eat eucalyptus leaves.
Birds and honey possums eat the nectar in flowers.
“How does studying gum trees help animals in the forest?”
“If you look around, all of the big trees here are gum trees.
Almost everything that's living in this forest is using gum trees somehow.
Insects eating leaves, bees in the flowers, birds eating the bugs, koalas eating the leaves.
So by studying the different types of gum trees, we can understand what food and shelter and other things are needed for all the animals in a forest.”
Like all living things, eucalypts have a life cycle.
A gum tree starts its life as a seed and grows into a mature tree and after about ten years, it flowers.
The flowers look like a coloured fluffy brush inside a cap.
They’re pollinated by wind, bees and birds and when fertilised, fruit develops.
On a eucalypt, the fruit is the woody capsule or gumnut which contains the seeds that are released and fall to the ground.
If conditions are right, the seed then germinates and grows into a seedling, then a taller sapling and then a tree.
“By combining ancient fossils and analysing DNA, scientists now believe that eucalypts are up to 70 million years old.”
And over the years, many eucalypts have evolved to enable them to live and even thrive in bushfires.
“Just about every aspect of a eucalypt is designed around fire.
Tough gumnuts to protect the seeds and allow seeds to be released into an open landscape.
Bark that's either thick that protects the tree, or strips off to produce lots of fuel.
Leaves that are jam packed full of oils and really flammable.
Their whole ecology is based around fire.”
“What do people use gum trees for?”
“Indigenous people, Aboriginal and Torres Strait Islander people, use gum trees for so many things,
to make boats, musical instruments, for bush medicine, for honey, and we use them today to make houses, wood for houses, to build furniture, to make paper.
All sorts of things. They’re very, very important trees for people.”
Gum trees serve many purposes and with about 150 species now highly endangered with loss of habitat, it’s important for all of us to protect them.
“Eucalypts are a part of our culture and part of our heritage.
They're a part of what it means to be Australian and it's important that we preserve
and conserve and protect eucalypts for future generations and for future use.”