SA’s top ten from the National Register of Big Trees

It’s official – the experts have gone out on a limb and declared a 400-year-old giant in the Flinders Ranges is not just the state’s biggest tree.

Big and beautiful, great and grand trees can be found all over the state.

But there’s one that surpasses them all.

A river red gum known as Old Emu Foot in Melrose comes out on top in the National Register of Big Trees.

The property owner David McCallum, 69 of Gum View said the tree was believed to be 400 years old and held special significance for local Aboriginal people as a “shelter tree”.

“We have some other massive trees, but they’re not as big at the base,” he said. “Looking at it you might think there are other trees that are just as big, but they’re obviously not.”

Sydney man Derek McIntosh is the creator and curator of the National Register of Big Trees. Here he stands in front of a Bismark Palm, 15.8 metres tall. Picture: Brendan Radke

The register, established and maintained by Sydney tree enthusiast Derek McIntosh, uses a formula borrowed from American Forests that allocates a points total by adding trunk circumference in inches to height in feet and a quarter of the canopy spread, also in feet.

Mr McIntosh said the formula was developed for use in commercial forestry, with a focus on the amount of timber a tree yields.

“Clearly the circumference of a tree is the primary indicator of the timber volume in a tree,” he said.

“That is why the circumference is in inches, thereby resulting in many points, as opposed to it being in feet.”

With a solid base shaped like the big bird’s foot, Old Emu Foot is not only the biggest tree in the state under the formula, but also the biggest river red gum in Australia.

It has a circumference of 14.82m, height of 35m and crown of 29m, which when converted under the formula yields a points total of 722.

Old Emu Foot in Melrose is the biggest tree in South Australia on the National Register of Big Trees run by Derek McIntosh.

Old Emu Foot pictured with property owner Dave McCallum. Credit: District Council of Mount Remarkable

Tree 0179 on the National Register of Big Trees is a Moreton Bay fig (Ficus macrophylla) at Tintinara Winery, Main Road, McLaren Vale. Picture: Dean Nicolle

The two enormous Moreton Bay figs that come in at second and third place on the state’s top 10 list, at Glen Osmond and McLaren Vale respectively, have larger canopies but are not quite as tall.

Mr McIntosh started the register in May 2009 with just 18 trees “to promote the preservation of big trees as impressive examples of tree growth, natural beauty, valuable genetic resources, and inspiring symbols of conservation”.

Now there are 923 trees on it, including 82 in South Australia.

The biggest tree in Australia is a mountain ash known as Kermandie Queen in Geeveston, Tasmania, with a whopping score of 1069.

The National Trust is also expanding its own, separate significant tree register, which lists more than 1500 trees in SA including 18 of national significance.

In SA, the Trust is promoting a competition to find the SA Tree of the Year 2022. The competition is run by the Adelaide Facebook group 20 Metre Trees, led by Tom Morrison, Mitcham Council’s 2021 Young Citizen of the Year.

Winner of the inaugural South Australian Tree of the Year 2021 competition, a dingley dell gum (Eucalyptus leucoxylon subspecies megalocarpa) found in Port MacDonnell. Picture: Ockert Le Roux.

Last year the winner was a dingley dell gum at Port MacDonnell, described as “twisted and beautiful, especially in the mottled light of a setting sun”.

Nominations for this years’ competition close on Saturday (March 5). Then the top 24 trees will be selected by an expert panel. Public voting starts on March 9 with the winner to be announced on April 2.

Visit 20metretrees.org to nominate.