The Octopus Tree on Mount Wellington is close-by this geocache. It is an easy 1km return walk detouring off the Shoobridge Track on Mount Wellington.
The Octopus Tree is a must see on Hobart’s Mt Wellington. It is an enormous Eucalyptus regnans that sits firmly atop a huge sandstone boulder, its roots bare and snaking over the side to the soil some 2-3 metres below.
This Eucalyptus regnans (also known as mountain ash, swamp gum, or stringy gum) looks to be walking. Its tentacle-like roots have emerged from the ground to wrap around a massive sandstone boulder and it seems to be tightening. You can almost imagine the tentacles contracting and releasing.
Eucalyptus regnans are straight and tall – incredibly tall – with massive girths. They are in every sense living giants. It’s given name is as the monarch of eucalypts; regnans being Latin for ruling or reigning. Its massive stature gave rise to the name.
It is possible that Eucalyptus regnans was the tallest living thing on Earth. They are certainly the world's tallest flowering plants. Many of the biggest were felled in the mid to late 1800s before they could be properly measured. Today they are second only in height to California’s Coast Redwood, Sequoia sempervirens.
Specimens of Eucalyptus regnans regularly exceed 85 metres in height. One tree in the past was measured at 132 metres tall. Today’s tallest is Centurion (discovered 2008, last measured 2018) at 100.5 metres tall. It is found in the Huon Valley in Southern Tasmania. Tasmania’s tallest building, the Wrest Point Tower at 73 metres is dwarfed by these trees. An introduced Eucalyptus regnans is New Zealand’s tallest tree. It grows in the South Island and was measured in 2012 at 80.5 metres tall.
These trees need huge and often deep root systems to supply adequate amounts of water. The Octopus Tree uniquely has much of its root system above ground on full display.
This tree’s thick roots grow around the rock like the tentacles of an octopus. You can walk all the way around the base of the tree, but the left side is the one that most resembles an octopus. Four large finger-like roots extend from the trunk and clutch the boulder below like fingers around a ball. How this now massive tree has come to sit atop this huge boulder is a genuine mystery.
Nearby is an octopus’s garden of ferns, fungi, and moss clinging to the roots and rock on that side of the tree.
The geocache is located around 10 metres to the north of the tree. This location is poor for GPS reception...so you may well need the hint.