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This is a tree. One of 164 Eucalypt species in Victoria. In this thread I will be describing the features of each one. 1/165
Actually, no. Just this one: Eucalyptus regnans. The bad boy of the Australian forest, as no one calls it.
Picture: http://www.nurseriesonline.com.au
Picture: http://www.nurseriesonline.com.au
Why this one? Well, it occurs primarily in the Central Highlands of Victoria. Other stands can be found in the Otways and Strzelecki Ranges, but primarily here.
Yes, I have heard of a place called Tasmania.
Yes, I have heard of a place called Tasmania.
Alas, it is also a species favoured for logging by those environmental vandals VicForests. There's a lot of wood in them thar trunks, and they grow mighty close together.
Picture: https://victoriasgianttrees.weebly.com/tall-trees.html
Picture: https://victoriasgianttrees.weebly.com/tall-trees.html
So this thread is largely in homage to these trees. What makes them special, and what their future might be.
As the species name (regnans = ruling) suggests, these are big trees. The tallest flowering plant in the world, no less.
Take that, slow growing, non flowering California Redwood!
Take that, slow growing, non flowering California Redwood!
Currently, Australia's tallest tree is this one, a regnans in Tasmania (huh).
Just above 100 metres tall. About 300 years old. And 200 metres from a logging coupe.
Picture: ABC news 12/12/18
Just above 100 metres tall. About 300 years old. And 200 metres from a logging coupe.
Picture: ABC news 12/12/18
But historically there have been bigger ones. A tree felled in 1880 near Thorpdale was measured at over 114 metres tall.
As happened back then, it was cut down with no thought to its beauty or value to future generations. They still are, in fact.
Pic: http://www.weekendnotes.com
As happened back then, it was cut down with no thought to its beauty or value to future generations. They still are, in fact.
Pic: http://www.weekendnotes.com
As you might guess, growing to that size (90 metres after hundreds of years) they need cool conditions and high rainfall. Frequent cloud cover at ground level is also necessary, which gives them a moody backdrop.
Fire is not a frequent visitor to these forests.
Fire is not a frequent visitor to these forests.
Mountain Ash do not reshoot epicormally after fire like other eucalypts.
But an intense fire will release seeds from the canopy. Newly fertilised by ash, and with more sunlight reaching it, the ground becomes a seedbed for this species.
Pic: victoriasgianttrees
But an intense fire will release seeds from the canopy. Newly fertilised by ash, and with more sunlight reaching it, the ground becomes a seedbed for this species.
Pic: victoriasgianttrees
Over time, these saplings will thin themselves out. With even more time, lower branches are lost and the forest giants will have returned.
After 120 years, cavities can appear and these provide nest sites for birds and animals.
After 120 years, cavities can appear and these provide nest sites for birds and animals.
Fire in an old growth forest will also produce 'a cohort of large dead trees and fire scarred living old trees that can provide nesting habitat for a suite of cavity-dependent species such as Leadbeaters' possum'. (Burns et al 2014).
They cannot sustain fires too close together. Less than 20-30 years and they will not have set seed. Acacia thickets can then become the dominant vegetation.
So, major fire every few hundred years would appear the norm, with falling trees allowing regeneration at other times.
So, major fire every few hundred years would appear the norm, with falling trees allowing regeneration at other times.
Enter VicForests. Whilst the CEO appeared to claim on Twitter it does not clearfell any more, it still does with Ash forests (which includes E. delegatensis).
It also 'salvage logs' burnt areas.
It also 'salvage logs' burnt areas.
Logging has the potential to replace all trees with even aged regrowth. Not only is this bad for habitat, it can lead to 'dense, young post-harvest regeneration that is at risk of re-burning at high severity'. (Burns et al.)
This is a positive feedback loop - which is bad news.
This is a positive feedback loop - which is bad news.
Fire and logging repeated in short rotation can stop Mountain Ash forest ever reaching the stage of old growth after 120 years. Instead it remains forever young. And not in good way.
To make this even more tragic, the Mountain Ash forests of the Central Highlands have been scientifically assessed as the most carbon dense in the world.
By cutting them down, we add to atmospheric carbon. Which is precisely what we should NOT be doing in a climate emergency.
By cutting them down, we add to atmospheric carbon. Which is precisely what we should NOT be doing in a climate emergency.
Even the Victorian government's own Scientific Advisory Committee (SAC) accepts the community could be vulnerable to the effects of climate change. Effects that logging by VicForests is mindlessly exacerbating.
The map below (from an ABC report from 2015) shows how much area of the Central Highlands was burnt in the 2009 fires, as well as how much has been logged.
The whole Central Highlands have been smashed around. And continue to be so.
The whole Central Highlands have been smashed around. And continue to be so.
So combine the interconnected factors of logging, climate change and an increased fire regime, and it's clearly bad news for our Mountain Ash forests and the species that live in them.
Cue cute shot of Leadbeaters' possum.
Photo: Zoos Victoria
Cue cute shot of Leadbeaters' possum.
Photo: Zoos Victoria
In 2014, the International Union for the Conservation of Nature (IUCN) placed the Mountain Ash forests of the Central Highlands on its Red List of Ecosystems.
This listing was based on a peer reviewed 2014 study by Australian academics (Burns et al). Using the Red List of Ecosystems criteria, it looked at the data and concluded a near certainty of ecosystem collapse by 2067.
But the SAC, when asked to list the Ash forests as endangered under the Flora and Fauna Guarantee Act 1988, did not come to the party (Its reasoning is available online: type Sac Mountain Ash into Google)
So don't assume these giants are here forever.
Pic: Wikimedia Patche99z
So don't assume these giants are here forever.
Pic: Wikimedia Patche99z
Dreaded footnotes
Emma Burns, David Lindenmayer, John Stein, Wade Blanchard, Lachlan McCartney, David Blair and Sam Banks (2014) Ecosystem assessment of mountain ash forest in the Central Highlands of Victoria, south-eastern Australia. Austral Ecology.
Emma Burns, David Lindenmayer, John Stein, Wade Blanchard, Lachlan McCartney, David Blair and Sam Banks (2014) Ecosystem assessment of mountain ash forest in the Central Highlands of Victoria, south-eastern Australia. Austral Ecology.
