The Fire at Wallaby Creek

February the 7th, 2009. Black Saturday. 173 people were killed, over 2000 homes destroyed, and around 450 000 hectares of land was burnt as a result of the devastating bushfires that swept across Victoria that day.

As a result of the fires, around 100 000 hectares of bushland was burnt. This included the tallest trees on mainland Australia, a clump of Eucalyptus regnans (mountain ash), in a water catchment reserve north of Melbourne called Wallaby Creek.

Eucalyptus regnans are the largest of the Eucalyptus species. They are also the world’s tallest flowering plant, with some specimens growing over 80 meters in height. For an idea of the vast scale of the mighty mountain ash, below is an excerpt from ‘Forests of Australia’, by Alexander Rule (1967):

It is recorded that two expert axemen, working on a platform 15ft (5m) above the ground, took two and a half days to cut a scarf 6ft (2m) deep into the mighty butt as a preliminary to sending the giant toppling to earth. The crash of its fall resounded for miles around and even hardened bushworkers are said to have downed tools in silent homage to the fallen monarch. Its age was put at 400 years and it was calculated that when Abel Tasman discovered the island in 1642 this tree was already a noble specimen of between 150 and 200 ft (45-60m) in height.

Apparently the tree yielded nearly 2000 cubic meters of wood which was turned into 75 tons of newsprint. Newsprint?! Argh!

The mountain ash trees at Wallaby Creek were over 96 meters tall and around 300 years old. Gone. Overnight. 300 years of energy, habitat, and life turned to ash. These ancient giants were one of only three patches of old growth mountain ash forest left in Victoria, according to real-life plant hunter, Brett Misfud, who discovered them around 10 years ago. Two out of the three patches were burnt during the Black Saturday fires.

Many Eucalypts resprout readily after being burnt, however Eucalyptus regnans can be killed outright by severe fires. It relies solely on seed for regeneration and can be completely wiped out from an area if fires occur frequently. Misfud says that when a big fire strikes, the trees are usually killed but the heat of the fire dries the seed capsules in the crown of the tree and within a few days, millions of seeds fall to the forest floor and the next generation of trees will begin their journey.

It is hard for Misfud to go back. He says he is a celebrator of the living, rather than the dead. But he did return soon after the fire to check the regrowth of the forest.

I went back in after the fires to see what the regrowth was doing… There was one tree alive in June 2009 but not alive in 2010. Very few trees sprouted. It’s quite sad. If it was one of 30 patches of old trees and there were another 25 living it wouldn’t have been so sad, but it was one of three. And we have now lost two out of the three.

The forest has changed completely. It is now punctuated by vast, sculptural skeletons standing high above a sea of bright green saplings, all reaching up towards the sun. It is a competition. The tallest and the fastest will win. The canopy will close and the slow ones will miss the boat.

New plants are taking the place of the old at Wallaby Creek. But it’s a balancing act. Without another fire for around 25 years, the saplings will have enough time to mature and start producing seed, but if there is a fire? Well, thats that. The noble Eucalyptus regnans, tallest tree in Australia may no longer exist at Wallaby Creek.

The Black Saturday fires were caused by humans. And when humans are in the mix, anything is possible. Australian native plants have adapted over many thousands of years to cope with periodic burning practices by indigenous people. Understanding the regularity and intensity of fires required to stimulate a native ecosystem, rather than decimate it is a work in progress. And in the meantime, possibly as a result of human induced climate change, extreme fire events seem to be increasing. What this means for our valuable native bushland is unclear but its hard not to be concerned. Biodiversity, habitat, heritage. There’s plenty to lose and not quite as much to gain.

So, whilst we mourn the loss of the tallest trees on mainland Australia, and ponder the future of the saplings taking their place, we can also celebrate. We celebrate nature; for its resilience, opportunism and tenacity. We will be long gone but the trees will still be here.