Magic amidst a multitude of stems

Victoria's box-ironbark forests are magic. Whatever time of year you visit, their beauty is evident. The rugged, gnarled trunks of the ironbarks stand black as if they’ve clung to their night-time colour scheme despite the breaking of day. Up close, the black bark is crisscrossed by deep fissures, forming a net whose depths are the colour of rich amber and give the sense that the trees are bursting with warmth. The box trees are more demure. From the pale grey, elephant skin-like bark of the Grey Box to the shaggy mess of bark cloaking a Red Stringybark, each adds its own immutable stamp on the box-ironbark forest identity. Above, the foliage hangs grey-green as if a thick mist has descended on the forest. The calls of woodland birds ring out, and, at certain times of the year, the forest floor and understory is awash with floral splendour. There is no choice but to be spellbound.

The different bark characteristics of the dominant eucalypts (left to right: Red Ironbark, Grey Box, and Red Stringybark) give the box-ironbark forests an unmistakeable character. Image: Rowan Mott

The different bark characteristics of the dominant eucalypts (left to right: Red Ironbark, Grey Box, and Red Stringybark) give the box-ironbark forests an unmistakeable character. Image: Rowan Mott

When gold was found in central Victoria in the middle of the 1800s, miners soon flocked to box-ironbark country. They, like me, quickly saw how special these forests are. However, the value they saw was in the versatility of the timber. It made for ideal stays to bolster mine shafts deep underground; it was perfectly suited for use as railway sleepers in the burgeoning rail network freighting gold across the state. And, as hinted by the warm colour in the fissures of the bark, it burned with a long and lovely heat in campfires and cooking stoves. The rapidly growing population also increased demand for food and many of the grassy box-ironbark woodlands on fertile soils were soon replaced by agricultural enterprises to supply this demand. In the years that followed the discovery of gold, mining boomed and the magnificent box-ironbark forests were felled. 

Miners quickly descended on (and under) Victoria’s box-ironbark country during the middle of the 1800s following the discovery of gold. Evidence of their activity can still be readily seen today. Image: Rowan Mott

Miners quickly descended on (and under) Victoria’s box-ironbark country during the middle of the 1800s following the discovery of gold. Evidence of their activity can still be readily seen today. Image: Rowan Mott

I started this article by spruiking the magic of today's box-ironbark forests, and they are indeed magical. The box-ironbark forests we are fortunate to have today rekindled themselves from ruin like a magical phoenix rising from the ashes - a small, irrevocably damaged phoenix. When the gold rush began to ebb, disused mine sites began to regain their tree cover. However, box-ironbark forests never returned to their full extent. In fact, only 17% of their former area is forest today. Unlike the gold mining boom, agriculture and settlements have relinquished little of their hold over box-ironbark country with the passing of time. 

In parallel with the huge reduction in forest, a quick walk through one of Victoria’s box-ironbark forests today reveals other, more subtle legacies left by the gold rush. Most of the trees now standing have regrown from the base of the cut stump of their predecessor, and this regrowth has resulted in a forest made up of trees with multiple, thin stems. Gone are the immense forest giants of previous centuries, and their loss has seen the depletion of many habitat features relied upon by the wildlife that calls these forests home.

Many of the trees in today’s box-ironbark forests have re-grown from the base of a cut stump. This typically results in a multi-stemmed growth form. Image: Rowan Mott

Many of the trees in today’s box-ironbark forests have re-grown from the base of a cut stump. This typically results in a multi-stemmed growth form. Image: Rowan Mott

Tree hollows used by large birds and arboreal mammals are now scarce, and nectar – a key food source for many birds in these forests – formerly produced in copious quantities by the forest giants is now supplied in inferior volumes by their multi-stemmed counterparts. Furthermore, the larger trees would have produced more and larger fallen timber than today’s smaller trees, and thus species that use fallen timber for den sites (e.g. the Yellow-footed Antechinus) and foraging (e.g. the Hooded Robin) likely suffer as a result.

Species that depend on large tree hollows, such as the Barking Owl, are threatened by the lack of large trees in present day box-ironbark forests. The thin, multi-stemmed growth form of most of the trees simply cannot provide enough of this vital habitat feature. Image: Rowan Mott

Species that depend on large tree hollows, such as the Barking Owl, are threatened by the lack of large trees in present day box-ironbark forests. The thin, multi-stemmed growth form of most of the trees simply cannot provide enough of this vital habitat feature. Image: Rowan Mott

Species that forage on the ground among fallen timber, such as the Hooded Robin, are declining in Victoria. The loss of large, old trees, which contribute disproportionally to the amount of fallen timber, is likely a contributing factor in their decline. Image: Rowan Mott

Species that forage on the ground among fallen timber, such as the Hooded Robin, are declining in Victoria. The loss of large, old trees, which contribute disproportionally to the amount of fallen timber, is likely a contributing factor in their decline. Image: Rowan Mott

As time passes, it is possible to see the slow succession as the forest crawls towards its former glory. Tree stems growing from the base of a dead and decaying stump are often weak, and it is not uncommon to see one or more stems of a multi-stemmed tree lying on the forest floor, having split from the stump. Similarly, the dead stump lacks bark, which usually provides the tree with a protective shield from fire. Fire in a box-ironbark forest, even a low intensity fuel reduction burn, will often result in many multi-stemmed trees collapsing because they are burnt out from the base once fire enters the exposed stump.

And so, as the number of stems slowly decreases, the growth rate of those that remain increases because they no longer experience as much competition for resources, such as light, nutrients and water. The transition of our box-ironbark forests to their original state is glacially slow, but I am hopeful that one day these forests will once again be dominated by trees of a behemoth size.

It is not uncommon to see one or more stems lying on the ground after their weak attachment to the stump from which they were regenerating gives way. Image: Rowan Mott

It is not uncommon to see one or more stems lying on the ground after their weak attachment to the stump from which they were regenerating gives way. Image: Rowan Mott

Fire can more easily burn a dead and decaying stump than a live, bark-covered tree. Trees that have resprouted from the base of a cut stump are often more susceptible to fire than free-standing trees because they are readily burnt out at the base. Image: Rowan Mott

Fire can more easily burn a dead and decaying stump than a live, bark-covered tree. Trees that have resprouted from the base of a cut stump are often more susceptible to fire than free-standing trees because they are readily burnt out at the base. Image: Rowan Mott

If you were to take a large diamond and hit it with an even larger hammer until the diamond shattered into many tiny fragments, would you then throw the diamond fragments away? Of course you wouldn’t; they’re still diamonds after all! Victoria’s box-ironbark forests have been shattered by the hammer of the gold rush and agriculture, but they remain incredibly valuable. Their worth cannot be understated for declining species such as the Squirrel Glider, Woodland Blind Snake and Regent Honeyeater, for which box-ironbark forests represent their core habitat. Far from diminishing the magic of box-ironbark forests, their history of degradation in the last two centuries and the resilience they have shown is even more reason to celebrate them. 


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Rowan Mott

Rowan is a Monash University PhD graduate and now works there as an ecologist. His research interests are broad, spanning seabird foraging ecology to plant invasions. When not in his office, he will most likely be in a woodland with binoculars around his neck and camera in hand.

You can find him on Twitter at @roamingmoth


Banner image courtesy of Rowan Mott.