Life and death is a part of evolution and is therefore inevitable, as the law of nature postulates.
But the death of thousands of trees of a particular species in Cooma-Monaro region of New South Wales, Australia, is far from natural.
A recent study published by Cris Brack, Associate Professor Forest measurement and management, and Catherine Ross, PhD candidate, both from Australian National University, reveal that a whole landscape of Eucalyptus viminalis, an Australian eucalyptus tree also known as Ribbon Gum or Manna Gum, has turned into a graveyard over a decade. The report mentions that the large stands of this tree, once considered to be a dominant one in Monaro, have been gradually declining in health.
The area under devastation
An article published in the Conversation quoted the researchers as saying, "We found the affected area to cover almost 2,000 square km, about the size of the area burnt in the devastating Ash Wednesday bushfires in Victoria or more than the area covered by the 2003 Canberra fires."
Every Ribbon Gum in this area has been found either completely dead or showing signs of severe illness or what is called a dieback.
All that can be seen around are clusters of dead branches resting over feeble trunks. One significant observation made is that other tree species in the vicinity seem to be surviving, as the smooth-barked gum with its characteristic ribbons of peeling park is decaying.
What is a dieback?
Dieback is not a new phenomenon for Australia. The first signs of rural dieback were observed in the New England area of New South Wales during the 1970s and 1980s. The reason behind this was established as agricultural practices such as grazing, fertilisation and understorey clearing (the cleaning of shrubs or unwanted vegetation) which hindered the balance of insects and their predators.
This led to a population explosion in insects thereby resulting in excessive loss of leaves and the recovering ability of the tree. In the case of the Monaro dieback, one of the causes of damage seems to be an infestation of the (native) Eucalyptus Weevil (Gonipterus sp.) or an insect that has been spotted on the other surviving trees in large numbers.
More than meets the eye
The study also says that the underlying reasons of the dieback are much more complex.
As per the observations made in the study, the Ribbon Gums appeared to be uniformly dead or showing signs of severe dieback regardless of their local environment.
Similarly, absence or presence of recent fire or pasture improvement makes no difference to the trees' health. Even the practise of fencing doesn't appear to be effective in saving the Ribbon Gum.
Is climate change the culprit?
One of the reasons which the researchers have also attributed the dieback to is the The Millennium drought which coincided with the onset of the dieback.
A popular theory rests on the harsh climate of the Monaro region. Over the years, the region has been experiencing extremes of temperature and very low rainfall.
The conclusion over which the researchers seem to be arriving is that the Ribbon Gums normally grow in wetter areas and the Monaro is at the edge of their climatic range. So, the death of the trees could be a severe consequence of the Millennium drought and ongoing climate change.
A larger concern
This might be happening in one corner of the world but raises a larger concern for all of us.
The rapid loss of vegetation, which ought to raise an alarm, has received relatively little attention or action globally.
The study suggests that the speed at which the dieback is occurring leaves other species little chance to adapt. There are negligible chances of recovery or any other species filling the gap.
According to researchers, Monaro stands as a frightening example for us to efficiently predict and prepare for other such events which have been reported across the world.
This is of course a crucial time when we dwell on our priorities in relation to the use and conservation of natural resources. While Monaro's Ribbon Gum is at loss, there might be other dominant species heading towards such a fate of which we might not even be aware. We still have time to act, an option we wouldn't be left with 100 years from now.