Saturday 26 July 2014

Impossible things that trees do

My city - Canberra - has been celebrating Tree Week in the lead up to National Tree Day on Sunday 27th July, 2014. I am not sure who decides on these national celebration dates, but I am happy that trees have their own day.

As part of Tree Week, I was invited to make a presentation during celebrations at the National Arboretum of Canberra, and thought I would let the trees themselves show off - demonstrating things they do using only the energy from the sunlight that falls on them that humans can only wonder at. I certainly had fun with that presentation, but I may have gone just a little far with my descriptions of the marvels of trees if the newspaper reports are anything to go by - awed gasps and impassioned sermons?! 


One of the examples I provided was about the (theoretical) ability of trees to grow almost as tall as the Black Mountain Tower (an icon in Canberra) while using only sunlight and simultaneously sequestering over 15000 t of CO2. Humans on the other hand needed over 350 t of reinforcing steel, 1930 t of concrete and emitted over 1700 t of CO2 to build their tower (admittedly in a much shorter time than my hypothetical tree!). While these boring numbers might not have generated awed gasps, the accompanying video footage certainly did -  you can feel both the height that the biggest currently standing trees can get to and see the Tower and its role in the city.

So, particularly on National Tree Day, don't just walk past a tree as if it is just a common ordinary sort of thing - it produces material that is stronger than steel, can pump water from 400 feet below the ground or to 400 feet above the ground, maintain hundreds or thousands of other living species in their crowns and roots, and make humans feel safer and healthier just by looking at them. They can do all these things with air, water and sunlight. Yeah trees! 




Wednesday 16 July 2014

The value of a plastic tree

"What is the value of a plastic tree?", was believe it or not, the name of a course I completed as part of my PhD studies in Northern America. They had this idea, very foreign to Australian universities, that there should be some philosophy in a Philosophy Doctorate. I was a little disappointed that the course did not cover too much in the way of trees, but we did explore the concept of value in depth. 

What is the value of a duplicate that is indistinguishable from an original? I imagine the artistic community struggles with this question when dealing with really good forgeries. In fact, I understand that some forgeries now may be more valuable that the originals because of the skill of the forger! Does the value of the copy depend on the value of the original; the fame of the person creating the copy; or amount of effort or training required to spot the "fake"?

In Australia, many forests are highly prized for their wilderness and old growth qualities. The recent World Heritage listing in Tasmania revolved around the wilderness, old growth and biodiversity values of the forest. Commentators were ecstatic in their appreciation of these magnificent forests which had been undisturbed by European colonisers and their descendants. These forests should obviously have great value. Now I am very happy to acknowledge that old growth and ancient forests have great value - even greater than the value of the Old Masters. But, the old growth and wilderness forests in this debate are fakes. 

One only has to have a little understanding of forest ecology and the opportunity to visit, before it becomes obvious that these forests had been commercially harvested and otherwise subject to extensive human impact. City-dwellers, who have been known to confuse commercial plantations of Pinus radiata with native forests may not quickly identify the fake, but the presence of stumps cut by axe or chainsaw and historic maps of extensive harvesting patterns, mean that very little effort would be needed to eventually spot the fake. So then, is the value due to the person/making the fake?

Those forests may have been able to "fake" being old growth, wilderness and biodiverse because the Foresters and loggers ensured their impacts resulted in adequate and appropriate regeneration. Not a trivial exercise, especially given the extremely different demands by the eucalypts (pioneer) and rainforest (successional) tree species in Tasmania. Many experts would have difficulty identifying the species and structural mixes caused by good forest silviculture and "natural" disturbance. But unfortunately in modern Australia, few people value the skill of these who can copy wilderness, old growth and biodiversity - enrolment of domestic students in professional Forestry programs continues to decline.

So, is it only the value of the original that counts, and any copy, no matter how poor and how easily distinguishable from the original, is valuable? Plantations then should be considered valuable for their old growth and wilderness contributions even as they have commercial value for the renewable products they produce. Maybe this is true in modern Australia - the National Arboretum of Canberra consists of about 100 "forests" of about 2 ha each, designed so that when standing in the middle of each forest all you can see is that forest. The architects envision that such a design will provide a feeling of peace, connection with nature and possibly even some "wilderness" value despite no natural (valuable) forest in the world ever looking these little 2 ha forests in Canberra. How many of the 1000 visitors / day to the National Arboretum will realise or even care that these forests are very poor mimics of "real" forests? How many will equate these fake forests with "real" forests, and does that result in a relative increase in the value of the fake or a decrease in the value of the original? 



Are any of the "forests" or landscapes in the attendant collage valuable? They are all elaborate fakes developed over 5 - 100 years from land cleared or degraded due to mining and grazing. What makes these fakes valuable ...and which is most valuable?

Why did that philosophy course only train me in asking questions about the value of a fake forest?