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The E. regnans is the tallest hardwood tree in the world. It is native to Australia and found mostly in Tasmania and Victoria. It can be found in Tasmania's southwest, Victoria's Otway Ranges, Yarra Ranges and Alpine regions. This tree can grow for over 400 years and has been known to reach heights in excess of 130 metres (which would make it the tallest tree in the world!), although the tallest specimen known to exist today is a mere 96.5 m tall. The tallest of these giants are found in Tasmania's Styx river valley. |
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The forests in the Styx River valley are on land controlled by Forestry Tasmania. Forestry Tasmania grants licences to logging companies to "harvest" the trees. This is done through clear felling. In the Styx valley an area of 1000 hectares is reserved for the benefit of some of these giant trees. The rest of the valley, over 22,000 hectares, is subject to logging and replanting with both hardwoods and pine plantations. Most of the timber that is felled is chipped and sold to Japan. Since August 2000 the Forestry Tasmania has imposed a "rule" that E. regnans taller than 85 m high should be spared from the harvest. This is an attempt to appease environmentalists who are campaigning for a National Park to be declared in the valley. |
Person standing beside an E. regnans (under fern tree).
92 metres high. 15 metres girth (at one metre). |
The problem with such a policy is twofold. First, the saving of individual trees, or even trees surrounded by a mere hectare of forest, exposes the giants to increased winds due to the removal of the buffering forest that once surrounded them. Due to the great height of these trees, they tend to stick out above the median canopy and collect the full force of the wind. When the wind speed is not reduced or deflected by other trees in the area, the force of the wind has the capacity to shear the tops off these tall trees. The trunk bends under the stress and snaps. The tallest trees are often over 300 years old, and the inside of their trunks can be hollow because the wood inside rots over time. This makes the tallest of these giants susceptible to damage when their surrounding forest is removed.
Three trees can lay claim to being the tallest trees in the world, the Douglas fir (Pseudotsuga menziesii) that grows in the Pacific Northwest, the coast redwood (Sequoia sempervirens) of coastal California and Oregon, and a eucalyptus from Australia (Eucalyptus regnans). The tallest living tree is a coast redwood measured at 367 feet. The tallest Douglas fir is 329 feet, but there is good historical evidence that they reached 393 feet or higher. The tallest Eucalyptus regnans has been measured at 326 feet tall, but there is historical evidence that suggests they reached 400 and perhaps 500 feet in the recent past.
Secondly, the policy of removing all E. regnans which are less than 85 m high means that for so long as the forests are clear felled, all E. regnans less than 85 m will be destroyed. Trees 80 m high will be turned into woodchips. Trees 70 m high will be chopped, as will those 60 and 50 metres high. In time, the trees over 85 metres will die a natural death. If this policy remains in place for 100 years, you will see no new trees added to the small collection of trees that are over 85 m. The number of tall trees will gradually decline through natural attrition until there are no longer any trees over 85 metres high. Then will Forestry Tasmania review its policy to protect all trees over, say 55 metres, if it can find any?
A futher effect of adopting a policy like this is that it has an adverse affect on the evolution of the species. The oldest E regnans are often the tallest. They are often the strongest or hardiest. It is not correct to assume that any E regnans have the genetic capacity to grow to 100 metres. If that were so, there would be 100 metre tall regnans everywhere. The genetic capacity probably exists in the genes of those trees that succeed in reaching 90+ metres. Just like there are tall people and short people, it is the genes of the individual that help determine its growing ability. But it requires more than just genetic capacity to grow to 100 metres. The tree needs particular environmental factors. Some of these are obvious, like the right soil, water and climate. But even if we could reproduce a perfect climatic environment for the trees to achieve their best growth, this will not necessarily produce giant regnans. It is the competition of the forest that pushes these trees to grow so high. The "survival of the fittest" theory demonstrates what is causing these trees to grow until their crowns stare out over the forest canopy.
E. regnans is genetically programmed to grow until it reaches the top of its forest. It grows, or tries to grow, until its crown is no longer shadowed by other trees. If the other trees are less than 60 metres high, then regnans do not need to grow beyond 80 metres in order to achieve their goal. If the median forest canopy is at a height of 75 metres, then you will be more likely to find regnans pushing beyond 85 metres, because that is how high they will need to grow in order to be above the canopy. Removing the shorter trees reduces the amount of comptetion required to produce the tall trees.
Logging has the effect of reducing the median canopy height to something less than 50 metres. In this situation, it will be unusual to find any E. regnans pushing past 85 metres. The coups are harvested more often than once every 50 years, which makes it nearly impossible for any E regnans to grow to a height of 85 metres in such a short time.
The forests will stop producing giant trees unless the forests are protected in a much greater way than they are at present. Unless the regnans get competition from other trees, they will not grow so tall. A regnans in a low height forest will never reach 85 metres, just as a regnans seedling in a potted tub will never grow more than 10 metres. More needs to be done to promote eco-tourism in the Styx valley and other places in Tasmania where the regnans grows. Greater tourism and consequent economic benefits will flow if these giant trees are encouraged to reach their full potential at 100 metres plus. More needs to be done than simply preserve a few examples of the species and say "these used to be the tallest trees in the world". If you had a field full of apple trees, but felled each tree as it reached 1 metre tall, and replaced it with a seedling, you might have a large collection of the species, but sadly your examples won't show any apples.
In 1999 - 2000 Tasmania produced 5.1 million tons of woodchips, up from 3.9 million tons the previous year. That is more woodchips than the rest of Australian states put together. Some people say that thousands of people in the logging and timber industries rely on these forests for their jobs. The fact that some people are presently employed in logging is no surprise, and hardly a justification for maintaining the current practices. Similarly, poppy growers in Afghanistan are being told to stop growing a lucritive crop which brings in substantial economic benefits; whalers were told to stop hunting whales. Our society can not afford to let the fact that some people currently make a profit from certain destructive and anti-social activities to be the basis for allowing those activities to continue. Many people make money from the production and sale of tobacco products, yet people universally agree that society would be better off without any tobacco products at all. For so long as the government allows people to be employed in these destructive activities, the economic arguments will remain. Similarly, the housing/construction industry uses economic arguments to justify the common practice of carpeting our countryside with residential sub-divisions. People with self-interests in property development call for population increases to maintain demand for more houses on the basis that the economic wellbeing of the country will be in peril without it. The number of new home approvals is used as a measuring stick of economic health!! It sounds like the building of houses is an end in itself. If we stopped building houses on new sub-divisions, think of all of the resources and money we would save. And the loss of jobs? Well, even in the unlikley event that some people can't find work that is of beneift to the community, it is about time that the preservation of jobs ceased being a factor in environmental decision making.
We should look at the cost to the community as a whole of environmental destruction and weigh it up against the benefit of forest products to our community as a whole (and not just the self-interests of the shareholders in Gunns Ltd). Whether jobs are lost or created as a result of an environmental protection decision should have little relevance. There are always other jobs. There are no other Styx valleys. There are other ways to obtain materials to make paper. Logging old-growths is not necessary. The forest industry will say that the money that is made by several hundred forest workers, truck drivers and wood shippers justifies the destruction of an entire eco-system. The claim that many timber workers will never be able to find any other job is said to justify the destruction of the environment, but all it does is illustrate that the destruction of natures' forests is being done for the benefit of so few individuals that it is blindingly obvious that even if the benefits of old growth logging for selected individuals outweighs the costs of eco-system destruction, it can not be shown that the meagre benefits to the community outweigh these costs.
Destroying our forests to be sold as woodchips is such a short term view. It is like the whalers of the 19th century who thought the supply was never ending, and who thought only about their own financial gains. Likewise, building houses on new subdivisions does not make our country richer or better. On the contrary, it leads to a reduction in our standard of living. It does not help the natural environment or improve our standard of living. It causes pollution and a large drain on public monies spent building infrastructure. The line has to be drawn somewhere. The human species is not in danger of extinction, and our planet has never suffered from a shortage of humans. There is no need to increase the number of people in this country at the cost of the native landscape. Australia has coped quite well for over 200 years with less than 20 million people. I am sure we can survive another 200 years without increasing the population any further. Most other countries in the world are suffering enourmous problems due to the pressure of increased human population. Why does Australia try to emulate the over-populated countries? It is time we gave some thought to consolidating our gains, preserving the natural assets we currently have and using our workforce more intelligently to add value to our country instead of maintaining destructive practices. As population increases so does the world's appetite for wood products such as paper. Unless a balance is achieved soon, an increasing population will find that the decreasing old-growth forests have disappeared and been replaced with plantations, sheep, deserts or townhouses.
More Regnans Sites:
Forestry Tasmania - 10 tallest trees
Regnans species info.
Other links:
Wilderness Society - Styx Valley
31 January 2002
(Photographs courtesy of Wilderness Society).