@VK3AUU: Maaate, can't you get into your head that old growth forests ultimately die.

That is an over generalisation. Some do, like the SA, VIC fire belt. Some don't, like the Amazon and Tasi's forests. (Every been there? It is a very wet place. Or at least it was. The locals were saying climate was drying out when I was last there, particularly in the western side of the island.)

@@VK3AUU: Mark Poynter knows more about conservation of native forests than you and your cohorts ever will.

I presume Poynter knows at lot about sustainable commercial exploitation of native forests. You are equating "sustainable commercial exploitation" with "conservation", which is just rubbish, or at best spin.

@leiverde: Accordingly, an old growth forest may hold less carbon than a younger forest.

That sentence and what proceeded it made no sense to me. The evolution of a piece of land starts as barren ground, absorbs carbon until it reaches a steady state and then I presume stops. However the carbon it contains remains locked up. Cutting it down releases it.

@leiverde: Clearfelling of forests does not result in a 100% emission of carbon as many of the products that are produced (inlcuding paper) are durable and survive for extended periods of time.

No, compared to trees that last for 100's of years man made products do not last very long. Compared to old growth forests that last for 1000's of years the comparison is laughable.

I agree with you that National Parks are what we set aside for aseptic reasons, and the rest should be used to be the best long term economic advantage. But your arguments would go down better if you just stuck the facts.

rstuart,

I have been to many of the forests in Tasmania (and to the Amazon for that matter). There are several reasons that the forests in Tasmania are drying out...the primary one is over a decade of drought as experienced across Australia.

If you have any knowledge of a growth cycle of a forest you would understand that a younger (but mature) forest holds a larger volume of carbon than an old growth forest (which is in a stage of sensence - ie dying back or 'negative growth' and as a result releasing carbon).

Again the release of carbon (to the extent that it occurs)from harvesting forests is not a significant contributor to global emissions. If protectionists were keen on doing something for the environment they be attempting to prevent the mining of coal. There would be some good headlines there and some oversized bulldozers to chain themselves to.

@leiverde: old growth forest (which is in a stage of sensence - ie dying back or 'negative growth' and as a result releasing carbon).

So that is where you went wrong. Old forests, even old growth ones, do not die, "die back", or have negative growth. Not without an external influence anyway.

You claim to have been to the Amazon, so surely this was obvious to you. It's been there for 55 million years, pretty much unchanged until we came along. Talk about not seeing the wood for the trees.

@leiverde: If you have any knowledge of a growth cycle of a forest you would understand that a younger

Where do you get this crap from? Just google "carbon sink old young forest" and click on any link. They all explain it in simple terms with pictures, far better than I can.

I often wondered why that "Sir Walter" grass ad on TV featured a guy pulling out a tree, saying grass absorbed more CO2 than trees. It's literally true of course, but surely no one would be sucked in by what almost could be called a lie by omission? Surely it must be obvious to everyone that while grass may indeed absorb carbon at a greater rate than trees, it also dies and releases that carbon at a much faster rate. The trees on the other hand convert it into, well, tree. Well I guess they must have a much higher hit rate with that ad than my faith in humanity common sense lead me to believe.

@leiverde: Again the release of carbon (to the extent that it occurs) from harvesting forests is not a significant contributor to global emissions.

I haven't looked to be honest leiverde. But I'm sure you will understand, given your posting history so far here, that I won't be taking your word for it.

If instead of using timber produced from sustainably managed forests we use concrete or steel, the emissions are orders of magnitude greater. If we lock up our forests and replace timber with steel, concrete of timber from non sustainably managed forests, the emission will still be orders of magnitude greater.

leiverde: old growth forest (which is in a stage of sensence - ie dying back or 'negative growth' and as a result releasing carbon).
@rstuart: So that is where you went wrong. Old forests, even old growth ones, do not die, "die back", or have negative growth. Not without an external influence anyway.

Oh thank you so much @rstuart for the best laugh I have had this month.
Forests are dynamic, in a state of almost constant change. I can take you to places in both Victoria and Tasmania that used to be covered in the beautiful wet forest that most Australians treasure and now have no trees at all due to entirely natural processes. Not through fire, not through human interference, just due to the fact that the individual trees that made up that forest failed to live forever, eventually decaying and being blown over by the wind. If conditions aren't suitable for regeneration of a tree species you may end up with no trees on these sites for hundreds (or thousands) of years before something changes again and a new forest takes over. What is your "Green" viewpoint on this long-term natural destruction of forests? Stop the wind, halt death itself?

How should we manage our National Parks? Should we try so hard to exclude fire? Should we stop the wind from blowing old trees over? Should we re-introduce the human interference present for the last 30-40,000 years? Inject the trees with a special polymer to forever maintain them in the state that we see at this exact point in time?

While I don't condone the last fourty years of Tasmanian forest policy it is people like you who have absolutely no understanding of Australian trees and environments that make a mockery of the native forest debate.

Individual trees don't live forever.
Our natural environment evolves.
Accept these two points as fact before commenting on forest policy.

@gippy: Oh thank you so much @rstuart for the best laugh I have had this month.

I am glad you enjoyed it.

@giggy: Our natural environment evolves. ... hundreds (or thousands) of years

And who argued otherwise?

I think you aren't quite grasping the time frames we are talking about here. Length of time a house stores carbon: maybe 100 years. Length of time a forest lives storing it's carbon: usually 10's of thousands if your claim we had no effect on it is true, or 55 million in the case of the Amazon.

There is a deeper argument to be had here, but seriously: this senescence thing isn't it. The analogy your trying to argue, that forests spontaneously age and die like single organisms do is absurd.