How old does a WA Karri Tree have to be before it is considered to be "significant"?

Question

The Forest Products Commission did not consider a 500 year old tree cut down to be significant. Spokesman Gavin Butcher says; "The protecting our old growth forests policy protects large areas of old growth forests and there are opportunities for individual trees to be registered, and trees like this and much bigger than this are protected in those systems..."

http://www.abc.net.au/news/stories/2008/06/04/2264548.htm

Answer 1

Since Karri trees grow fairly quickly and for around a 1,000 years most areas around Pemberton and /Margaret River have been 'logged' in cycles since the 1800's.

A 500 year old tree would be middle aged, but might be significant in as much as the 'block' of forest was either previously unlogged or they deliberately left some old trees previously. (I assume the later, as other trees in the picture are clearly young).

I suppose that this indicates that the rotational logging of 'blocks of forest' have now become 'clear felling' which is where every tree is removed and the whole block is replanted. (This makes mechanised felling easier in the future).

From a environmental perspective this is good for oxygenation as young trees are much better for replenishing the world's oxygen and taking carbon out of the environment.

But trees are not as good as this as grasses which acre for acre are far superior at carbon reduction.

However from an ecological perspective, clear felling does not leave behind islands of habitat sanctuaries for birds, and animals. Although this idea is debateable as I've seen blocks that had been turned into dairy farms around Pemberton and elsewhere, where a mature tree or two has been left on it's own. These paddocks are just as sterile.

It would seem far better to have reasonable size groups of trees left as 'pockets of forest' to better provide habitat sanctuary.  

The ferals would condemn any felling at all, and would see the felling of an older tree as an opportunity to get the issue into the media so that they can stop all logging. There are some that reject all modern ways of living, and want everyone to live 'sustainably off the land'. Unfortunately for them the world's population passed this point of being able to do that some centuries ago.