Stanon

I worked for the Forests Commission in the late 1970s and early 1980s before it was dissolved and absorbed into a much bigger mega-department. I don't ever recall that sort of discussion because native forest timber production was essential (we had far fewer plantations at that time), and the propaganda campaigns against its very existence were only just beginning.

Nevertheless you make a reasonable point - the 6% figure is based on the net available area designated for current and future timber supply (ie. ~450,000 hectares) as a proportion of the 7.1 million hectares of public forest of all types. There is also another million or so hectares of privately owned native forest which is almost all not used for any commercial purpose.

About 15-years ago when writing a book on this subject, I subtracted mallee and other unharvestable forest types from the total public forest area and came up with a figure of about 13% of the potentially harvestable forest area that was available for use. It would quite a bit less now given the extent of reserve expansion since then, and the forced closure of the industry from other areas, such as the Wombat Forest where there are substantial areas of harvestable forest types that have yet to be added to the conservation reserve estate.

As for the wet sclerophylle forests in the Central Highlands, which are arguably Australia's most valuable native timber resource -- somewhere between 70 and 75% is either reserved or not available for use due to management constraints -- and this is increasing on an almost daily basis as new reserves are declared around each new Leadbeater's Possum detection -- there have ~650 of these since 2014.

So, yes the 6% figure is technically correct albeit a bit misleading, but whichever way you look at it the vast majority (~90%) of potentially usable forests are not available or suitable for use.

1/The forest definition I described ie 100ft came from an official Forest Commission resource kit for schools from the 1970's. The debate regarding these issues was part of the Forest's Education Project of the Kirner era prior to the introduction of the VCE Environmental Studies course.
2/ I see a need to factor in areas now in national parks which have already been logged.
3/ Despite winding back the rotation times in the Wombat forest it could not supply the permitted timber allocations.
4/ Much of the timber resources in high rainfall areas are off limits because they are in vital water harvesting areas, where the water is of more value than the timber.
5/ Rotational harvesting on cycles of 100 years or less converts native forest into even aged juvenile forest. These unless thinned have a much greater tree density, a lower canopy, much diminished soil moisture, runoff and water quality see 4 above. They also have an increased flammability and reduced species diversity.
6/ The required flora and fauna surveys have often not been carried out by Vicforests prior to harvesting thus private bodies have conducted these and then taken legitimate court action to see the Act is obeyed. Resulting in a number of losses in court for Vicforests.
7/ I think the only stand of old/growth box/ironbark forest in the state is on a small area of Mt. Rushworth.
8/ A more useful figure to publicise would be what % of old growth wet sclerophyll forest remains from what existed at the time of settlement

Stanon, explorers and pioneers called mountain ash blackbutt. When they started clearing Strzeleckis in 1870s they found scattered old trees and two age classes of young regrowth as well as clay ovens, stone axes and spearpoints and grindstones. First megafire was about 1824 after Aboriginal burning in Strzeleckis and Central Highlands was disrupted by 1789 smallpox epidemic. Next in 1851, less than 2 decades after Europeans arrived - 5 million hectares. Then 1898, 1926, 1939, etc. etc.. Megafires have virtually eliminated old growth so-called wet scleropyll. Logging impact has been miniscule in comparison.

Stanon - response to some of your points
2) Surely, the main point is that forests in NPs won't be harvested again. Forests are inherently dynamic and always changing in response to disturbances. Areas regenerating after past timber harvesting may be 100 years old or more and have regained their pre-harvest values. There would be few records of extent of older harvesting, and in any cases such areas have probably also been impacted by subsequent fires. The reality is that without past harvesting of native forests, we would not have developed as a society given that up to the mid 1990s it was our primary source of wood, and was virtually our only source of wood for most of the time since European settlement.
3) The Midlands Forest Management Plan prepared in the early to mid-1990s placed about a quarter of the Wombat State Forest into conservation zones where timber production was suddenly excluded. There was a corresponding bureaucratic failure to reduce the timber allocations in accordance with the suddenly reduced resource base, which then led to a period of over-harvesting which was then corrected in the early 2000s.
4) Yes, but 12% of Melbourne's water supply catchments are still used for limited timber harvesting. The other 88% are now national parks -- so they provide for both water and conservation.

Stanon - continued response to your points:
5) Fire can also convert older forest into young even-aged regrowth, and does so on a far greater scale. The 2009 Black Saturday fires, from memory, burnt, in just a few days, an area of forest that it would have taken 150 years to harvest and regenerate at the then annual harvesting rate. A bit of perspective is needed on this.
6) In fact, VicForests have won most of these legal challenges. Environmentalists are able to mount such cases despite having no assets and often with the help of pro-bono legal services. In one of biggest cases, the group My Environment lost and was required to pay VicForests costs - from memory $1.2 million - which has yet to be paid because they have no assets. These cases are a blight on the Victorian taxpayer forced to foot the bill to defend them.

Overall, your comments suggest a lack perspective on these matters -- as another comment has noted fire and even past human activities in the pioneering era are mostly responsible for the lack of old growth forest. For example, the Wombat forest was completely felled for mining timbers and firewood between 1855 and 1900. I would imagine similar pressures were endured by the box-ironbark forests. The managed harvesting and regenerating of forests for wood products under the stewardship of foresters over the past century has had a comparatively minor impact.