Gavin butcher photo Manjimup-Bridgetown Times
Analysis of publicly available data by respected scientist Dr Lachie McCaw has shown that claims by Premier McGowan and his coterie of Forestry Ministers, Jarvis and Kelly, to be without substance. Source: Australian Rural & Regional News
The WA government had stated that one of the reasons the timber industry had been axed was because the trees are no longer growing.
Dr McCaw has used published data on the long-term forest monitoring plots called ForestCheck to demonstrate that the harvested forest is growing, and the uncut forest is in decline. His paper, which appeared in the March edition of the forestry profession journal, The Forester, summarises data published last year and is the result of 20 years of monitoring forest growth.
ForestCheck was established to monitor how forests recover after timber harvesting and burning. It compares recently cut over forest with long undisturbed areas by measuring the growth of trees, the structure of the forest and its biodiversity (from fungi and lichens to insects and mammals) and how they change over time.
The results to date have been astounding. They show that the forest ecosystem is highly resilient to disturbances like fire and harvesting, and that it recovers rapidly.
Dr McCaw, a former senior scientist at the Department of Biodiversity, Conservation and Attractions (DBCA), looked at the most recently published data and was able to conclude: “These data demonstrate that jarrah forest subject to timber harvesting and silvicultural treatment has regenerated successfully and continues to grow despite potential adverse effects of climate change. The potential for active management to dramatically increase growth rates is also demonstrated.”.
Figure 1 provides clear evidence of the vigorous growth of harvested forest when compared to the unharvested reference areas.
This evidence was ignored by the government in making its case that the forests are somehow not growing. Papers tabled by the previous Minister for Forestry failed to cite the recent research by its own scientists and relied upon general climate trends by the Bureau of Meteorology and the CSIRO. The Minister for the Environment went even further by refusing to table any reports when asked to do so.
The ForestCheck data is even more surprising. It shows the undisturbed forest to be potentially at greater risk that the regrowth forest. One third of its reference areas (grids) actually had negative growth. According to Dr McCaw this was ‘mostly attributed to loss of large mature trees resulting from senescence unrelated to fire (1 grid), storm blow (1 grid), bushfire-caused mortality (2 grids) and collapse of trees following prescribed burning (8 grids). It seems likely that under conditions of climate change that these forests could be more vulnerable than the forests that are thinned and managed.
We also know that old forest is at a steady state, where the growth and death of trees is in balance. In other words, old forests lose as much carbon as they gain. Yet the populist logic of the Forestry Ministers claims that these areas will be valuable carbon sinks. The reality is that they are at capacity and are not helping to reduce CO2 in the atmosphere, whereas actively growing forests and long-life timber products are demonstrably beneficial means of removing and storing carbon.
This was well demonstrated in 2013 when DBCA indicated that the WA forests, with sustainable harvesting, would increase its sink by up to 30 million tonnes of CO2–equivalents. The current published forest plan can make no statement about carbon storage because “there wasn’t sufficient funds”.
In defiance of the science, McGowan’s Forestry Ministers have continued to claim black is white and the earth is flat when it comes to forestry. It’s time for the government to come clean and admit its decision to stop native forest harvesting was devoid of any science and simply a political play to appeal to its green fringe.
Gavin Butcher is a former director of the WA Forest Products Commission.
