27 March 2007

Diversity is healthier for humans, and forests

The reported health effects from solvent-treated timber confirm the need for New Zealand to diversify its forestry, and to ensure more planting of species that do not require chemical treatment, Green Party Co-Leader Jeanette Fitzsimons.

"For many years, the Green Party has called for a move away from our pine monoculture to a range of species that are fit for purpose, without the use of toxic materials," Ms Fitzsimons says.

"Timber treated with copper-chrome-arsenic causes serious pollution of waterways, where the heavy metals interfere with the breeding of aquatic organisms. The mixture is also highly toxic to humans, with long lasting effects on health and wellbeing.

"Treatment with light organic solvent preservatives ( LOSP) was introduced partly to reduce the dangers of treatment with copper-chrome-arsenic mixtures, but is now being shown to have its own problems.

"Pine monocultures are also risky, from a biodiversity point of view. All of our pine forests are very closely related and a single pathogen able to bypass their adaptive defences could devastate them. This will become more likely with climate change, which will render New Zealand habitable for pests not here now.

"It is possible and safe to build a complete house with macrocarpa with no treatment at all, provided it is not used below ground. I did it 12 years ago and the house is still totally sound," Ms Fitzsimons says.

"New Zealand already grows some Douglas fir, which is a good option. Our conditions can also support excellent eucalypts and decorative timbers such as Tasmanian Blackwood. None of these species need chemical treatment.

"If New Zealand had planted more macrocarpa and other durable species when I first started calling for it, those forests would now be mature and we could be building with them.

"It is not too late to start, to provide for sustainable building timbers in future. The Greens' climate change policy proposes that the replanting incentive be increased for species that reduce our reliance on pine.

"The Government's permanent forest sinks initiative, legislated for last year, also allocates carbon credits to permanent forests which are not pine, and this programme allows for limited selective logging after an initial period, provided the canopy is maintained," Ms Fitzsimons says.

ENDS

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