[Greenbuilding] Alternatives to Pressure Treated Wood

[Chris Green]

Mary Bull - Greenwood Earth Alliance wrote:
> Where do you get that North American NW
> forests are only 10,000 years old, 
He's talking about the parts of North America which were either covered 
by sheets of ice or where nearly barren arctic tundra lands near the ice 
fields. The ice sheets started disappearing about 12,000 years or so 
ago. It took a while for forests to migrate north and or inland again.
Right near where I live there used to be 2 kilometers of ice. Later on, 
as the glaciers retreated and grasses started growing, Wooly Mammoths 
moved in, and following them, hunters.

Many millions of years ago it was a lot warmer. Dawn Redwood trees 
(Metasequoia, not your Coastal redwood ) grew on the northernmost arctic 
island then. In fact, you could go up there and dig up a multi-million 
year old stump and use it for firewood. That's why our geologists won't 
tell anyone exactly where the fossil forests they study are, but they 
are somewhere on Axel Heiberg Island. I think the forests disappeared 
about 35 million years ago towards the end of the Eocene era.
http://en.wikipedia.org/wiki/Axel_Heiberg_Island

http://en.wikipedia.org/wiki/Metasequoia

The Amazon region never experience the ice ages, so the forests have 
grown there since trees first evolved and South America was still 
attached to Africa.

Cheers,

Chris Green.