Sacha wrote in :

On 2012-12-07 21:17:03 +0000, "Kate Morgan"
said:

Freecycle is a brilly place to start.
I have had to start bedding our pony on wood shavings as I could not
get small bales of decent straw. It did cross my mind that no one
would want want my muck heap but find a wood shavings muckheap is
just as popular as straw.

kate

It's a long time since I was into horses but don't a lot of people use
wood shavings now? I can't think why they wouldn't be as popular. It
all rots down the same way. ;-)

One reason that springs to mind is that is that in some cases preservatives
are added to the timber, such as Tanalising which contains 'Tanalith E'.
You don't want that in your stable! Copper, Chrome and Arsenic are in that
chemical compound.
It might rot down harmlessly, I don't know.
Just a warning of what MIGHT be in those 'shavings' or sawdust.(the sawdust
will contaminate the shavings)

http://www.archtp.com/

Make your own mind up about it.(dig deep)

Baz