we have got a 9 week old labrador puppy who has taken a liking to bark chippings
can they harm him as i am always seem to be taking them out of his mouth

A while back there was a topic on bark chippings, apparently one certain type was dangerous to dogs, I'll have a look back see if I can find anything.

Found this in a previous discussion:-

Dogs have also been poisoned by the theobromine found in cocoa bark chippings in garden borders so gardeners with dogs need to be aware of the danger.