I've just got a border terrier pup and was told to give her a piece of wood to chew on, I've got some small pieces of plum wood for her, is it safe for her though?
I wouldn't give her wood to chew on - too much of a risk from splinters and pieces getting stuck in the throat and across the rood of the mouth. There are plenty of safe 'chews' for her to have which have already been suggested, just make sure it's of a suitable size for her.
If she is teething try putting raw carrots in the freezer then giving them to her to play with/chew on. Pigs ears or marrow bones are good too and you can give raw chicken wings. For general play chewing use the inside of toilet rolls and kitchen rolls and plastic milk bottles with the tops off (and the plastic rings cut off).