but you asked if they could eat them. in any case, when it comes to edible treats, just stick to oats, shreddies, rosehips, and other safe treats. but its best to give treats in the form of chew toys anyways. pick 2 edible "treats" and just change them out (i only feed oats and chinnie flower salad as treats- wood toys the rest of the time).
if youre looking for supplies and wood...nuts? i know that people use coconut shells, but since chins chew EVERYTHING, its unavoidable that they may consume something. just stay clear of nuts for any purpose. a few members have this motto: K.I.S.S. (keep it simple, stupid). stick with the treats you know and the woods you know are safe. there's no need to experiment.