I have recently moved into an older house and have a lovely old Texas Green Ash, which is probably at the end of its lifespan. There is a chain wrapped around and embedded in a large limb. Would it be better to leave it alone or cut it away from the limb? Some links are almost completely grown over.

At this point you will do more harm than good trying to remove any embedded chain. Cut away any exposed chain you can without harming the tree.
Tony M

Thanks for the quick response. When I thought about the damage it would do to pry or cut out the chain, I couldn't imagine it being healthy for the tree... worth the price of membership!