We were both lucky and surprised with Willows reaction to our tree last year but on a plus side she was nearly one years old when we put the tree up for the first time.
We got her a new doggie chew and toy, gave it to her in the same room where we did the tree. She sniffed the boxes etc but didnt try to take anything,not even the baubles.
We made sure we put it up on the friday night so we had all weekend with her to make sure she didnt try and do any damage. We leave her in the lounge where the the tree is when we are at work so we had to be sure by the monday that she had no interest in it.... We were pleasantly surprised
Every time she went close when it was up we just said, 'Ahhhh ahhh' and called her back to her toy and chew. She was fine with everything but wasnt keen on a snowman we have at first and she barked at it and was unsure. All in all she was really good. Hoping this year is the same