That is interesting about the tree! I thought that only Krypto did something mysterious like that. When chasing a ball in a certain direction, he comes back and before bringing it to us, he ducks into the crate then comes back out. I always say that it's like he's hitting a base in baseball, or something. He used to get on, then off, the couch, again like a base, but not as much since Hira's been here and lays on it.
So, I don't know why Charlie does that, but it's similar in it's ritualistic nature to what we experience.
He sounds amazing. :-)
Love All Life, Thank You For Posting! :)