I would appreciate and even share this humor with someone if I knew they didn't seriously hold the view that there was something wrong, stupid, or misplaced about loving trees. The problem is that it represents a serious form of ridicule couched as humor. Humanism is a real problem, where people have a real ego-defense reaction when environmentalists or others suggest that it's possible to appreciate non-human entities as much or more than human beings.

Think about the people who took what I said about human consciousness being special and challenged me by mentioning animal consciousness also being special. What if I had reacted in an ego-defensive humanist way and ridiculed them as loving cats more than people? What if I had told them that if they think feline consciousness is so special, why don't they marry a cat or adopt a cat as a child, etc.? That would be more than just humor, it would be ridicule subtly aimed at putting them down for appreciating cats instead of discriminating against cats in favor of praising humans.

Don't you see that goes beyond humor?