Vexillology

The last part feels weird to me. Are there enough tree flags to say that the "vast majority" of them do anything in particular?

Also, fun fact, palm trees aren't trees depending on the definition! "Tree" is one of those things that doesn't have an easy way to define it, but a common one in biology is a plant that produces a woody trunk with secondary growth, which is the growth process that gives trees their rings. Palms grow more like flowers that just happen to be really big and sturdy

Of course, the colloquial definition of tree is more of a "it looks like a tree" sort of deal, in which case palm trees are absolutely trees