If memory serves me correctly, that is actually a fungus. You're right, in parts of the country it will cover a tree in no time-- other parts, people have never seen them.
This is the "air plant" I don't remember it's proper care, but when I was young I harvested a lot, bought some small pots and made a fortune on a family trip out of state.
"It's not what you buy, it's what you build" -Unknown
29G, Eheim 2232 X2, DIY CO2