Epiphytes

Some plants which may be mistaken for stem parasites are the Epiphytes which grow in trees usually in tropical areas, and many of the mosses come into this group. The difference is that epiphytes are normal green plants which have taken to a life of growing on the bark of tress but do not gain any of their nourishment from them. They live entirely on what food materials happen to be lodged in the crevices of the bark and a lot of orchids which live in this way send out thick white roots capable of extracting water from the damp tropical atmosphere.