Epiphyte

An epiphyte is a plant that grows upon another plant (such as a tree) non-parasitically or sometimes upon some other object (such as a building or a telegraph wire), derives its moisture and nutrients from the air and rain and sometimes from debris accumulating around it, and is found in the temperate zone (e.g., many mosses, liverworts, lichens and algae) or in the tropics (e.g., many ferns, cacti, orchids, and bromeliads).

Read more about Epiphyte:  Botanic Subdivision, Physiognomy, Nutrition, Ecology