Epiphyte - Physiognomy

Physiognomy

Epiphytic organisms usually derive only physical support and not nutrition from their host, though they may sometimes damage the host. Parasitic and semiparasitic plants growing on other plants (mistletoe is well known) are not "true" epiphytes (a designation usually given to fully autotrophic epiphytes), but are still epiphytic in habit. Plants such as New Zealand species of Griselinia, which send long roots down towards the soil while fixed high in another plant and reliant upon it for physical support, are also epiphytic in habit.

Some epiphytic plants are large trees that begin their lives high in the forest canopy. Over decades they send roots down the trunk of a host tree eventually overpowering and replacing it. The strangler fig and the northern rātā (Metrosideros robusta.) of New Zealand are examples of this. Epiphytes that end up as free standing trees are also called hemiepiphytes.