exofytisch

Exofytisch is a term found in some texts to describe organisms that grow on the surface of another plant, typically on bark, branches, or leaves, without deriving nutrients from the host’s interior. In botany and ecology the more standard term is epiphytisch (epiphytic). The usage exofytisch is less common and is often considered a variant or nonstandard spelling; in contemporary German literature epiphytisch is preferred.

Epiphytes span a range of taxa, including many vascular plants, mosses, and some lichens and algae. Typical representatives are orchids and bromeliads that grow on trees in forests, as well as various ferns and mosses that occupy bark or rock surfaces in humid environments. Epiphytische organisms differ from parasitic plants in that they do not extract sustenance from the host; they mainly use the host for physical support and access to water and nutrients available in rain, dew, or through atmospheric deposition.

Adaptations common to epiphytes include specialized aerial roots or velamen to absorb moisture from the air, leaves adapted to store or capture water, and in some groups, CAM photosynthesis to optimize water use. Reproduction often relies on wind dispersal of tiny seeds; for some orchids, seed germination is dependent on symbiotic fungi.

Ecologically, epiphytes contribute to forest biodiversity, create microhabitats for invertebrates and small plants, and influence nutrient cycling. They are sensitive to changes in humidity and forest structure, making them indicators of environmental health and targets for conservation in tropical and temperate ecosystems.