How do epiphytic ferns grow on trees without being parasites?

It is a common misconception that epiphytic ferns are parasites; however, they are not parasitic because they do not derive water or nutrients from their host plants.12

Epiphytic ferns use trees merely for physical support to reach higher levels of the forest canopy, where they can access more sunlight. Unlike parasitic plants, which possess specialized organs called haustoria to penetrate a host and extract resources, epiphytic ferns remain entirely independent of the host's vascular system.132

Instead of relying on the tree, these ferns obtain moisture from rain and water vapor in the air, often absorbing it through their roots or specialized leaves. They acquire necessary minerals and nutrients from organic debris, such as decaying leaves, that collects on the branches and trunks of the supporting trees. By growing in the canopy, they effectively exploit a niche that provides the light and moisture they need to thrive without harming the trees that support them.13