Ramalina usnea

Ramalina usnea is a species of corticolous (bark-dwelling), fruticose lichen in the family Ramalinaceae. It grows on tree bark across the Americas and parts of East Africa. Growing up to 30 cm (12 in) long, it forms pale greenish-grey branching strands that darken when dry. The species is highly adaptable: it forms coarse, flattened branches in foggy environments and develops finer, more delicate forms in humid coastal areas. First described by Carl Linnaeus in 1767, it underwent a few taxonomic revisions until Reginald Heber Howe, Jr. established its current name in 1914. Unlike many lichens that grow primarily at their tips, R. usnea expands along its entire length by continuously rebuilding its cell walls. It serves as an important component of some ecosystems, particularly in the Galápagos Islands' transition zones, where it forms characteristic draperies on trees and is used as nesting material by certain birds....read more on Wikipedia.