Any of several lichens, of the genus Usnea, that generally grow hanging from tree branches, resembling grey or greenish hair.
Bryoria fremontii (wila), a lichen eaten by First Peoples in North America.
Any of numerous species of dark-coloured mosses (Bryophyta), possibly species of the genera Grimmia, Andreaea, Syntrichia, Cinclidotus.
Nostoc flagelliforme (fat choy), a terrestrial cyanobacterium eaten in Chinese cuisine.
Tillandsia usneoides (Spanish moss), a flowering plant, particularly after it has been dried for use as stuffing and decoration.