Spanish moss

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A bromeliad plant (Tillandsia usneoides) that is epiphytic on trees from the southern United States to Argentina, having greenish-gray stems and leaves that droop in long matted clusters.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun dense festoons of greenish-grey hairlike flexuous strands anchored to tree trunks and branches by sparse wiry roots; southeastern United States and West Indies to South America