Spanish moss (Tillandsia usneoides) closely resembles its namesake (Usnea, or beard moss), yet is not a moss at all. Instead, it is a flowering plant in the family Bromeliaceae (the bromeliads) that grows hanging from tree branches in full sun or partial shade. It ranges from the southeastern United States to Argentina—wherever the climate is warm enough and has a relatively high average humidity.

The plant thallus consists of thin, curved or curly, heavily scaled "leaves" that grow vegetatively in chain-like fashion (pendant) to form hanging structures up to several feet in length. The plant lacks roots and its flowers are tiny and produced rarely. It propagates mostly by fragments that blow on the wind and stick to tree limbs (or are carried by birds as nesting material).

Close-up of Spanish moss

Spanish moss is not a parasite like mistletoe, but rather an epiphyte (air plant), which absorbs nutrients (especially calcium) and water from the air and rainfall. It can grow so thickly on tree limbs that it gives a somewhat "gothic" appearance to the landscape, but it rarely harms the trees (except for the extra wind resistance in hurricanes).

Spanish moss is sometimes bought for use in arts and crafts, or for beddings for flower gardens, but the plant in its natural habitat can contain chiggers (which burrow under human skin and cause considerable itching).

At one time, some 5,000 tons of Spanish moss were harvested and used in the U.S. alone. The plant is susceptible to air pollution.

References

• Mabberley, D.J. 1987. The Plant Book. A portable dictionary of the higher plants. Cambridge University Press, Cambridge. 706 p. ISBN 0521340608.
• ITIS 42371 2002-08-25