Spanish moss

Spanish moss (Tillandsia usneoides) is not a moss at all, but a flowering plant in the Family Bromeliaceae (bromeliade) that grows hanging from tree branches in full sun or partial shade from the Southeastern United States through Argentina where ever the warm climate 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 the flowers are small and produced rarely. It propagates mostly by fragmentatsi that blow on the wind and stick to tree limbs (or carried by birds as nesting material). Spanish moss is not a parasite, but an epiphyte, 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.

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 humans' skin and cause considerable itching). At one time, some 5000 tons of Spanish moss were harvested and used in the U.S. alone. The plant is susceptible to air pollution.

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