Bayou-Diversity (4 November 2018) Spanish moss is not. What I mean is that Spanish moss is not Spanish and is not a moss. It does not grow in Spain but rather in the southeastern United States down into South America. It is not a true moss like sphagnum but rather a flowering plant in the bromeliad family very closely kin to pineapples. Often associated with our images of southern swamps, Spanish moss grows on trees in long, draping, thread-like, gray veils where it absorbs moisture and nutrients from the air. The plants are not parasitic and don’t harm their host trees.
Many types of wildlife use Spanish moss in their life cycles. Squirrels and birds use it for nest materials. Parula warblers build their nests almost exclusively in draping clumps of the plant. Some species of bats roost in Spanish moss, and it is the sole habitat for one kind of jumping spider.
Humans have used Spanish moss for centuries. Early European colonists recorded Native Americans wearing clothing made from the plant. Louisiana Cajuns made a concoction of mud and Spanish moss known as bousillage for mortar and house insulation. Later an entire commercial industry developed around the harvest and processing of the plant into manufactured products. It was used for packing materials, mulch and in saddle blankets. Thousands of tons were ginned and used to stuff mattresses until as late as 1975 when synthetic fibers replaced the natural filaments. Recently, researchers at ULM have studied components of Spanish moss as a possible drug to control blood pressure.
Because Spanish moss receives all of its nutrients from the air, it is very sensitive to wind-born pollutants such as heavy metals from exhaust fumes and pesticides. Early explorers in Louisiana often remarked about the dismal, dreary atmosphere associated with moss-laden swamps. We now know that the presence of healthy Spanish moss is an indicator of good air quality, and is thus a welcomed part of our bayou scenery. (adapted from “Bayou-Diversity: Nature & People in the Louisiana Bayou Country,” LSU Press)