What Is Not Killing Your Tree: Spanish Moss
Dr. William Lester, UF/IFAS Extension Hernando County
Dr. Kathleen Shields, UF/IFAS Hernando County Extension Master Gardener
Did you know?
- Spanish moss is neither Spanish nor a moss.
- Spanish moss is not a parasite; it gets all its nutrients from the air and rainwater.
- Spanish moss has a key role in Florida’s ecology.
Our office receives frequent calls from residents worried that their tree is being killed by Spanish moss. Contrary to widely held belief, Spanish moss is not a parasite. It is an epiphytic plant that grows on another plant but does not utilize the host plant for nutrients. Epiphytes, sometimes known as “air plants”, get all their nutrients from the air and rainwater, and they make their own food. Spanish moss does not have any roots. It uses its long, scaly stems to wrap around the host tree and hang down from the branches. The stems are covered with cup-like, permeable scales that retrieve moisture and nutrients from the air and from pockets on the surface of trees. The plant’s tissues can hold more water than it needs, so it can withstand long dry periods, and in extreme droughts, it becomes dormant until moisture returns. When the tissues plump up after a rain, Spanish moss appears greenish, and as the water is used, it returns to a gray hue.
Spanish moss is not a type of moss; it is a bromeliad, related to pineapples and many popular houseplants. It does not exist in Spain but is native to Central and South America and the southeastern US. Native Americans called it Itla-okla, which meant “tree hair”, but early French explorers thought it looked like the Spanish conquistadors’ long beards, so they called it “Spanish Beard”. Over time, Spanish beard became Spanish moss.
Spanish moss produces tiny seeds with feathery appendages that allow them to float through the air, but it is more likely to propagate from fragmented pieces carried by birds or the wind. Many animals use Spanish moss for protection, taking cover in the thick masses. Several species of songbirds use the plant material for nest building or weave their nests in clumps of moss. While the plant is not parasitic, heavy accumulations can weigh down branches and over-shade existing foliage. Dead and declining trees generally have numerous bare branches that easily catch wind-blown moss, while healthy trees generally outgrow any moss that lands on them. You do not need to remove Spanish moss from your trees, but if you do not like the look, use gloves or a hook to remove any accumulations. Having your trees sprayed with a copper fungicide is not recommended because it turns the moss into black slime in the tree, which is neither healthy for the tree or attractive.