Have you ever seen long gray-green fuzzy vines hanging off Oak or Cypress trees? The image of a draping garland of Spanish moss hanging from majestic trees reminds us of hot summer days in the south. Many consider Spanish moss beautiful, perhaps adding a bit of romance to the landscape, while for others it creates a bit of spookiness.
If you take a closer look into the branches of trees you may find ball moss, a roundish ball shape relative of Spanish moss. Ball moss, Tillandsia recurvata, and Spanish moss, Tillandsia usneoides, are epiphytes, the largest genus in the bromeliad family. Epiphytes grow on the surface of plants using them as a support, and are not considered parasites because they draw no nutrients from the plant they settle on, but “catch” moisture and nutrients from the air. Ball moss is spread by windblown seeds that develop into small green tufts and then a dense ball of numerous individual plants. Ball moss develops pseudo-roots called “hold fasts” that help anchor this gray-green colored sea urchin like tuft onto the surface on which it grows. Ball moss and Spanish moss grows well in low light, low air movement and high humidity, most often in the bare interior canopy of trees.
While creating an unsightly appearance, these mosses (which are not true mosses) have the benefit of providing nesting materials to birds, including the Ruby-throated Hummingbird, and because insects can live in the moss, a place for birds to search out food.
Spanish moss, a kind of rope like version of ball moss, can reach lengths of 20 feet and become heavy, especially when wet, enough to break a weak branch. Although not considered harmful initially to the trees they invade, both mosses can damage the host if allowed to multiply enough to overshadow leaves and reduce photosynthesis or restrict areas of new growth. Some sources agree an over-abundance is detrimental to the overall health of the tree in the long run. Control is easiest when growth has not gotten out of hand.
If you choose to remove it, the best treatment for ball moss is a combination of picking, pruning and spraying. Hand pick what you can safely reach, a cherry picker or claw like tool that extends will help. Prune dead limbs and lightly thin the tree canopy to allow more light to the inner portions of the tree if necessary. Finally, apply a copper fungicide as directed to areas where the balls were removed before new masses can take hold or thoroughly saturate the ball moss if unable to remove. Apply the fungicide before or during rainy season, mid-February to early May. Use caution when using a copper fungicide as it can be injurious to nearby ornamental plants, and may react to metal surfaces on nearby cars, lawn furniture and metal roofs and can cause staining on driveways.
The ball moss will die over the next several months but remain until the “hold fasts” decay. A second application may be necessary, apply it about 12 months later. Since it doesn’t have root tendrils and is not anchored, the best method to remove Spanish moss is by manual removal; chemical treatments are not recommended.
Next week I’ll talk about lichens, another type of epiphyte.
