Despite its name, Spanish Moss (Tillandsia usneoidesand) is actually a rootless bromeliad that gets moisture and nutrients from the air. You can let it hang from a windowsill basket (it's shown here with other air plants), or use it as a mulch around other houseplants. If you gather the moss from trees, remove any insects by submerging the moss outdoors in a bucket of hot, soapy water. Rub it between your hands, then rinse it and spread it in the sun until it's completely dry. If any pests remain, put the moss in a bag, so the pests won't get out in your home, and boil it. Again, let it dry completely before using it.