Most Plants generally send their roots into the ground to absorb food and water. An air plant is different. It uses its roots to anchor itself to a tree. However, it is not a parasitic plant that steals nutrients and moisture from the host plant. Instead, an air plant manufactures its own food, relying on its host to serve only as a base of operation. In fact, the many thousands of varieties of air plants – that include lichens, mosses, liverworts, Spanish moss, and some ferns, orchids, and cacti – may also grow on rocks, buildings, timbers, and telephone wires.
Bromeliads are also air plants. The largest and most colourful of the bromeliads grow in the rain forests and jungles of Central America and South America. The pineapple, probably the most familiar edible air plant, is the bromeliad that grows on the ground.
The leaves of the world’s 2,000 kinds of bromeliads are typically long and narrow, providing lots of surface area of specialised scales, called trichomes. Trichomes serve two important purposes. First, they absorb food and moisture from the rain and fog of tropical forests. Second, they reflect sunlight, preventing the bromeliads growing high in trees from getting sunburned.
The leaf-base of many bromeliads forms a cup that collects water, while the leaves make a protected nestlike structure. Mosquito larvae, tree frogs, and spiders have their homes in the miniature ponds of these plants. When rain is scarce, the bromeliad uses the stored water and food (the latter in the form of dead insects) to stay alive until the next rainfall.
