Delta Journal
by Bob Thomas

One of the magical views in the southern United States is a forest festooned with Spanish moss. Many believe that this moss (actually a member of the pineapple, or bromeliad, family) is parasitic on the tree, but it is not. It simply uses the tree as a resting place, and is not connected to the tree’s circulatory system at all.

Such plants are called epiphytes – plants that simply grow upon other plants. Temperate zones are not characterized by an abundance of epiphytes, so those that occur are notable. An uncommonly seen, yet very interesting, epiphyte in Louisiana is the Green Fly Orchid, found cryptically living on the trunks of tupelo gum and magnolias.

If you want to see epiphytes in all their glory, visit the tropics. The species diversity is immense and their weight borne by the limbs of rainforest trees is enormous. As one would expect, the diversity of many types of living things, including frogs, spiders, insects, butterflies, and more, increases sharply in response to the epiphytic jungle’s myriad of niches.

A related biota is the epiphyllus community. Epiphylls are species that live on the surfaces of leaves, thorns, spines, twigs, and the like. They include tiny plants, algae, and microbes of all sorts.

Plants everywhere have epiphyllus communities, and the casual observer rarely notices their presence.

It is the bacterial epiphylls that cause frequent, and often nasty, infections from puncture wounds by spines in the tropics.

The next time you walk a forest for the pure pleasure of the surroundings, think not just of the trees, but of the true diversity of the forest. Above ground, that includes rooted vegetation of all types, plus the epiphytes and epiphylls.

Also published in Nature Profile, The Times Picayune, July 28, 1982.