This essay on "Epiphytism" by E. Poeppig was published in Journal of the Bromeliad Society vol. 31(6):252 in a translation by Harvey E. Kendall. "...Parasitic growth is prevelant in all tropical areas, even at some distance outside the tropics, but they increase the closer you get to the equator. It is especially in the very thick sub-alpine forests, in which they are present in an over abundance and where they even appear in a ratio of 1:11 to the remaining phanerogams .... They are almost more interesting than the growth on the ground. Their multiplicity is so great that in Peru alone it would take a lifetime to look at the species and determine the laws that govern their growth. Mere description can never give an idea of the appearance of a bombax tree whose giant branches are so laden with hundreds of parasites that its white bark is not visible anywhere. The parasites often are so dense on the tree trunks that neighboring plants prevent each other from spreading out, and so it happens that one layer of vegetation grows over the other even causing one parasite to seek root on top of another. It is a very one-sided viewpoint to consider parasitic plants as killers. There is no doubt, however, that a great many of the plants of this type can have a secondary effect on the destruction of a tree or even an entire forest. It is interesting for the lonely observer separated for many months from the world in the darkness of that forest observing nature and following its progress with ever greater involvement. I present to you some findings resulting from observations made by me on the behavior of parasitic vegetation." "Nature goes about the destruction of a tropical tree in approximately the following manner. No matter how smooth the surface of its trunk, soon slightly crust-like spots appear, then small, flat, reddish brown lichens followed by mosses, and the surface becomes uneven. Small Tillandsia's now root onto the surface and sit there for a long time without growing significantly, seemingly happy to have found a modest home. Gradually they form small turfs on which polypods and such soon begin to grow; the latter are much less modest as they send out their rooting stipites in all directions looking for a spot where they can divide and form a new colony. Then come the orchids and hanging cacti and form a veritable bed on which bromeliads and larger orchids can settle; they form thick protusions with their mighty root masses and thus cause earth to collect. From the ground a large aroid has already been creeping stealthely upwards as the slick wood tries everywhere to reject it. It barely reaches the protrusions of the parasite group when it strikes root and impertinently sends out its broad leaves covering the work of the initial stages of destruction. Along with the aroid, invading loranths bore into the wood and send out their suckers in all directions. Then comes a woodpecker and makes a hole in the wood, which will perhaps be occupied later by a colourful ara bird, who will widen it with its stout beak into a comfortable nest. New groups of parasites arise close by until they join with the earlier ones and eventually a single, great mass arises, which completely covers the branch or surrounds the perpendicular stem like a ring. A lot of earth collects on it drawing moisture and probably storing rain water. Now rot seriously attacks the whole spot and numerous insects further the decay and in turn attract more legions of woodpeckers. Only now does nature begin to show its powers, for soon sapping bushes appear as do fungi and large ferns and especially termites, which now occupy this hanging garden as their great activity in constructing their houses and in fetching materials for their survival speeds up the decay." "After a few years have passed the demolition has progressed greatly. Numerous vines rising from the ground have enveloped the victim and hang on it or pull on it with the tension of their ropes. Finally a blast of wind breaks off the weakest branches, and soon the stem follows as its whole gigantic length falls, which a few years ago could have resisted the best axe. Far and wide the fertile ruins cover the naked ground; vines, twining grasses, nettles, tradescantias all take it over, then in a few months a thick layer of brown humous covers the formerly unproductive ground, and nature has completed its benevolent work." |