Bill Dunson, born in rural Georgia, skipped 12th grade and went directly to Yale. Bill subsequent-ly received a PhD in Zoology from the University of Michigan, studying softshell turtles. Bill is Professor Emeritus of Pennsylvania State University thanks to a career spent entirely at that institution, teaching and doing research on the physio-logical ecology and ecotoxiciology of reptiles, amphibians and fish. Always curious about nature, Bill has dedicated his life to learning and sharing his knowledge with others. He has served on many advisory boards here in Southwest Florida to preserve the water that gives life to our region.

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The Little Shop of Horros - Carnivorous Plants

On a recent walk at Myakka State Forest I was pleased to come across a large patch of small butterworts, Pinguicula pumila, some of which were in bloom. The delicate bluish flowers are a delight, especially in the middle of "Winter." They are such small and inconspicuous plants that they are easy to overlook (see photo left). However they reveal something about the habitat that is beyond the tiny beauty of their form. They tell us that this particular patch of soil is very deficient in nutrients, which is not uncommon in some local pine flatwoods. The sandy soils are so deficient in nutrients that some plants respond by developing the ability to eat animals! Such tiny carnivorous gems obviously fail to live up to the fantasy of the "little shop of horrors" but nevertheless on a micro-scale that catch and devour small critters that stick to their leaves. A similar plant is the sundew (photo right) which is also commonly found locally in pine flatwoods. It is a bit more active in that it snares insects with sticky beads and envelops them with movements of its leaves. Another common carnivore is the usually yellow-flowered bladderwort, which is normally aquatic but equally a voracious eater of animal flesh. The benefit of this unusual feeding strategy for a plant is obvious- it obtains badly needed nutrients which are not available in the soil or water. Clear but deeply stained blackwaters of streams and lakes also reveal the essentially sterile nature of such habitats, due to the release of high concentrations of tannins from the plants.

The take-home story is that when you spot such carnivorous plants, you realize that life in this habitat is severely limited by nutrients, and that it would not be a good place to try and grow crops. Farmers in tropical forests along the Rio Negro in Brazil have found this out and now know that most of the nutrients are in the standing vegetation, not the soil. Thus after one cuts down the trees and removes them, what remains is a desert. We would do well to remember this for our own North American low-nutrient habitats which occur in many areas of both southeastern and northeastern forests.

So look down before you step, and watch for the tiny but beautiful carnivorous plants.

Bill Dunson
Englewood, FL & Galax, VA