The Okefenokee Swamp

Monday, April 27, 2009
Stephen Foster State Park (GA)
in the Okefenokee Swamp

Back a few years, when I was a kid, every once in a while you'd hear something about the Okefenokee Swamp. Usually what you heard left you with the impression that it was big, far away, remote, and something to be feared. There, huge beasts ruled and if someone were foolish enough to venture out into it they had better be prepared for trouble. There were herds of huge alligators, nests of even bigger snakes, big bears, and insects that could, and have, carried off small dogs. A run-in with any of these was surely fatal, or worse. There were moderating influences to our impression of the Okefenokee as well. For example, the kindly characters of the comic strip Pogo lived in the Okefenokee Swamp, and they seemed to like it.

But explorers, especially intrepid explorers, aren't daunted by things like 'gators or snakes or other dangers. No way. The Okefenokee is an important historical part of the America we're on a quest to see. Our Prime Directive requires that we explore places like it. So when we discovered that there's a Georgia State Park out in the middle of the Okefenokee there wasn't much more than brief glance at each other before we knew we had to go there... spend some time there. This is something that must be seen and experienced.

The Swamp is big, about half the size of Rhode Island, over 700 square miles. Many millenia ago the ocean covered this part of what is now Georgia and North Florida. As oceans tend to do, it deposited large sand-bars in various places. When the ocean receded these sand-bars became ridges that formed a kind of bowl that held any water within it. Contrary to what many people think, this "bowl" isn't a low spot in the surrounding geography like many swamps and marshes. No, this "bowl" is elevated above the level of the land around it. No significant streams flow into the Swamp. But two large rivers do flow out -- the Suwanee River (the one made famous by Stephen Foster), which drains most of the Swamp's area and eventually flows into the Gulf of Mexico, and the St. Mary's River which drains the Southeastern corner of the Swamp and flows into the Atlantic Ocean near Jacksonville. The source of almost all the water in the Swamp is the rain that falls into it.

The word "Okefenokee" derives from an Indian word that means "trembling earth", a reference to it's spongy bogs. The bottom of the Swamp consist of thick layers of decomposing plant material. During the long process of decomposition this material becomes what we call peat. Often, in the layers of peat, methane gas given off by the process causes the layers to separate. The gas is lighter than air and can cause the upper portion from this separation to float to the surface. These are called "blow-ups" or "batteries" that can be thought of as small floating islands. After a period of time grasses and other plants take root and the blow-up grows into a bog which becomes more supportive of even larger plants. It's possible to walk on these bogs... each step causing the ground to give as it struggles to support your weight... and thus, trembling. If the bog survives long enough, eventually trees will sprout and the roots will anchor the island to the sandy bottom of the Swamp, immobilizing it and making it a more traditional island... one that stays in one place.

The Okefenokee is a blackwater swamp -- the largest in the USA. The decaying matter that comes from this particular mix of trees and plants is particularly high in tannic acid. During the process of decomposing these tannins stain the water a dark reddish brown, almost black -- thus the term blackwater. Also because of the high tannin content, the water is very acidic (typical ph of 3.5 to 3.7) which influences the mix of plants and animals that can live in this acidy environment. It's a stable ecosystem that has evolved over time to be what it is today.

Despite the term blackwater, the water doesn't look at all dirty or murky or silty. It's clear but just very dark reddish black, like coffee or a dark reddish tea. During the early days of ships crossing the Atlantic this water was collected and barreled, to be used as drinking water during long voyages. This high acid content kept the water "fresh" much longer than other normal water that could quickly become foul and undrinkable.

The Western part of the Okefenokee Swamp, where we were mostly, is more heavily wooded. The Eastern part is largely open prairie wetlands. Fire is an integral part of life in the Okefenokee and life has adapted to regular dry spells and burns of the underbrush. As recently as 2007 more than 75% of the park burned during a prolonged drought. As long as the fire isn't so intense that it gets into the crown of the trees, they'll survive. We saw a large area just outside the State Park that was control-burned just a month ago and observed a large amount of new growth already sprouting under a surviving canopy of tall pines. The floor of the woods was already completely green.

During the late 19th and early 20th centuries there was no shortage of people who saw $$ dollar-signs in all those magnificent trees and rich land if only something could be done to get rid of that dang water. Canals were dug, logging and milling operations established, railroads built, and people brought in to make it all happen. They all eventually failed but not before much of the virgin old-growth cypress and pine trees were cut and turned into roofing shakes and turpentine. The Swamp slowly, surely, swallowed up these operations and they were consumed by the costs of dealing with all the water and the harsh environment. It's tough to fight mother nature.

T