If you drop a ball on the ground in this part of Georgia, you’ll have to chase it. If there is a naturally level patch of ground in this area, I haven’t seen it.
They call this the piedmont. The bigger mountains — the Appalachian Plateau and the Blue Ridge — are to the north. Most of Georgia is coastal plain.
The big change occurs at the fall line, where the ancient igneous and metamorphic rock formations rise out what was once an ancient sea. The fall line was once the shoreline.
If you look at a map, the fall line runs from Columbus, Macon and Augusta. The land rises for about 20 miles. It’s a good place for waterfalls. In the old days, merchants could bring big boats up the rivers to the fall line. If you wanted to ship goods further north, you usually had to reload the freight onto smaller boats above the falls.
Stone Mountain, billed inaccurately as the largest exposed mass of granite in the country, is a couple of miles from our house. It’s an indication of what lies below the soil here, a stark contrast to the deep layers of sediment south of the fall line.
The geologists say the Appalachians rose 500 million years ago, and it’s been eons since what’s now the Gulf of Mexico was at the fall line. Since then, the rocky formations have weathered, and so the naturalists here use a word I didn’t hear much in Texas: saprolite. It’s the decomposed rock that lies on the surface, Georgia’s famous red clay.
As you’d expect, it’s got plenty of iron oxides. But it also has quartz, silicon and aluminum. I wonder whether those nutrients allow different kinds of microbes to work at decomposing the dead vegetation on the forest floor. But I’m getting ahead of myself.
For now, the red clay of Georgia looks like the red dirt of East Texas to me.
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