Saturday, September 20, 2008
Litte River Canyon: Lynn Overlook: There's something exciting about plants that have to deal with adversity!
The Little River flows its entire length on top of Lookout Mountain; the rock of the falls and the exposed cliffs is a Pennsylvanian sandstone of the Pottsville Formation that overlays a thicker limestone sequence. Sandstone is a rock much more resistant to weathering (both physical and chemical) than limestone . Most waterfalls are sandstone, lots of cliffs are sandstone, and most arches are sandstone. The road here actually splits around a peculiar erosional formation, "Mushroom Rock."
The area around Lynn Overlook includes one of my favorite types of plant communities.The plants subsist on thin soil, gravel, or on the sandstone itself. They are tough xerophytes, mostly small by nature, further dwarfed by circumstance. Opuntia, talinum, schizachyrium, liatris, senecio, mosses, lichens among others, produce a tapestry of texture and subtle color whose effect was only enhanced by the early morning light. The overall appearance and the plants themselves were similar to what we had seen on the dolomite glades farther south but these on Lookout Mountain were not limited to species able to deal with levels of magnesium that would be toxic to most plants.
We wandered down a trail and across the road and encountered yet another wonderful plant association; the topography was such that enough water accumulated to allow the growth of Sphagnum, Polygala, Gerardia, and a vaiety of wetland species. As ususal we didn't locate the pitcher plants. I think I could spend the rest of my life studying the plants on an acre or two here. Wow.
Posted by ChrisU at 10:34 AM