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Project WILD Teacher Resource Guide
PiedmontPhysical Landscape The Piedmont covers about one third of the state of Georgia (18,100 square miles) and is typically associated with rough hilly terrain in the north and gentle rolling hills further south. The Piedmont extends south from the mountains of north Georgia to the fall line and ranges from 500-1,500 feet in elevation. The fall line marks the boundary between the crystalline rocks of the northern part of the state and the mostly unconsolidated sediments of the coastal plain. It is thought to be the furthest inland extent of the prehistoric coastline. The fall line is often associated with waterfalls and rapids formed as rivers tumble from the Piedmont to the coastal plain. Much of the Piedmont that early settlers found would have been
covered with broad-leaf hardwood trees dominated by the now rare
American Chestnut (Castanea dentata). Today much of
the Piedmont is covered with pine forests, a result of
silvicultural rather than natural processes. Like the Etowah River in north Georgia, the Flint River exhibits remarkable biotic diversity, exhibiting a particular abundance of freshwater mussel species. Freshwater mussels are unrelated to marine mussels and clams and are mostly members of the Unionoid family. The Flint originally was home to 29 mussel species, though recent surveys suggest that only 22 remain. Though certainly not the most charismatic and high profile species, our fresh water mussels have a fascinating natural history. Freshwater Mussels filter water through elaborate gill structures to collect oxygen and food. One of the most fascinating aspects of our freshwater mussels is their parasitic dependence upon fish for reproduction. Mussel larvae must attach to the gills of specific fish in order to survive. After several weeks, they drop off, and continue their development independently. In order to lure the required fish host within range, the adult mussels produce elaborate lures which look remarkably like the host fish. Once a suitable host approaches, the mussel expels the larvae (glochidia) into the water. This form of reproduction aids in mobility of an otherwise immobile species. Sedimentation, dams, pollution and channelization threaten many species of Unionoid mussels today.
Rainwater falling on rock outcrops fill pools of standing water. These pools are called solution pits and provide habitat for rare plants and animals. If rainfall is consistent these wet depressions support dish gardens, a unique rock outcrop community that exhibits distinctive rings of progressively drier habitat further from the wet center. Standing water in the center of a dish garden may contain Fairy Shrimp (Branchinella sp.) and Mat-forming Quillwort (Isoetes tegetiformans), species that only occur on rock outcrop pools. Both species can survive desiccation as the outcrop pools often dry up in summer. Because of their harsh exposed environment, rock outcrops offer a good place to observe primary succession and early soil development. The first organisms that can survive on the bare rock surface are lichens and mosses. These organisms actually dissolve rock with weak acids. After many years, through chemical and physical decomposition, a thin soil layer is formed. Soil allows other tolerant plants to establish, such as Diamorpha and Sedum, both succulent plants (fleshy leaves that hold moisture) well designed to withstand long periods of dry weather. As the soil continues to thicken, Broomsedge (Angropogon sp.), Sandworts (Caryophyllacea sp.) and Orange grass (Ctenium aromaticum) can colonize the rock. Confederate Daisy (Viguiera porteri), an endangered and endemic species, is quick to follow. Eventually small shrubs and trees will entirely cover the rock outcrop. This entire progression from rock to forest can often be seen on a single rock outcrop transect starting on bare rock and walking towards the encroaching forest at the outcrops edge. Rock outcrop plants are vulnerable to disturbance of vehicle and even extensive foot traffic. Many of the rock outcrops in Georgia are or have been actively quarried for granite, making Georgia the worlds largest granite producer. Key Species: Birds of Prey Our diurnal birds of prey (those that hunt by day), include the hawks, eagles, falcons, harriers and osprey. Our only nocturnal birds of prey are the owls. In Georgia we have three breeding species of owl and several others that winter sporadically throughout the state. Owls eyes see only in black and white but are extremely sensitive to low light conditions, allowing them to fly through the woods chasing prey in the middle of the night. Owls hearing is particularly acute, allowing them to pinpoint the location of their prey before they can even see it. Owls are also well known for their ability to fly almost completely silently, allowing them to sneak up on their prey without being detected. Outcrop Sites to Visit: Heggies Rock - Columbia County - 11 endemic species and 21 species
that are characteristic of rock outcrops. Nature Conservancy (404)
873-6946 Piedmont Sites to Visit: Project WILD Activities: 
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