Ridge and Valley Province

Physical Landscape
The Ridge and Valley province is adjacent to the Cumberland Plateau in northwestern Georgia and occupies about 2,800 square miles, or 5% of the states surface area.  The underlying rock is symmetrically folded, producing long parallel valleys and ridges that are oriented in a northeast-southwest direction.  The ridges typically reach 1,000-1,600 feet in elevation, while the valleys range from 600-800 feet.

The Chickamauga Valley and the Great Valley are separated by the Armuchee Ridges.  These three features form the majority of Georgias Ridge and Valley province.  The Great Valley runs north -south between Atlanta and Chattanooga.  During the Civil War this valley was a major corridor for troop movements for both the Union and Confederate armies.

The Coosa River Basin, which drains the central valley, is one of Georgias most diverse rivers.  It has been called the snail capital of the world, as 82 gastropods make it their home.

Habitat Highlight: Etowah River
Georgias rivers are the most diverse temperate freshwater ecosystems in the world.  Between native fish, mussels, snails and crayfish, our rivers are unparalleled for their species diversity.  Even freshwater turtle diversity in Georgia and Alabama is among the highest in the world.

The Etowah River offers a good example of a highly diverse Georgia river.  The Etowah watershed is located in central north Georgia and drains into Lake Allatoona in Cherokee County.  The headwaters of the Etowah are in the Blue Ridge province, but it flows though the Ridge and Valley.  Though small in comparison to many other river basins in Georgia, the Etowah river system is one of the most diverse in the world.  Unfortunately, it is also one of the most imperiled.  Historically, 91 species of fish were found in the Etowah.  Since the late 1800s however, 15 species have disappeared from the watershed.  Still, with 76 native fish species, the Etowah is one of the most biologically diverse river systems in the world, rivaling and surpassing many far larger systems.  For example, the Etowah is home to more that three times the native fish species than the entire Colorado River system, and more than twice that of the Columbia River System.  

Key Plants and Animals
Biologically the Ridge and Valley province is more similar to southwest Georgia than it is to the rest of north Georgia.  The Great Valley (Coosa River Valley) seems to act like a corridor running diagonally from northwest Georgia, southwest through Alabama, allowing species more typical of the Coastal Plain to expand their ranges into north Georgia.  A number of coastal plain species reach up the Coosa Valley into north Georgia, some continuously and others with disjunct populations.  Pine Woods Tree Frog (Hyla femoralis), Gopher Frog (Rana areolata), Southern Hognose Snake (Heterodon simus), as well as Chicken Turtle (Deirochelys reticularia), Squirrel Tree Frog (Hyla squirella) and Oak Toad (Bufo quercicus) extend north of the coastal plain only up the Coosa River Valley.

Species Highlight: Burrowing Crayfish
Georgia is home to about 70 species of crayfishes.  Of those 70 approximately 25 are classified as burrowing crayfishes.  Instead of living in open waters such as streams and lakes, these species construct complex burrows in which they spend most of their lives.  They are still aquatic animals however, and require water for survival.  They accomplish this by digging down until they reach groundwater.  These burrowing species typically are found in low swampy areas or along stream margins where the water table is close to the surface.  Small earthen chimneys are often the only evidence of their presence.  These chimneys are formed as they push small balls of earth out of their burrows, which can be more than 10 feet deep.  They can occasionally be seen foraging around the mouth of their burrow or moving over land on warm, damp nights, possibly looking for mates.

The Conasauga Blue Burrower (Cambarus cymatilis) is a burrowing crayfish known only from the Conasauga River system in northwestern Georgia.  This species was first found in burrows in the rose garden of a family in Chatsworth, Georgia.  It has since been found at only four additional locations.  The Conasauga Blue Burrower lives in complex systems of tunnels that it excavates and maintains throughout its life.  Because crayfish are aquatic organisms, at least one of these tunnels must go below the water table.  This animal is a beautiful blue color with creamy white edges on its claws and legs.

Other Key Species:
Cherokee Darter (Etheostoma scotti)
Etowah Darter (Etheostoma etowahae)
Upland combshell (Epioblasma metastriata)
Southern Clubshell (Pleurobema decisum)
Large-flowered Skullcap (Scuttelaria sp.)
Tennessee yellow-eyed grass (Xyris sp.)

Sites to Visit:
New Echota Historic Site Calhoun (800) 864-7275
Chickamauga and Chattanooga Nat. Military Park Fort Oglethorpe (706) 866-9241
Johns Mountain WMA Calhoun (770) 297-3000

Project WILD Aquatic Activities:
Fashion a Fish
Riparian Zone