**Georgia Ecoregion Descriptions**

**August, 2001**

**45. Piedmont**

Considered the nonmountainous portion of the old Appalachians Highland
by physiographers, the northeast-southwest trending Piedmont ecoregion
comprises a transitional area between the mostly mountainous ecoregions
of the Appalachians to the northwest and the relatively flat coastal
plain to the southeast. It is a complex mosaic of Precambrian and
Paleozoic metamorphic and igneous rocks with moderately dissected
irregular plains and some hills. The soils tend to be finer-textured
than in coastal plain regions. Once largely cultivated, much of this
region has reverted to pine and hardwood woodlands, and, more recently,
spreading urban- and suburbanization.

45a. The **Southern Inner Piedmont** is mostly higher in elevation with
more relief than 45b, but is generally lower and has less relief and
contains different rocks and soils than 45d. The rolling to hilly,
well-dissected upland contains mostly schist, gneiss, and granite
bedrock. In the western portion, west of Atlanta and into Alabama, mica
schist and micaceous saprolite are typical. To the east, biotite gneiss
is more common. The region is now mostly forested, with major forest
types of oak-pine and oak-hickory, with less loblolly-shortleaf pine
forest than 45b. Open areas are mostly in pasture, although there are
some small areas of cropland. Hay, cattle, and poultry are the main
agricultural products. In Georgia, urban/suburban land cover has
increased greatly within this ecoregion over the past twenty years.

45b. The **Southern Outer Piedmont** ecoregion has lower elevations,
less relief, and less precipitation than 45a. Loblolly-shortleaf pine is
the major forest type, with less oak-hickory and oak-pine than in 45a.
Gneiss, schist and granite are the dominant rock types, covered with
deep saprolite and mostly red, clayey subsoils. The majority of soils
are Kanhapludults. The southern boundary of the ecoregion occurs at the
Fall Line, where unconsolidated coastal plain sediments are deposited
over the Piedmont metamorphic and igneous rocks.

45c. The **Carolina Slate Belt** is found primarily in the Carolinas,
although a small area extends into Georgia. The mineral-rich
metavolcanic and metasedimentary rocks with slatey cleavage are
finer-grained and less metamorphosed than most Piedmont regions. It
tends to be less rugged, less dissected, with wider valleys than other
Piedmont areas, and it generally has more silty and silty clay soils.

45d. The **Talladega Upland** of the Georgia Piedmont contains some
dissected hills and tablelands that are mostly forested and at generally
higher elevations than 45a and 45b. The geology is distinctive,
consisting of mostly phyllite, quartzite, slate, metasiltstone, and
metaconglomerate, in contrast to the high-grade metamorphic and
intrusive igneous rocks of 45a and 45b. To the west in Alabama are more
mountainous parts of the region, including Alabama's highest peak,
2407-foot Cheaha Mountain. The climate of 45d is slightly cooler and
wetter than the other ecoregions (45a, b, c) of the Georgia Piedmont.
Oak-hickory-pine is the natural vegetation type.

45h. The **Pine Mountain Ridges**, a small, narrow region in the
southwest portion of the Georgia Piedmont, contains quartzite-capped,
steep-sloped ridges that rise 300-400 feet above the Piedmont surface to
elevations over 1300 feet. Pine Mountain and Oak Mountain are the
primary linear ridges trending southwest to northeast, and several other
smaller ridges and mountains between these, including Bull Trail
Mountain, Indian Grave Mountain, Salter Mountain, and Huckleberry
Pinnacle, add to the region's more mountainous appearance. The Flint
River has cut some narrow, steep gorges, 400 feet deep, through the
ridges. Streams in this region are often of higher gradient than
surrounding areas of 45b, and contain more rocky and gravelly
substrates.

**65. Southeastern Plains**

These irregular plains with broad interstream areas have a mosaic of
cropland, pasture, woodland, and forest. Natural vegetation is mostly
oak-hickory-pine and Southern mixed forest. The Cretaceous or
Tertiary-age sands, silts, and clays of the region contrast geologically
with the Paleozoic limestone, shale and sandstone of ecoregions 67 and
68, or with the even older metamorphic and igneous rocks of the Piedmont
(45). Elevations and relief are greater than in the Southern Coastal
Plain (75), but generally less than in much of the Piedmont. Streams in
this area are relatively low-gradient and sandy-bottomed.

65c. The **Sand Hills** of Georgia form a narrow, rolling to hilly,
highly dissected coastal plain belt stretching across the state from
Augusta to Columbus. The region is composed primarily of Cretaceous and
some Eocene-age marine sands and clays deposited over the crystalline
and metamorphic rocks of the Piedmont (45). Many of the droughty,
low-nutrient soils formed in thick beds of sand, although soils in some
areas contain more loamy and clayey horizons. On the drier sites, turkey
oak and longleaf pine are dominant, while shortleaf-loblolly pine
forests and other oak-pine forests are common throughout the region.

65d. The dissected irregular plains and gently rolling low hills of the
**Southern Hilly Gulf Coastal Plain** ecoregion developed over diverse
bands of sand, clay, and marl formations. The heterogeneous region that
stretches west across Alabama and into Mississippi, has a mix of clayey,
loamy, and sandy soils. It has more rolling topography, higher
elevations, and more relief than 65g and 65k, and streams have increased
gradient. The natural vegetation is mostly oak-hickory-pine forest, and
to the south begins a transition into southern mixed forest. Land cover
is mostly mixed forest and woodland, pine plantations, with some small
areas of pasture and cropland.

65g. The **Dougherty Plain** is mostly flat to gently rolling and
influenced by the near-surface limestone. The karst topography contains
sinkholes, springs, and fewer streams in the flatter part of the plain.
The northwestern boundary is gradational, as more gentle slopes and
lower relief are found towards the center of the region. On the
southeast, the Pelham escarpment marks the boundary with the Tifton
Upland (65h). Landcover is primarily cropland and pasture, with some
small areas of mixed forest. Crops such as peanuts and pecans are
common, and cotton production has increased dramatically in recent
years. Natural forest cover consisted of pines, including longleaf pine,
red oaks, and hickories. Many shallow, flat-bottomed depressions are
scattered throughout the region, caused by solution of the underlying
limestone. The wetter, poorly drained depressions contain blackgum,
sweetgum, water oak, and a few pines and cypress. Many of the limesink
ponds and marshes act as biological oases in the mostly agricultural
landscape.

65h. The **Tifton Upland** of Georgia has more rolling, hilly topography
compared to 65g and 75e, with a mosaic of agriculture, pasture, and some
mixed pine/hardwood forests. Soils are well-drained, brownish, and
loamy, often with iron-rich or plinthic layers. They support crops of
cotton, peanuts, soybeans, and corn. On the west side of the region, the
Pelham Escarpment has bluffs and deep ravines with cool microclimates
that support several rare plants and animals, as well as species with
more northern affinities.

65k. In contrast to the more forested Sand Hills (65c) that formed
mostly on light-colored Cretaceous sands, the **Coastal Plain Red
Uplands** formed on reddish Eocene sand and clay formations. Soils are
mostly well-drained with a brown or reddish brown loamy or sandy surface
layer and red subsoils. The majority of the area is in cropland or
pasture, with some woodland on steeper slopes. The Fort Valley Plateau
falls within this ecoregion, a relatively small agricultural area with
less relief, flat-topped interfluves, and less dissection than other
parts of the 65k.

65l. Also called the Vidalia Upland in Georgia, the **Atlantic Southern
Loam Plains** ecoregion is generally lower, flatter, and more gently
rolling than 65k, and has more cropland and finer-textured soils than
75f. Similar to 65h, it has an abundance of the agriculturally important
Tifton soils, but the region also contains forested areas that are more
sloping or are low, flat and poorly drained. Parallel to some of the
major stream courses are some excessively-drained, dunal sand ridges
with xeric vegetation such as longleaf pine / turkey oak forests, and
some distinctive evergreen shrubs, such as rosemary and woody mints.

65o. The **Tallahassee Hills/Valdosta Limesink** ecoregion combines two
slightly different areas, both influenced by underlying limestone. The
Floridan aquifer is thinly confined in this region, and streams are
often intermittent or in parts flow underground in the karst landscape.
In the west, the Tallahassee Hills portion has rolling, hilly topography
that is more forested than 65h. Clayey sands weathered to a thick red
residual soil are typical. Relief decreases towards the east, and the
Valdosta Limesink area has more solution basins with ponds, lakes, and
swampy depressions, as well as areas with more cropland. The soils are
typically brownish. Mixed hardwoods and pine are found on the clayhill
upland soils, while longleaf pine/xerophytic oak types occur on the
sandy, well-drained areas.

65p. **Southeastern Floodplains and Low Terraces** comprise a riverine
ecoregion of large sluggish rivers and backwaters with ponds, swamps,
and oxbow lakes. River swamp forests of bald cypress and water tupelo
and oak-dominated bottomland hardwood forests provide important wildlife
corridors and habitat. The Georgia portion of the region includes the
major river systems, such as the Chattahoochee, Flint, Ocmulgee, Oconee,
Ogeechee, and Savannah. All of these alluvial rivers of 65p either
originate in or cross the Piedmont (45).

**66. Blue Ridge**

The Blue Ridge extends from southern Pennsylvania to northern Georgia,
varying from narrow ridges to hilly plateaus to more massive mountainous
areas with high peaks. The mostly forested slopes, high-gradient, cool,
clear streams, and rugged terrain occur on a mix of igneous,
metamorphic, and sedimentary geology. Annual precipitation of over 80
inches can occur on the well-exposed high peaks. The southern Blue Ridge
is one of the richest centers of biodiversity in the eastern U.S. It is
one of the most floristically diverse ecoregions, and includes
Appalachian oak forests, northern hardwoods, and, at the highest
elevations in Tennessee and North Carolina, Southeastern spruce-fir
forests. Shrub, grass, and heath balds, hemlock, cove hardwoods, and
oak-pine communities are also significant. Black bear, whitetail deer,
wild boar, turkey, grouse, songbirds, many species of amphibians and
reptiles, thousands of species of invertebrates, and a variety of small
mammals are found here.

66d. The **Southern Crystalline Ridges and Mountains** contain the
highest and wettest mountains in Georgia. These occur primarily on
Precambrian-age igneous and high-grade metamorphic rocks. The common
crystalline rock types include gneiss, schist, and quartzite, covered by
well-drained, acidic, brownish, loamy soils. Some mafic and ultramafic
rocks also occur here, producing more basic soils. Elevations of this
rough, dissected region are typically 1800-4000 feet, with Brasstown
Bald Mountain, the highest point in Georgia, reaching 4,784 feet.
Although there are a few small areas of pasture and apple orchards, the
region is mostly forested.

66g. **The Southern Metasedimentary Mountains** in Georgia contain rocks
that are generally not as strongly metamorphosed as the gneisses and
schists of 66d. The geologic materials are mostly late Pre-Cambrian and
include slate, conglomerate, phyllite, metagraywacke, metasiltstone,
metasandstone, and quartzite, with some schist and gneiss. Although the
highest peaks are lower than in 66d, and parts of the region have more
open low hills, there are some isolated masses of rugged mountains, such
as the biologically-diverse Cohutta Mountains, Rich Mountains, and Fort
Mountain.

66j. The **Broad Basins** ecoregion is drier, and has lower elevations
and less relief than the more mountainous Blue Ridge regions (66g, 66d).
It also has less bouldery colluvium than those two surrounding regions
and more saprolite. The soils are mostly deep, well-drained, loamy to
clayey Ultisols. Although this rolling foothills region is mostly
forested, it has more pasture than adjacent regions, and some narrow
areas of row crops and truck crops on terraces and floodplains. Much of
the pasture and corn crops support local cattle, hog, or poultry
operations.

**67. Ridge and Valley**

Sometimes called the Great Valley in Georgia, this is a relatively
low-lying region between the Blue Ridge (66) to the east and the
Southwestern Appalachians (68) on the west. As a result of extreme
folding and faulting events, the roughly parallel ridges and valleys
come in a variety of widths, heights, and geologic materials, including
limestone, dolomite, shale, siltstone, sandstone, chert, mudstone, and
marble. Springs and caves are relatively numerous. Land cover is mixed
and present-day forests cover about 50% of the region. Forested ridges,
and valleys with pasture and cropland, are typical in many parts of
ecoregion 67. Its diverse habitats contain many unique species of
terrestrial and aquatic flora and fauna.

67f. The **Southern Limestone/Dolomite Valleys and Low Rolling Hills**
form a heterogeneous region composed predominantly of limestone and
cherty dolomite. Landforms are mostly undulating valleys and rounded
ridges and hills, with many caves and springs. Soils vary in their
productivity, and land cover includes oak-hickory and oak-pine forests,
pasture, intensive agriculture, and urban and industrial. Along the
Coosa River floodplain, biota more typical of coastal plain regions can
be found due to the valley and riverine connection to ecoregion 65 in
Alabama.

67g The **Southern Shale Valleys** consist of undulating to rolling
valleys and some low, rounded hills and knobs that are dominated by
shale. The soils formed in materials weathered from shale, shaly
limestone, and clayey sediments, and tend to be deep, acidic, moderately
well-drained, and slowly permeable. The steeper slopes are used for
pasture or have reverted to brush and mixed forest land. Small fields of
hay, corn, soybeans, tobacco, and garden crops are grown on the foot
slopes and bottom land.

67h. The **Southern Sandstone Ridges** region encompasses the major
sandstone ridges, but these ridges also have areas of shale, siltstone,
and conglomerate. The steep, forested ridges tend to have narrow crests,
and the soils are typically stony, sandy, and of low fertility. The
chemistry of streams flowing down the ridges can vary greatly depending
on the geologic material. In Georgia and Tennessee, most of the
sandstone ridges are relatively narrow, but in Alabama, the region also
includes the Coosa and Cahaba ridges that are broader and of younger
Pennsylvanian-age sandstone and shale. Oak-hickory-pine forests are the
dominant land cover.

67i. The **Southern Dissected Ridges and Knobs** contain more
crenulated, broken, or hummocky ridges, compared to the smoother, more
sharply crested sandstone ridges of 67h. Although shale is common, there
is a mixture and interbedding of geologic materials, including cherts,
siltstone, sandstone, and quartzose limestone. Oak forests and pine
forests are typical for the higher elevations of the ridges, with
oak-hickory and a number of more mesic forest species on the lower
slopes, knobs, and draws.

**68. Southwestern Appalachians**

Stretching from Kentucky to Alabama, these low mountains contain a
mosaic of forest and woodland with some cropland and pasture. The
eastern boundary of the ecoregion, along the abrupt escarpment next to
the Ridge and Valley (67), is relatively smooth and only slightly
notched by small eastward flowing stream drainages. The western
boundary, next to the Interior Plateau's Eastern Highland Rim in Alabama
and Tennessee, is more crenulated with a rougher escarpment that is more
deeply incised. The mixed mesophytic forest is restricted mostly to the
deeper ravines and escarpment slopes, and the summit or tableland
forests are dominated by mixed oaks with shortleaf pine.

68c. The **Plateau Escarpment** is characterized by steep, forested
slopes and high velocity, high gradient streams. Local relief is often
1000 feet or more. The geologic strata include Mississippian-age
limestone, sandstone, shale, and siltstone, and Pennsylvanian-age shale,
siltstone, sandstone, and conglomerate. Streams have cut down into the
limestone, but the gorge talus slopes are composed of colluvium with
huge angular, slabby blocks of sandstone. Vegetation community types in
the ravines and gorges include mixed oak and chestnut oak on the upper
slopes, more mesic forests on the middle and lower slopes (beech-yellow
poplar, sugar maple-basswood-ash-buckeye), with some rare hemlock along
rocky streamsides and river birch along floodplain terraces.

68d. The **Southern Table Plateaus** include Sand Mountain and Lookout
Mountain in northwest Georgia. While it has some similarities to the
Cumberland Plateau (68a) in Tennessee with its Pennsylvanian-age
sandstone caprock, shale layers, and coal-bearing strata, this ecoregion
is lower in elevation, has a slightly warmer climate, and has more
agriculture. Although the Georgia portion is mostly forested, primarily
with mixed oak and oak-hickory communities, elevations decrease to the
southwest in Alabama and there is more cropland and pasture. The plateau
surface is less dissected with lower relief compared to the the Plateau
Escarpment (68c), and it is slightly cooler with more precipitation than
in the nearby lower elevations of 67f .

**75. Southern Coastal Plain**

The Southern Coastal Plain extends from South Carolina and Georgia
through much of central Florida, and along the Gulf coast lowlands of
the Florida Panhandle, Alabama, and Mississippi. From a national
perspective, it appears to be mostly flat plains, but it is a
heterogeneous region also containing barrier islands, coastal lagoons,
marshes, and swampy lowlands along the Gulf and Atlantic coasts. In
Florida, an area of discontinuous highlands contains numerous lakes.
This ecoregion is generally lower in elevation with less relief and
wetter soils than ecoregion 65. Once covered by a variety of forest
communities that included trees of longleaf pine, slash pine, pond pine,
beech, sweetgum, southern magnolia, white oak, and laurel oak, land
cover in the region is now mostly slash and loblolly pine with
oak-gum-cypress forest in some low lying areas, citrus groves, pasture
for beef cattle, and urban.

75e. The **Okefenokee Plains** consist of flat plains and low terraces
developed on Pleistocene-Pliocene sands and gravels. These plains have
slightly higher elevations and less standing water than 75g, although
there are numereous swamps and bays. There are some highly acidic
softwater lakes, mostly with low clarity, darkly colored water, but the
color is variable depending on rainfall. Soils in the region are
somewhat-poorly to poorly drained. The region has mostly coniferous
forest and young pine plantation land cover, with areas of forested
wetland.

75f. The **Sea Island Flatwoods** are poorly-drained flat plains with
lower elevations and less dissection than 65l. Pleistocene sea levels
rose and fell several times creating different terraces and shoreline
deposits. Spodosols and other wet soils are common, although small areas
of better-drained soils add some ecological diversity. Trail Ridge is in
this region, forming the boundary with 75g. Loblolly and slash pine
plantations cover much of the region. Water oak, willow oak, sweetgum,
blackgum and cypress occur in wet areas.

75g. The **Okefenokee Swamp** is a mixture of forested swamp and
freshwater marsh with some pine uplands. With Trail Ridge at its eastern
boundary, the swamp drains to the south and southwest and contains the
headwaters for the St. Marys and Suwannee Rivers. The swamp contains
numerous islands, lakes, and thick beds of peat. The slow-moving waters
are tea-colored and acidic. Cypress, blackgum, and bay forests are
common, with scattered areas of prairie, which are comprised of grasses,
sedges, and various aquatic plants. The Okefenokee Swamp is a
rainfall-dependent system, and cycles of drought and fire affect both
its vegetation and wildlife distributions. Most of this region is within
the Okefenokee National Wildlife Refuge.

75h. The **Bacon Terraces** include several relatively flat, moderately
dissected terraces with subtle east-facing scarps. The terraces,
developed on Pliocene-Pleistocene sands and gravels, are dissected in a
dendritic pattern by much of the upper Satilla River basin. Cropland is
mostly on the well-drained soils on the long, narrow, flat to gently
sloping ridges paralleling many of the stream courses. The broad flats
of the interfluves are often poorly drained and covered in pine, while
bottomland forests are found in the wet, narrow floodplains.

75i. **Floodplains and Low Terraces** are a continuation of the riverine
65p ecoregion across the Southern Coastal Plain. The broad floodplains
and terraces of major rivers, such as the Savannah, Ogeechee, and
Altamaha, comprise the region. Composed of stream alluvium and terrace
deposits of sand, silt, clay, and gravel, along with some organic muck
and swamp deposits, the region includes large sluggish rivers and
backwaters with ponds, swamps, and oxbow lakes. River swamp forests of
bald cypress and water tupelo and oak-dominated bottomland hardwood
forests provide important wildlife habitat.

75j. The **Sea Islands/Coastal Marsh** region contains the lowest
elevations in Georgia and is a highly dynamic environment affected by
ocean wave, wind, and river action. Mostly sandy soils occur on the
barrier islands, while organic and clayey soils occur in the freshwater,
brackish, and salt marshes. Maritime forests of live oak, red cedar,
slash pine, and cabbage palmetto grow on parts of the sea islands, and
various species of cordgrass, saltgrass, and rushes are dominant in the
marshes. The coastal marshes, tidal creeks, and estuaries are important
nursery areas for fish, crabs, shrimp, and other marine species. Parts
of the region have a long history of human alterations. Native Americans
cultivated corn, melons, squash, and beans; a Spanish mission period
during the 1500-1600\'s included crops of citrus, figs, peaches, olives,
artichokes, and onions; and a plantation agriculture economy in the late
1700\'s through the 1800\'s produced indigo, rice, sugar cane, and sea
island cotton.