Upland Forests and Woodlands
Mesic Forests: Mesic (evenly moist, very rarely dry) hardwood forests grow in cool, protected sites where soils are deep and rich, such as valley floors, ravines, north-facing coves, and the bottoms of some large sinkholes. This natural community most often occurs on limestone-based soils.
Indicator species: tulip-tree, southern sugar maple, basswood, yellow buckeye, Ohio buckeye, white ash, and American beech.
What's special: these forests can be lush and beautiful, especially in the spring, when a rich diversity of spring wildflowers that are uncommon elsewhere bloom here, including celandine poppy, Virginia bluebells, bent trillium, and fern-leaf phacelia. The rich litter of the forest floor supports many amphibians and snails.
Related communities: Calcareous cliffs are sometimes embedded within this community, and Bottomlands and Floodplains may intergrade with this community near streams and rivers.
Dry Calcareous Forests: These forests grow over dry to somewhat dry soils, and include both calcareous and sub-calcareous conditions on valley floors or lower slopes. Rocky outcroppings appear occasionally.
Indicator species: calcium-loving species, such as Chinquapin oak, Shumard oak, chalk maple, eastern red cedar, redbud, Carolina buckthorn, coralberry, fragrant sumac, white ash, and redbud,
What's special: In Georgia, these expanses of calcareous forests and the species that grow on them are rare because fairly acidic soils are most common.
Related communities: as trees become sparse and soils are rocky, this community can grade into calcareous (cedar glades). As soils become more acidic, this community will grade into the Acidic Oak-Pine-Hickory Forest.
Acidic Oak-Pine Forests: Hardwood forests, often mixed with pine, on sandy, rocky, acidic, somewhat dry to very dry sites on the sandstone and conglomerate ridge tops and on some shale slopes.
Indicator species: Rock chestnut oak, white oak, southern red oak, black oak, scarlet oak, shortleaf pine, virginia pine, black gum and mountain laurel.
Related communities: As fire is increased, this community will grade into Pine-Oak woodlands. Acidic glades are sometimes embedded within this communities.
Pine-Oak Woodlands: Woodlands are sunnier than forests: gaps in the canopy that let roughly 20- 80% of all sunlight in to the forest floor. Pines and dry-site oaks dominate. Usually the shrub layer is sparse, sometimes allowing a lush ground cover to develop. Woodlands often grow on sites that are too dry to support a closed canopy, such as on sharp ridges or south-facing slopes with stony, thin soils. They are most common on sandstone ridges with acidic soils. They also grow on moister sites where fire keeps the site open and as a mid-successional phase as vegetation begins growing back after a site was cleared.
Indicator species: Virginia pine, shortleaf pine, rock chestnut oak
What's special: The combination of trees and, often, the lush ground cover allowed by the sunlight reaching the forest floor creates many different habitats for wildlife, adding plant and animal diversity to the landscape.
Related Communities: As the tree cover gets more dense, this community grades into Oak Forest. As it gets thinner, the site will grade into the Acidic Glades and Barrens community.
Montane Longleaf Woodlands: Longleaf pine anywhere in the landscape indicates that the site is or could be a longleaf pine community. If the site is dominated or co-dominated by longleaf pine, it is a montane longleaf woodland. These woodlands grow on steep, southfacing, very dry slopes that experienced fire fairly frequently.
What's special: Montane longleaf pine communities are very rare in Georgia. These woodlands are treasured because, like other woodlands, the combination of trees and a lush ground cover provide a great diversity of plant and animal life. Longleaf is superbly adapted to fire, and is habitat for the rare red-cockaded woodpecker.
Common trees: Longleaf pine, loblolly pine and dry site oaks such as post oak, blackjack oak, and rock chestnut oak. In some cases, sites are being restored to longleaf pine only.
Related communities: Montane longleaf communities are closely related to Pine-Oak Woodlands and have many species and ecolgociatl characteristics in common with them. If no fires occur, this community will gradually succeed to an Oak-Pine Forest.
Open Communities: Prairies, Glades, Barrens, Cliffs, Bluffs, and Rock Outcrops
Calcareous Prairies and Barrens: (also called Coosa Prairies or Floyd County Prairies) Calcareous prairies and barrens are a mosaic of prairies and barrens that grow over calcareous bedrock in Floyd County, Georgia, in the Coosa River watershed. This natural community is made up of expanses of grasses and forbs (non-woody plants). Praires occur on thicker soils, and grade into barrens as the soils get thinner and more gravelly. The soils may be wet or dry, with different plant assemblages depending upon the moisture levels.
What's special: This natural community is very rare in Georgia and ecologically significant. There is great diversity, with many rare species, including some that are rare, with very narrow growing ranges. Two critically imperiled plant assemblages grow here. There are many affinities with the praries growing farther west. The praries are especially beautiful in June, as seen in the picture to the left, when the coneflowers are blooming, and again in the fall, when many other composites bloom. Prairie plants attract vast numbers of pollinators and insects that graze upon and find refuge within them. They are also are habitat for many birds and small mammals, which feed upon the insects, and nest or breed under cover of the dense vegetation.
Related to: As soils become thinner, this community will grade into the Calcareous Glades and Barrens natural community. Wetter, thicker soils without fire will host the Flatwoods natural community.
Acidic Glades and Barrens: These glades and barrens occur on sandstone and conglomerate on the ridgetops of the ecoregion. They consist of a mosaic of fairly flat rock outcroppings, barrens with shallow, gravelly, acidic soils, and virginia pine woodlands.
Indicator species: Virginia pine, mountain laurel, black gum, little bluestem, big bluestem, oat grasses.
What's special: these openings support grasses and composites that are not found in surrounding forests, increasing the diversity of plant and animal species. In addition, the outcroppings can be beautiful, with turtlebacks, lichen-encrusted sandstone, and picturesque formations.
Related communities: This community overlaps the Acidic Cliffs and Outcrops community, in that there is no clear line between a tall, cliff-like rock and one that is flat enough to be glade-like. This community also occurs near cliff edges and as openings in Pine-Oak Woodlands, and grades imperceptibly into both communities.
Calcareous Glades and Barrens (Cedar Glades): These are rocky, non-forested areas that have many limestone outcroppings and expanses of shallow, gravelly soils. The vegetation is usually a mosaic of herbaceous areas, shrubs, bare rock, and widely spaced, stunted trees. Eastern red cedar is very common, so these communities are often called Cedar Glades.
Indicator species: eastern red cedar in the midst of flat outcroppings of limestone.
What's special: Expanses of exposed limestone are rare in Georgia and so the environments hosts a number of rare, endemic species, including least glade cress, purple tassels, Nashville breadroot, and Eggleston's violet, as well as species that are more common farther west. These glades and barrens thus contribute to the biological diversity of the ecoregion.
Related to: This natural community grades into dry calcareous forest as soil deepens over the limestone substrate and if fire becomes less common. This community also overlaps strongly with the Calcareous Prairies natural community; however, the prairies will have more extensive areas of deeper soil, and fewer exposed limestone outcroppings.
Acidic Cliffs and Outcrops: Acidic cliffs and rock outcrops are steep to vertical outcroppings of acidic rock, usually sandstone, although mid-slope acidic shale outcroppings also occur. Some large rock outcrops are also included in this community, Moisture levels range from xeric to seasonally wet near waterfalls.
What's special: This natural community is most dramatic along the upper rim of the Plateau Escarpment sub-ecoregion, where it forms steep, spectacular cliffs as shown in the photo at left. In some places, such as Rock Town and Zahn Tract, a series of house-sized outcrops create "towns" or "cities" with narrow alley-ways between the rocks. The rocks can weather to beautiful shapes.
Related communities: This community is very closely related to Acidic Glades and Barrens and intergrades with it.
Acidic Seepage Wetlands: Seepage wetland form in shallow swales, in depressions, and near streamheads, usually on the sandstone caps of ridges and plateaus, although they can also be found seeping from shale in some places. They occur where water flows slowly out of joints, or at the base of steep slopes.
Indicator species: royal fern, cinnamon fern, jack-in-the-pulpit, soapwort gentian, southern wild raisin.
What's special: Often these communities are openings in forests, where the swaths of ferns form a lush contrast to the drier forests they're embedded within Where fire is more common, seeps can be sunny, with an array of wildflowers, including the beautiful monkey-face orchid. These wetlands are important for amphibians.
Bottomlands, Floodplains, and Riparian Zones: This natural community includes:
1) Bottomland Forest: flat, low-lying areas that are not directly next to the river channel. They are close to the water table and occasionally to often flooded. Some high areas, and those at the edge of the flood zone grade into the Mesic Forest Natural Community. Often there are Seepage Wetland Natural Communities embedded in the bottomlands.
2) Riparian zone - the strip next to the river. It is flooded often with the strongest flood waters. There is more sun, with many shrubs and non-woody plants, and a few trees. This includes a special "stream scour" community, which forms chute-like areas in sandstone, as shown at right, with Virginia spiraea.
Indicator species include river birch, box elder, green ash, and sycamore.
What's special: this natural community is one of lush vegetation and a variety of habitats that support a large diversity of animals.
Related communities: Some high areas in the bottomland forest, and those farthest from the flood zone grade into the Mesic Forest Natural Community; plants such as trilliums, mayapples, and trout lilies are good indicators. Often there are Seepage Wetland Natural Communities embedded in the bottomlands. Beaver ponds are a part of the river channel, and are often included within this co