Natural Communities of North Georgia
  • Home
  • Piedmont
    • Piedmont Overview
    • Mesic (Moist) Forests
    • Oak-Pine-Hickory Forests
    • Bottomland/Floodplain Forest
    • Pine-Oak Woodlands
    • Montane Longleaf
    • Prairies and Savannas (Upland)
    • Wet Meadows and Marshes
    • Granite Outcrops
    • Glades, Barrens, and Woodlands
    • Ultramafic Barrens and Woodlands
    • Cliffs and Bluffs
    • Flatwoods (Upland Depression Swamps)
  • Blue Ridge
    • Blue Ridge Overview
    • Northern Hardwoods
    • Montane Oak Forests
    • Fertile Cove Forests
    • Acidic Cove Forests
    • Oak Forests
    • Pine-Oak Woodlands
    • High Elevation Outcrops
    • Mafic Dome Rock Outcrops
    • Rock Outcrops, Cliffs and Bluffs
    • Ultramafic Barrens and Woodlands
    • Mountain Bogs
    • Seepage Wetlands
    • Spray Cliffs
    • Montane Bottomlands and Flooplains
  • Cumberland Ridge & Valley
    • Cumberland Ridge & Valley Overview
    • Mesic Forests
    • Dry Calcareous Forests
    • Acidic Oak-Pine Forests
    • Pine-Oak Woodlands
    • Montane Longleaf
    • Calcareous (Cedar) Glades
    • Calcareous Cliffs
    • Calcareous Prairies and Barrens
    • Acidic Glades and Barrens
    • Acidic Cliffs and Outcrops
    • Flatwoods
    • Acidic Seepage Wetlands
    • Bottomlands and Flooplains
  • Impact of Rock Type on Plant Composition
  • Plant Adaptations to Deciduous Forests

Cumberland Plateau/Ridge & Valley Acidic Cliffs and Outcrops

Acidic cliffs and outcrops are steep, nearly vertical outcroppings of acidic rock, usually sandstone or conglomerate. These cliffs form the ecoregion's escarpment, rising starkly and looming dramatically over valley floors. Lichens and mosses are scattered picturesquely over the rock faces.  Vegetation, which is adapted to acidic conditions, is typically sparse and limited to crevices and ledges. Moisture levels range from extremely dry, creating harsh conditions to seepage areas where waterfalls flow during wetter periods. "Rockhouses", or caves, form at the base of the cliffs, where softer shales are being eroded from beneath the more resistant sandstone.

Indicator and representative species:  Dry crevices and shallow ledges provide footings for red maple, Virginia pine, black birch, rock chestnut oak, rhododendrons, sparkleberry, mountain laurel, fringe-tree, bush honeysuckle, Carolina jessamine, and numerous grasses and wildflowers. Moist cliffs support jack-in-the-pulpit, rock alumroot, early saxifrage, and poison ivy,
​What's special: These natural communities are very picturesque, due to the steep cliff faces, far-reaching views, and variable outcroppings formed from weathering and erosion.   In some places, such as Rock Town and Zahnd Tract, house-sized outcrops create "towns" with  narrow alley-ways between the rocks.  The rocks can weather to beautiful shapes. Catawba rhododendron blooms beautifully in mid-spring.
Related communities:
 
This community is very closely related to and intergrades with Acidic Glades and Barrens.
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Learn MORE HERE about plant adaptations to rocky places.  
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Plants

Click on the plant name to see images.  
​  Plants are listed in order by scientific name.

Trees
Red maple Acer rubrum
Downy serviceberry  Amelanchier arborea
Black birch Betula lenta
Sourwood Oxydendrum arboreum
Rock chestnut oak  Quercus montana
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​Virginia pine Pinus virginiana 
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Shrubs
Fringe-tree Chionanthus virginicus
Mountain sweet-pepperbush Clethra acuminata

Witch-hazel Hamamelis virginiana
Smooth hydrangea Hydrangea arborescens
Ashy hydrangea Hydrangea cinerea
Mountain laurel  Kalmia latifolia 
Catawba rhododendron Rhododendron catawbiense
Great rhododendron  Rhododendron maximum ​
Gorge rhododendron  Rhododendron minus
Winged sumac Rhus copallinum


Vines
Crossvine  Bignonia capreolata
Trumpet vine Campsis radicans
Climbing hydrangea Decumaria barbara
Hairy southern bush-honeysuckle Diervilla rivularis
Carolina jessamine Gelsemium sempervirens

Coral honeysuckle Lonicera sempervirens
Passion flower/May-pop Passiflora incarnata
Virginia creeper Parthenocissus quinquefolia
Greenbrier (whiteleaf/sawbrier) Smilax glauca
Poison ivy Toxicodendron radicans
Muscadine Vitis rotundifolia 

​Ground Layer
Wildflowers
Harebell  
Campanula divaricata
Littleflower alumroot Heuchera parviflora
Rock alumroot Heuchera villosa
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Quaker ladies Houstonia caerulea
Upland dwarf iris  Iris verna
Carolina lily  Lilium michauxii
Partridgeberry Mitchella repens
Hairy spiderwort Tradescantia hirsuticaulis
​Smooth spiderwort Tradescantia ohiensis
Sweet white violet Viola blanda

Grasses
Wavy hairgrass  Avenella flexuosa 
Silky oatgrass  Danthonia sericea
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Poverty oatgrass Danthonia spicata
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Ferns and Fern Allies
Mountain spleenwort Asplenium montanum
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Ebony spleenwort Asplenium platyneuron
Marginal woodfern  Dryopteris marginalis
Myriopteris lanosa Hairy lipfern
Appalachian rockcap fern  Polypodium appalachianum
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Rockcap fern Polypodium virginianum



Representative Trees in order by scientific name

Representative Shrubs in order by scientific name

Representative Vines in order by scientific name

​Representative Wildflowers in order by scientific name

Representative ferns
Picture

​Contents of this site are based on the book The Natural Communities of Georgia, which can be purchased from the University of Georgia Press, Amazon, and other vendors.
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This site is a work in progress: comments and suggestions are welcome.  Email: ​naturalcommsga@gmail.com

  • Home
  • Piedmont
    • Piedmont Overview
    • Mesic (Moist) Forests
    • Oak-Pine-Hickory Forests
    • Bottomland/Floodplain Forest
    • Pine-Oak Woodlands
    • Montane Longleaf
    • Prairies and Savannas (Upland)
    • Wet Meadows and Marshes
    • Granite Outcrops
    • Glades, Barrens, and Woodlands
    • Ultramafic Barrens and Woodlands
    • Cliffs and Bluffs
    • Flatwoods (Upland Depression Swamps)
  • Blue Ridge
    • Blue Ridge Overview
    • Northern Hardwoods
    • Montane Oak Forests
    • Fertile Cove Forests
    • Acidic Cove Forests
    • Oak Forests
    • Pine-Oak Woodlands
    • High Elevation Outcrops
    • Mafic Dome Rock Outcrops
    • Rock Outcrops, Cliffs and Bluffs
    • Ultramafic Barrens and Woodlands
    • Mountain Bogs
    • Seepage Wetlands
    • Spray Cliffs
    • Montane Bottomlands and Flooplains
  • Cumberland Ridge & Valley
    • Cumberland Ridge & Valley Overview
    • Mesic Forests
    • Dry Calcareous Forests
    • Acidic Oak-Pine Forests
    • Pine-Oak Woodlands
    • Montane Longleaf
    • Calcareous (Cedar) Glades
    • Calcareous Cliffs
    • Calcareous Prairies and Barrens
    • Acidic Glades and Barrens
    • Acidic Cliffs and Outcrops
    • Flatwoods
    • Acidic Seepage Wetlands
    • Bottomlands and Flooplains
  • Impact of Rock Type on Plant Composition
  • Plant Adaptations to Deciduous Forests