The Southeastern US is one of the richest and most biodiverse regions on our planet, the Piedmont Region. Our region has been geologically stable for over 100 million years, and because glaciers never covered our part of the continent, fewer species were lost to the freezing temperatures of the ice age, plus the unusual North-South axis of the Appalachians allowed many species to survive the ice ages and move back south as possible.
Atlanta’s landscape belonged to the Muscogee Creek Nation until 1821, when it was transferred to the US government. American settlement began in our region nearly 200 years after cities like Boston, Philadelphia, and Charleston were founded. Atlanta’s hilly terrain was unsuitable for the large row-‐crop farms more common to Central and South Georgia. Smaller farms, dairy farms and pecan orchards were common in what would become the City of Atlanta, and these were often less destructive to the landscape and soils. Today it’s not uncommon to find trees 150 to 300 years old in Atlanta’s older neighborhoods and greenspaces. Such trees and older landscapes are remnants of the original forest dating back to Muscogee Creek days -‐-‐ not so long ago.
Atlanta’s major urban growth boom did not take place until the 1960s, after air conditioning became widely available and automobiles had become the primary mode of transportation. New highways enabled sprawling growth patterns that skipped over older pockets of forest often found on the steep slopes and narrow stream corridors that were not favored for farming or building. Today these forested areas serve as the ecological backbone of Atlanta’s notable urban forest. Such forests are found in greenspaces and backyards throughout the metro area. Old growth remnant forests can be identified by particular species of trees, by the size and growth form of trees, and by the presence of less common or rare native plants we call “indicator” species. Such species appear only in older soils and many have seed dispersal mechanisms that ensure new plants never sprout very far from the mother plant.
When we find such species in a landscape, we know they’ve been living in the same soils for many hundreds or perhaps thousands of years. Historical records and historic aerial photos can also be used to help locate or identify such areas. In Fulton and DeKalb Counties aerial photographic records date back to the 1930s and 1950s. Mature stands of hardwoods visible in photos from the 1930s were likely established in the mid-‐to-‐late 1800s and sometimes earlier. Original soils are the heart of the forest because they contain the roots and seedbeds of myriad species of native trees and plants, along with the untold thousands of species of fungi and microorganisms needed to support healthy biodiversity. The complexity of soils is barely understood, and many scientists today consider older soils to be a non-‐renewable resource. When such soils remain intact, they can regrow a healthy native forest even after impacts such as timbering. But once those soils are scraped away, there is little hope of recovering our native forest for thousands of years, if ever. While other major cities struggle to replant dead zones and landscapes where little to none of the original ecosystem remains, most metro Atlanta communities have the opportunity to restore woodlands that are still in relatively good condition. The most ecologically intact forests offer the highest return on investments in restoration because, after invasives are removed and controlled, a native forest can sustain itself.