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Resources < Wildlife Habitats < Guide to Native Plants of Georgia for Wildlife < Symphyotrichum georgianum
Georgia aster is a relict species of post oak savanna/prairie communities that existed in the southeast prior to widespread fire suppression and extirpation of large native grazing animals. Once found in Georgia, Alabama, North and South Carolina and Florida, this pretty, dark purple flower now occurs only in about 60 sparse patches in the first four states. |
By Carol Hassell,
the Call Editor
Georgia is a place of amazing biological diversity, yet much of our wildlife and habitat is threatened or declining as population grows and development or land conversion occurs. The Georgia Department of Natural Resources (DNR), with the help of many caring organizations such as the Georgia Wildlife Federation, developed a strategic plan, known as the State Wildlife Action Plan (SWAP) or Comprehensive Wildlife Conservation Strategy (CWCS), to help ensure we protect wildlife and the habitat it needs to survive.
Among the objectives of the plan is "'keeping common species common' as well as preventing or minimizing further extirpation or extinction of the more imperiled species."
Georgia aster (Symphyotrichum georgianum or Aster georgianus) is such a species. It can exist in a variety of dry, upland habitats, according to a U.S. Fish and Wildlife Service (FWS) 2001 Candidate and Listing Priority Assignment Form. While a member of a very large family of flowers (the Asters or Asteraceae), the decline of this particular species is emblematic of decades of fire suppression. Following is information excerpted from the FWS Assessment and from NatureServe©, (www.natureserve.org) a non-profit conservation organization that provides the scientific information and tools needed to help guide effective conservation action. NatureServe and its network of natural heritage programs are a leading source for information about rare and endangered species and threatened ecosystems.
These widely separated present-day populations of Georgia asters hang in the balance, as well: According to NatureServe, "Remaining populations are adjacent to roads or in utility rights-of-way, or other openings where land management creates conditions similar to those created by natural disturbances. In these locations, the small populations are subject to many threats: invasive species (including kudzu), highway expansion, herbicide application, quarrying,
and development."
In particular, "more utility companies and railroads are shifting to herbicide spraying instead of mowing" for control of vegetation growth, notes the FWS report. This method of removal may have particularly disastrous consequences for the remaining tiny patches of Georgia asters, in part because of the species' reproductive needs. The flowers reportedly are self-sterile; that is, pollen from a single blossom cannot fertilize itself or a flower from a clone -- the same genetic stock. Two flowers from separate stock are required for such reproduction, each pollinating the other. "Long-term survival may be compromised . . . as each small surviving population may represent a single clone (additional stems grow from rhizomes, a sort of underground stem-ed. note)," according to NatureServe.
Large (2" across) heads characterize Georgia aster, featuring dark purple rays (mistakenly called petals) surrounding white disc flowers with purplish tips that darken with age, purplish anthers and whitish pollen. Combined, these features set Georgia aster apart from other asters, including Aster patens (with its light lavender flowers) and Aster grandiflorus (featuring yellow disk flowers instead). Leaves are generally lance shaped and clasp the stem at their bases.
For continued existence, "the primary controlling factor appears to be the availability of light," says the FWS Assessment. "The species is a good competitor with other early successional species, but tends to decline when shaded by woody species. Populations can persist for some undetermined length of time in the shade, but these rarely flower."
Most remaining Georgia aster sites are on private land with a small percentage on U.S. Forest Service and U.S. Army Corps of Engineers land. FWS is working to gain landowner cooperation to protect and manage these sites. The Forest Service has tentatively agreed to conduct prescribed burns on a couple of their sites.
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